Exam Review Biology

Characteristic of Living Things

  • Growth - grow from inside out 

  • Reproduction - Thing shave limited life span and need to replace themselves

  • Adaptation - adapt to environment in ways favorable to them 

  • Metabolism - Food provide energy and carry out bodily functions

  • Movement - Migration 

  • Irritability - Response to Stimulus; heat, noise, light 

  • Cells - In all living things 

Species 

  • Organisms able to interbreed in nature and create fertile offsprings

Species Concept 

  • Morphological 

    • Morphology (Shape, size, description)

    • Advantage: Simple

    • Disadvantage: Difference between two organisms is enough to separate them

  • Biological

    • Organism ability to interbreed and produce fertile offspring in nature

    • Advantage: Used Widely

    • Disadvantage: Can’t be applied in all situations 

  • Phylogenetic 

    • Evolutionary relationship between organisms 

    • Advantage: Can be applied to extinct species

    • Disadvantage: Phylogenetic of all animal unknown 

Linnaean System of Classification

  • Aristotle compulsion identify and catalog organisms 

    • Responsible first written account of a classification system

    • Identifies 1000 species

  • Universally accepted and widely used is Linnaean System of Classification

  • Carolus Linnaeus - Father of Taxonomy 

  • Taxonomy - identified and naming species based on morphology




Binomial Nomenclature 

  • Means using two words in the name Ex. Homo sapiens 

    • Genus: Written before species Capitalized and Italicized

    • Species: Written after Genus Lower case Always italicized

Taxonomic Classification

  • Organized from most general to most specific (Genus and Species 2 of 8 Taxonomy)

  • There are also other ranks within these Ex. Suborder, Infraclasses, Subspecies, etc.

Common Ancestors 

  • Two species share much same evolutionary history, means they fairly recent common ancestor

  • Ancestor: Organism from which other group organism are descended 

Anatomical Evidence of Relationship

  • Anatomy: Study of structure and form, including internal system of organisms

    • Ex. Evolutionary relation between modern bird and dinosaurs

    • SImilarity between dinosaurs and birds are bone structures

      • Same bones found in 4 mammals matching bones (Homology)

      • SIze proportions of the bones have been modified for different uses



Physiology Evidence and Relationship

  • Physiology: Study of physical and chemical function of organisms (How They Work) (Including internal Process) 

  • Scientist study biochemistry organism compare structures such as parts of cell, tissue, and proteins

  • Ex. Guinea pig and mice once consider closely related but several proteins show significant differences leading to reclassification of guinea pigs 



DNA Evidence of Relationship 

  • Advances in DNA allow comparison between sequences 

  • Higher similarities between sequence suggest recent common ancestry

  • Ex. DNA shows fungi closer related to animals than plants 

Phylogenetic Tree

  • Branching diagram use show evolutionary relationship among species

  • Phylogeny is evolutionary history of species 



Importance of Classification 

  • Source of Pharmaceutical drugs form species known produce viable proteins or chemicals

  • Tracing transmission disease through species share certain genetic characteristics

  • Increasing crop yield and disease resistance in plants by having knowledge of different taxa and their characteristics 

  • Finding new species to reclassify an organism as a separate species 

Classification

  • 2 Types of classification

    • Un-nested - No hierarchy all groupings equal 

      • Ex. Fruits (Bananas, Apples, Lemons)

    • Nested - Hierarchy Exist

      • Ex. School (Principal, VP, Teachers, Students)

  • Taxonomic grouping nested (Belong in Hierarchy)



Species Classification

  • Species assigned a classification by placing eight nested categories (Ranks)

  • Taxa name of group which Linnaeus assigned organisms 

    • Domain →  Dear 

    • Kingdom → Kings 

    • Phylum → Played 

    • Class → Chess 

    • Order → On 

    • Family → Fine 

    • Genus → Green 

    • Species → Sand 

Taxonomy 

  • Linnaeus place organisms into taxa based on morphology (Similar structure and function)

  • Each level or taxon groups together organisms share more characteristics than the level above

  • Most Generic Grouping: Domain

  • Most Specific Grouping: Species 

The Six Kingdoms

Cell Types Kingdoms, and Domains

  • Prokaryotic

    • Cells Less Complex 

    • No Nucleus

    • No Membrane

    • Bound Organelles

    • Single circular chromosomes (DNA)

      • Archaea

      • Bacteria

  • Eukaryotic

    • Cells are more complex 

    • Cells contain a nucleus

    • Cells contain membrane bound organelles

    • Can be multiple, linear chromosomes (DNA)

      • Protista

      • Fungi

      • Plantae

      • Animalia



Eukaryotic vs. Prokaryotic Cells

  • Difference between Archaea and Bacteria so vast that scientist use Domains rank more general than

  • Kingdom, classify them 

    • Ex. Apple tree and blue whale have more in common than bacteria and archaea

Common Taxon Types

  • Common Animalia

    • Insects, fish, snakes, birds, dogs, bears, humans, lizards, frogs

  • Common Phylum

    • Chordata: (Central Nervous System) Ex. Lizards

    • Arthropoda: (Jointed appendages) Ex. Lobster, Centipedes

    • Echinodermata (Spiky Skin) Ex. Starfish, Urchins

    • Mollusca (Soft Body) Ex. Snails, Octopus

    • Cnidaria (Venomous cells that help transmit info) Ex. Jellyfish 

Classifications

  • Heterotrophs

    • Consumers

  • Autotroph

    • Produces

Human Taxonomy 

  • Domain: Eukarya 

  • Kingdom: Animalia 

  • Phylum: Chordata 

  • Class: Mammalia 

  • Order: Primates 

  • Family: Hominidae 

  • Genus: Homo 

  • Species: sapiens 

Dichotomous Key

  • Tool used classify organisms (Using Morphology)

  • Many two part choices identify species 

    • Spider Keys

    • Number Keys

Genetic Diversity

  • Variety of Genes (Heritable characteristics) in a population

Species Diversity 

  • Refers to variety abundance of species in a given area

  • Species Richness - Many different types species in an area

Ecosystem Diversity

  • Variety of ecosystem in the biosphere

  • Biosphere region on planets that support life 

Ecosystem Services 

  • Ecosystem Services - Benefits provided by organisms in sustainable ecosystems



Viruses

  • 2 types of cells 

  • Prokaryotes

    • Circular DNA, single chromosome 

    • Not divide by mitosis or meiosis

    • Asexual reproduction 

    • Unicellular 

    • Membrane-bound organelle absent Anaerobic respiration (do not require oxygen)

  • Eukaryotes

    • DNA in a membrane-bound nucleus, several chromosomes

    • Divide Mitosis and Meiosis 

    • Sexual Reproduction

    • Most are Multicellular Membrane-bound organelles

    • Most undergo a aerobic respiration (Require Oxygen)



Viruses not fulfill all criteria for life but do not meet some of criteria

  • Evidence that viruses are non-living:

    • Do not grow or carry out respiration 

    • Only contain one kind of nucleic acid; RNA or DNA

    • Contain only a few enzymes, No cellular organization

  • Evidence that viruses are living 

    • Contain on nucleic acid 

    • They can replicate (But require a living cell)

    • They can evolve



Viral Nomenclature

  • They named for the disease they cause 

    • Ex. Rabies virus, polio virus or for the tissue they infect

    • Ex. Adenovirus (Attacks adenoid tissue)




Viral Characteristics

  • Core Nucleic Acid

    • Set of genetic instruction with DNA or RNA Single or Double stranded

  • Capsid

    • Protein COat - Surrounds nucleic acid to protect it 

    • Lipid Membrane - Only in some, Viruses if present envelopes, Virus if absent naked, Virus Surround protein coat 

  • Shape

    • Determined by the protein in coats 

    • Play role in infection process 

      • Ex. Helical, Spherical and Icosahedral (20 Sided)

Viral Structure 

  • Bacteriophage 

    • Virus that infect bacteria and is a Distinct head and tail region 

Viral Reproduction 

  • Viruses don’t carry chemical machinery needed carry out chemical reaction of life

  • Only carry one or two enzymes required to de-code genetic material 

  • Virus must have Host Cell in which to live and make more viruses 

Host Cell

  • Can be animal plant or bacteria 

  • Viruses selective - host specific 

  • Host Range - number of host species, tissue or cells a virus can infect

  • Broad Host Range - Rabies (Infect human, dogs, racoons)

  • Narrow Host Range - Cold Virus (Infects upper respiratory tract in humans)

Viral Infection - Lytic Cycle 

  • Attachment and Entrance

    • Virus particle attach to host cell

    • Viral Specificity - Viral protein coat must match receptor site on host cell

    • Particle releases its genetic instructions into the host cell

  • Synthesis

    • Injected genetic material recruits host cell’s enzymes to replicate it’s viral components

  • Assembly

    • Viral Components (Nucleic acids, Enzymes, Proteins) assembled into new virus particles

  • Release

    • New virus particles released from host cell

    • Two methods of release

      • Lysis - Virus particles break host cell open and destroy it

      • Budding - Virus particles pinch out from the host cell membrane (Enveloped Viruses)

Viral Infection - Lysogenic Cycle 

  • Viruses do not reproduce right away, called Cycle retrovirus 

  • Co exists with host cells integrating own nucleic acid with host cell DNA 

  • Virus contain enzyme (Reverse transcriptase) copies viral RNA into DNA 

  • When host cell reproduce viral genetic instruction copied into host cell’s offspring

  • Virus remains “dormant” until triggered takes over host cell via Lytic Cycle

    • Ex. HIV 

Summary of two Infections

  • Lytic Cycle 

    • Virus Replicates and Burst from Cell 

  • Lysogenic Cycle 

    • Viral Nucleic DNA merges with host cell DNA and replicates through host cell reproduction 

Viruses and Human Health 

  • Destruction host cell causes symptoms of disease

  • Virus are not destroyed by Antibiotics

  • Vaccines inactive forms virus that injected so the body can produce antibodies they allow for body to become immune to the disease

Immunization

  • Active immunity when body manufactures antibodies combat diseases

  • Lymph nodes store the memory of antibody so that it can produce again if needed

  • Immunity is life long and was created under natural circumstances

Passive Immunity

  • Temporary antibodies transferred to person from another person or animal

  • Antibodies transferred from mother to her fetus through the placenta so that the fetus will be immune to the same viruses as mother for a short time. This is why babies need vaccination when they are a few months old 

    • Ex. Tetanus shot contains antibodies from horses exposed to tetanus toxin. Thus antibody production can be stimulated. Tetanus shots are taken every 10 years

Archaea

  • Three major type of Archaea 

    • Methanogens

    • Halophiles

    • Thermophiles

Methanogens 

  • Methane producing 

  • Live below surfaces in swamps, bogs, marshes and sewage treatment plants

  • Use Co2, N2, or HS for Energy

  • Expel CH4 as a waste product 

Halophiles

  • Salt loving Archaea, Live in salt pools evaporation ponds etc.

  • Live in salt concentration 20% or greater 

Thermophiles

  • Extreme heat environments, live in hot sulfur springs and use sulfur for energy 

  • Some live near volcanoes and Grow best at 80 degrees celsius + Temperatures

Bacteria 

  • Many can perform Photosynthesis

  • Cell Walls made of Peptidoglycan (Archaea lack peptidoglycan)

Gram Staining 

  • Staining technique used identify bacteria 

    • Gram Positive - Thick peptidoglycan wall 

      • Retain crystal violet Gram Stain 

    • Gram Negative - Thin Peptidoglycan Wall 

      • Crystal Violet stain washes out, counterstained red/pink

Morphology 

  • Bacteria and Archaea often classified according to morphology

  • 3 Basic SHapes

    • Coccues (Pl. Cocci) Spherical Bacteria

    • Bacillus (Pl. Bacilli) Rod Shaped Bacteria 

    • Spirillim (Pl. Spirilli) Spiral Shaped Bacteria 




Morphology

  • Prefixes added to the shape name to indicate arrangements 

    • Mono - Single 

    • Diplo - Pairs

    • Strepto - Chains

    • Staphylo - Clumps 

Aggregations: Cells grouped Together 

  • Some individuals prokaryotic cells (bacteria or archaea) group together

    • Streptococcus - Bacteria found in chains of spheres

    • Streptobacillus bacteria are rod shaped and found in chains 

Comparing Nutrition 

  • Archaea 

    • Process of methanogenesis obtains nutrients. Methanogenesis is anaerobic process that occurs in environment lack oxygen Some Archaea use sunlight as a source of metabolic energy but no reliable evidence of Photosynthesis

  • Bacteria 

    • Some are Photosynthetic 

      • Ex. Cyanobacteria use solar energy to convert carbon dioxide and water into sugar and oxygen.

Comparing Habitats

  • Archaea and Bacteria occupy environment with oxygen (Aerobic) and without oxygen (Anaerobic)

  • Archaea

    • Ability to live in extreme environments called extremophiles

  • Bacteria 

    • Organisms that occupy an environment with moderate (Less extreme) conditions called Mesophiles. There are few extremophilic Bacteria  

Reproduction - Binary Fission

  • Prokaryotes reproduce through asexual process of binary fission producing two genetically identical cells



Conjugation 

  • There is transfer of genetic material (DNA) Involving two cells (Prokaryotes)



Endospores

  • Protecting Genetic Material 

    • Endospores

      • Dormant bacterial Cells (Not seen in Archaea)

      • ABle to survive for long periods during extreme conditions

    • Ex. freezing high temps, radiation and toxic chemicals 



Bacteria and Human Health 

  • A) Clostridium botulinum is an anaerobic bacterium that can cause illness in humans (food poisoning)

  • B) Streptococcus pygones is a Gram-positive bacterium that causes strep throat infections

  • C) Streptococcus mutans is a Gram positive bacterium that causes tooth decay





Bacteria and Human Health 

  • Most bacteria are harmless, or beneficial, Trillions of bacteria live in your gut: (symbiosis) 

    • Help the immune system 

    • Provide vitamins 

    • Prevent growth of pathogenic bacteria 

    • Some prevent tumor growth

Protists: General Characteristics 

  • Cells are eukaryotic 

  • Most are unicellular

  • Most are aquatic, or wet environment organisms 

  • Most have aerobic metabolisms (use O2)

  • Reproduce Asecually (Many can reproduce sexually as well) 

Classification

  • Three Main classes of Protists 


Animal Like 

Plant Like 

Fungi Like 

Amoebas, ciliates, flagellates 



Consume other organisms for food some parasites 

Diatoms, euglenoids, dinoflagellates



Make their own food by photosynthesis some consume other organisms when there is no light, others are symbionts 

Slime Moulds



Absorb nutrients from other organisms, living or dead 

Some consume other organisms, some are parasites 

Animal Like Protists

  • Also called protozoans 

  • Proto (first) zoa (animals)

  • They are heterotrophs

  • Some are parasites - live in or on another organism causing harm

  • 4 Main Phyla of Protozoa

    •  Flagellates - phylum zoomastingina 

    • Cercozoans - Phylum cercozoa 

    • CIliates - Phylum ciliophora

    • Sporozoans - Phylum sporozoa 



Cercozoa 

  • No cell Wall 

  • Change shape 

  • Use pseudopods for locomotion 

  • Ex. Amoeba 



Ciliophora

  • No cell wall 

  • Use cilia for locomotion



Amoeba 

  • An Amoeba Feeds on small organisms 

    • As an amoeba approaches food, pseudopodia form and eventually surround the food 

    • The food becomes enclosed in a food vacuole

    • Digestive enzymes break down the food, and the nutrients diffuse into the cytoplasm

    •  



Paramecium




More Protozoa

  • Zoomastigina 

    • No cell wall 

    • Use a flagellum to move around 

    • Ex. Trichonympha (a mutualistic protists in termites)

  • Sporozoa 

    • No cell wall 

    • No independent means of locomotion 

    • Entirely parasitic 

    • Reproduce sexually and asexually 

    • Eg. Plasmodium vivax (P. vivax causes malaria)

  •  



Human Health 

  • Malaria is caused by the protist Plasmodium vivax, and others (a sporozoan)  

  • Plasmodium has a complex life cycle

Malaria 

  • High fevers, shaking chills, and flu-like illness which is 300-500 million cases per year 

  • 1 million + deaths (a leading cause of death worldwide)



Fungus-like Protists 

  • Heterotrophs that absorb nutrients from living organisms, dead organisms and waste matter 

  • Like fungi, they produce spores (reproductive cells) 

  • Differ from fungi in the material that makes up the cell wall 

  • 3 main types: plasmodial slime moulds, cellular slime moulds and water moulds



Plant - like Protists

  • Contain pigments in chloroplasts to carry out photosynthesis 

  • Usually contain chlorophyll making them green in color 

  • 3 main divisions:



1. Diatoms: Phylum Chrysophyta 

  • Phytoplankton 

  • Unicellular, free floating aquatic organisms 

  • Walls are 2 parts, one smaller than the other, smaller fits inside the larger 

  • Mostly reproduce asexually by mitosis 

  • Can reproduce sexually when environmental conditions are unfavourable



2. Dinoflagellates: Phylum Pyrrophyta 

  • Also phytoplankton 

  • Have 2 flagella at right angles to each other 

  • Under ideal conditions they are able to reproduce very quickly, resulting in an algal bloom 

  • Some have a red photosynthetic pigment, creating red tides



3. Euglenoids 

  • Most found in shallow, fresh water 

  • Undergo photosynthesis, but also have flagella and can absorb nutrients 

  • Tend to be autotrophs in the sunlight and heterotrophs in the dark 

  • Most common is the Euglena’

Fungi 

  • Eukaryotic Organisms , Heterotrophic and contains the polysaccharide chitin in their cell walls

  • Were once considered part of the plant kingdom Evolved close to 900 million years ago



Classification of Fungi 

  • Some Phyla INclude 

    • Zygomycota - Moulds (Breads, Dungs Moulds)

    • BAsidiomycota - Mushroom (Cap Fungi)

    • Ascomycota - Yeast, morrells, truffles

Fungi vs. Plants

  • Similarities 

    • Eukaryotic, cell walls anchored in soil or substrate Reproduce asexually, sexually or both; Stationary 

  • Difference 

Plants

Fungi 

One nucleus per cell

Multiple nuclei 

Autotroph

Heterotrophs

Starch for energy storage 

Little or no energy storage 

Have Roots

No roots

Cellulose in cell walls

Chitin in Cell walls

Some Reproduce by seeds

None reproduce by Seed




Fungi Nutrition

  • Feed by extracellular digestion 

  • As hyphae grow across its substrate, digestive enzymes are released 

  • Macromolecules are broken down into smaller molecules and then absorbed into the hyphae

Nutrition

  • Parastatic - Absorb nutrients from living cells of hosts (Ex. Cordyceps Fungi. For Ants)

  • Predatory - Soil Fungi trap prey with mycelium 

  • Mutualistic - Partnership with other organisms (Mycorrhizae)

  • Saprobial - Feed on dead organisms or waste decomposers 



Reproduction 

  • Asexual Reproduction 

    • Fragmentation - (Piece of Mycelium breaks off and form a new individual)

    • Budding - (Seen in yeast, parents cell does Mitosis creates daughter cell)

  • Sexual Reproduction

    • Spore Production - (Spores are Haploid) (Half the amount of DNA)

    • Spores fuse nuclei to form a diploid cell 

Symbiosis 

  • Trees have fungi living close quarter to roots

  • Fungus helps plant absorb water and nutrients

  • FUngus benefits by absorbing sugar and amino acids from the plants 

  • Relationship is called mycorrhizae

Candida Albicans Fungus

  • Cells of the Yeast - like fungus is a cause of yeast infections (Candidiasis)

Dermatophyten

  • This cause athlete foot and scalp ringworm 



The Shift to Land

  • It is hypothesized that green algae closest evolutionary relatives of land plants based on several structures

    • Chlorophyll

    • Cellulose Cell Walls

    • Store Food Energy as Starch 

    • DNA ANalysis show similarities 



Adaptation to Life on Land 

  • Plant Embryos 

    • Reproduce embryos, small, simple, multicellular plants that are dependent on parent plant for a time

  • Vascular Tissue 

    • 1st land plants were small simple eventually developed tissue to transport material over long distance 

    • Vascular Tissue Contains:

      • Xylem (Carries Mineral and H20)

      • Phloem (Transport Sugars)

  • Roots

    • Vascular tissue allowed evolution of roots with string anchoring ability to land 

    • Cells specialized in absorbing and transporting water and nutrients 

  • Leaves 

    • Increased the surface area of the plant above ground and Improving Photosynthesis

Non Vascular Plants: Bryophytes 

  • 3 Phyla: Mosses, Liverworts and Hornworts

  • No Vascular tissue, rely on diffusion and osmosis move nutrients

  • Hold large quantity of water 

  • In ecosystem role to recycle nutrients

  • Potential sources of pharmaceuticals 



Seedless Vascular Plants

  • 4 Phyla: Whisk fern, club mosses, horsetail and ferns 

  • Vascular tissue enabled plants to grow tall 

  • Ferns are the most diverse 

  • Ferns are found on the floors of temperate forest through Canada

Seed-producing Vascular Plants 

  • Seeds allow plants to reproduce sexually without needing water and provides protection against harsh environment conditions 

  • Two groups: 

    • Gymnosperms 

    • Angiosperms

Gymnosperm Diversity 

  • Seeds are exposed on surface of cone scales 

  • Gymnosperm means ‘naked seed’ 

  • In cool boreal & alpine ecosystems of Canada 

  • Most are evergreens  photosynthesis when conditions are suitable 

    • Examples: conifers such as pines, spruce, cedars

Angiosperm 

  • Flowering plants 

  • Seeds are contained in a fruit 

  • Extensive diversity 

  • Divided based on seed structure: 1) monocots, 2) dicots 

    • Examples: non-coniferous such as oaks, maples, grasses and weeds

Diagram

  • Plants

    • Nonvascular and Vascular

      • Vascular - Seedless and Seed Producing 

        • Seed Producing - Gymnosperms and Angiosperms

          • Angiosperms - Monocots and Dicots 

Characteristics of Animals 

  • Use Oxygen, Heterotrophs, All reproduce, All Move, All Grow, Instincts, Eukaryotic, Multicellular 

Animal Kingdom

  • Cells: Eukaryotic, multicellular, lack cell walls 

  • Locomotion: Most are motile in at least one part of their lives (contrast with sessile plants/fungi) 

  • Nutrition: heterotrophs 

  • Reproduction: Mostly sexual, produce embryos




Characteristics used to Classify 

  • Body Layers

    • All Animilia have 3 (except sponges)

      • Ectoderm, Mesoderm, Endoderm

  • Body Symmetry 

    • Radial - can be divided on any plane Bilateral - divided into two mirrors

  • Body Cavities

    • Presence, absence of a body cavity (coelom) filled with fluid to keep organs in place 

  • Segmentation 

    • The division of the body into repeated segments

  • Body Organization 

    • Some animals lack tissues (sponges) but most have tissues

  • Movement 

    • Most are motile (can move), some sessile (don’t move) as adults (sponges).

Observance and Inference 

  • Observe 

    • Made with 5 Senses

  • Infer 

    • Conclusion and Deduction made from observation

Animal Invertebrates

  • Phylum Mollusca

    • Bilateral symmetry, 3 layers of cells, a coelom, soft body (Sometime Shells)

    • Bivalves (Clams, mussels), Gastropods (Snails) and Cephalopods (Squids and Octopus)

  • Phylum Cnidaria 

    • Have Tissue (Nerve and Muscle), mobile, sting their prey 

    • Exhibit radial symmetry 

    • Hydras, Jellyfish, Corals, Sea Anemones

  • Phylum Echinodermata 

    • Bilateral symmetry, tube feet that end in “suction cups”, spiny endoskeeton 

      • Feed by forcing water ibto the tube feet 

      • Sea Stars, Sea Urchins, Sea Cucumbers

  • Phylum Arthropoda

    • Largest animal pHylum

    • Have legs mad for moveable section, body divided into segments, hard exoskeleton (Outer Protection)

    • Spiders, Scorpions, Crustaceans, Insects 



Vertebrate Animals 

  • Phylum Chordata 

  • Five major classes: 

    • Fish 

    • Amphibians 

    • Reptiles 

    • Birds 

    • Mammals 

  • Fossil Order

    • Fish 

    • Amphibian

    • Reptiles

    • Birds 

    • Mammals 

Fish 

  • Jawless Fish 

    • Cartilage skeleton, No Jaws, Gills, No appendages, Marine and Freshwater

  • Cartilaginous Fish 

    • Cartilage Skeleton, Have jaws, vertebrate, Gills, Paired Appendages, Internal Fertilization, Mostly Marine 

  • Bony Fish 

    • Bony skeletons, Jaws, vertebrae, Swim bladder, External fertilization, Marine and fresh

Amphibians

  • First appeared 360 Mya, Fins Bony fish evolved into limbs

  • Tetrapods (2 pairs of limbs) (As are other classes - Reptile/Birds/Mammals)

  • Gas Exchange via lungs and moist skin Spending a portion of their life cycle on land

Reptiles 

  • Appeared 300 Mya 

  • 3 Extant order

    • Squamata - Snakes and lizards 

    • Testudines - turtles 

    • Crocodilia - crocodilians 

  • Body scales create waterproof barrier, with lungs for respiration nd shelled eggs

Birds

  • Appeared 150 Mya, Related to Dinosaurs

  • Reptiles ectothermic, birds endothermic 

  • Lightweight feather, hollow bones 

Mammals

  • Appeared 120 Mya

  • Mammals nurse their young (mammary)

  • Mammal groups:

    • Monotremes – egg laying mammals 

    • Marsupials – pouched animals 

    • Placentals – placenta

Biodiversity 

  • Variety of species, genes and ecosystems 

Mass Extinction

  • Large scale dying out of large percentage of living organism 

  • Geological history shows there have been 5 mass extinction events

  • Some experts argue that we are in midst of our 6th mass extinction

























Unit 2 

Cell Cycle 

  • Somatic cell (Cell rather than reproductive cell) lives existence of three separate stages

    • Interphase (Longest Stage)

    • Mitosis

    • Cytokinesis (Quickest stage)

    • Interphase - 

      • G1 - Cell Content duplicate 46 chromosomes 

      • S - DNA Replication 92 chromosomes 

      • G2 - Check for mistake or any repairs 92 Chromosomes

Interphase

  • Time between cell division and, includes process of DNA replication in preparation for cell division

  • Period of growth development and regular day to day maintenance

  • DNA exist as chromatin (Uncondensed)

Prophase

  • DNA cell begins condense into chromosomes, includes nuclear membrane dissolves 

  • Centrioles with spindle fibers migrate to either pole of cell

  • Nucleolus disappears nuclear membrane breaks down 

Metaphase 

  • Spindle fiber attachment to the centromere of each chromosome and line them up at the equatorial plate 



Anaphase 

  • Centromere splits, spindle fibers separate each chromosome

  • Spindle fiber shorten and pull chromosomes to opposite poles of the cell 

Telophase 

  • Chromosome unwind back into chromatin

  • Nuclear membrane and nucleus reform 

Cytokinesis 

  • Division of the cytoplasm 

  • Animal Cell: cell membrane pinches

  • Plant cell: Plate from between to cells 

  • Cytokinesis end with two separate daughter cells that are genetically identical 



DNA Structure

  • DNA consist 2 molecules are arranged into a ladder like structure called double helix 

  • MOlecule of DNA made up of million of tiny subunits called nucleotides,

  • Each nucleotide consists of:

    • 1. Phosphate Group

    • 2. Pentose Sugar (DNA: Deoxyribose, RNA: Ribose)

    • 3. Nitrogenous BAse (DNA: ATCG, RNA: AUCG)

Nucleotide Structure 



Pentose Sugar 

  • 5 Carbons Sugars 

    • RNA - Ribose 

    • DNA - Deoxyribose

  • Difference is the hydroxyl group on #2 carbon

Backbone

  • Sugars and Phospahte form backbone of DNA molecule, whereas the bases form the “rungs”



The 4 (5) Nitrogenous Bases 



Complementary Base Pairing 

  • A always bonds with T

  • C always bonds with G

  • Order of bases in one strand determine order in the other 

  • RNA has diff sugar does not contain thymine but has another base called Uracil (U) in RNA A pairs with U

  • In general purines do not pair with purines and pyrimidines do not pair with pyrimidines because: 

  • purines are too big to fit into the helix. 

  • pyrimidines are too far from each other to form hydrogen bonds



Genome 

  • The complete sequence (order that the bases appear) of DNA is called the organism’s genome

  • Also, DNA is Antiparallel! One strand will run 5’ to 3’ The opposing strand will run 3’ to 5’








Copying DNA 

  • DNA replicated the double helix unwinds and each strand serves template for new strand 

  • New strand built on original strand using free nucleotides by complementary base pairs 

  • Replication complete 2 identical strands DNA each double stranded 

  • Method of replication refer semi conservative model because new DNA molecule half original DNA 



Chromosomes Parts



Karyotype 

  • Photographs of pairs of Chromosomes

  • Can be used to diagnose some diseases 



Chromosome 

  • Homologous chromosomes – same sequence of genes 

  • Allele – Different form of same gene 

  • Autosomal – Non sex chromosome (1-22) 

  • Sex – X or Y chromosomes (XX – female, XY –   male)




Reproduction

  • Haploid Cells - Half DNA count, represented by n 

  • Diploid cells - Full DNA count, represented by 2n 







Gametes 

  • Haploid gametes keep chromosome number from doublon in each succeeding generation

  • Haploid gametes produce special sort cell division called meiosis

  • Meiosis - occurs only in reproductive organs, ovaries and testes 

  • Purpose of meiosis produce sperm and egg

    • Spermatogenese - Sperm Production 

    • Oogenesis - Egg cell Production

Summary Meiosis 

  • Involves 2 cell Divisions, and produces 4 cells from 1 parental cell 

  • Each of the daughter cells has 23 individual chromosome rather than 23 pairs 

  • Meiosis reduces the chromosome number from diploid to haploid

  • Meiosis preceded by chromosome duplication

    • Meiosis the cell divides twice to form four daughter cells



Meiosis 1

Prophase 1 

  • Chromatin condense into Chromosomes

  • Each double chromosome lines up next to homologous chromosomes

  • Lining  up process called synopsis

  • When they come together and 4 chromosomes come together called Tetrad

  • Crossover, thye trade sections of dna 

Metaphase 1 

  • Homologous chromosomes line up 

  • Nuclear membrane gone spindle fibers  

  • There invat called independent assortment

Anaphase 1 

  • Chromosomes pulled opposite sides (No centromere split pulling are full chromosomes

Telophase 1

  • Nuclear membrane form 

  • Chromosomes unwind into chromatin 

  • Cytokinesis is going to happen between telophase 1 and prophase 2 

  • Also called interkinesis

Prophase 2 

  • The chromosomes condense and the nuclear envelope breaks down. 

  • Centrosomes move to poles of cell and spindle fibers form between them 

Metaphase 2

  • Chromosomes line up along the metaphase plate 

  • Spindle fiber each side of cell capture sister chromatid on either side of metaphase plate

Anaphase 2

  • Sister chromatids pulled apart to opposite poles of cells 

Telophase 2

  • Nuclear membrane reforms around each set of chromosomes and the chromosomes unravel

  • Ring proteins called contractile ring forms around equator of the cell

  • Ring shrinks pinching membrane inward creating cleavage furrow

  • Four haploid cells and telophase occur at same time 

  • Female - Ovum (Larger Egg Cell) Polar Bodies, Mature egg cell (Only embryo fertilize)

  • Male - Spermatids (All same Size) Mature Sperm Cell



Genetic Variation in Meiosis 

  • Meiosis provides for a vast amount of genetic variation because of:

    • Crossing over

    • Independent assortment

    • Additional genetic variation is achieved through mating of non-related individuals 

Crossing Over 



Independent Assortment

  • In metaphase 1, chromosomes assort themselves independently of other pairs 

  • The number of genetically distinct gametes produced from a diploid cell is 2n

  • N = the number of chromosomes pairs 

    • 2^23 = 8,388,608 combinations 

Errors in Meiosis 

  • 2 types of chromosomes errors can occur in Meiosis: 

    • Change in chromosomes structures, change in chromosome number (Extra chromosome or a missing chromosome)

    • Mutation: A permanent change in genetic material of organisms

Errors in Chromosomes Structures

  • Deletion – portion of chromosome deleted 

  • Inversion – section of chromosome flipped 

  • Duplication – section of chromosome is duplicated 

  • Translocation – section of one chromosome attaches to a different chromosome



Errors in Chromosome Numbers

  • Nondisjunction occurs when either 

    • Homologous fail separate during anaphase 1 of meiosis 

    • Sister chromatids fail separate during anaphase 2

  • Trisomy - One extra chromosome (2n + 1)

  • Monosomy - one missing chromosome (2n - 1)

  • Sex chromosome nondisjunction (extra X or Y or lacking Y)

Errors and Defects  

  • Trisomy 21 is down syndrome

  • Trisomy 13 is patau syndrome  

  • Trisomy 18 is Edward’s syndrome

  • XXY is Klinefelter syndrome 

  • YYX is Jacob syndrome 

  • XXX is Trisomy X 

  • Monosomy X is Turner’s Syndrome



Gametogenesis

  • 2 haploid gametes unite form diploid zygote 

  • Undergoes mitosis form many diploid cells develop into a multicellular body 

  • THese diploid cell specialize and become gamete producing cells

  • Gametogenesis - formation of sex cell during meiosis 

  • Producing cell undergo meiosis form haploid cells, bringing life cycle full

Spermatogenesis

  • Happen in Testes , begins with diploid spermatocyte and undergoes many mitotic division before meiosis 

  • Produce 1 billion sperm cells daily

  • Cytoplasmic division equal after meiosis 1, 4 sperm cells produces

  • Sperm lose cytoplasm and streamline to form a head and a tail for locomotion

  • Purpose: Produce many viable sperm to increase chance of fertilization

Oogenesis 

  • In Ovaries begins with diploid oocyte becomes dormant in prophase 1 until puberty 

  • One ootid (egg cell) produced a month

  • Cytoplasmic division unequal after meiosis 1 

  • 1 out of 2 daughter cell receive cytoplasm polar bodies which die and absorbed by body 

  • Purpose: ensure ovum (Egg cell) has enough nutrients to support the developing zygote 





Genetics 

  • Study which examines the inheritance of Biological traits 

What did Mendel do 

  • Austrian Monk examined passing of traits from parents to offspring (heredity) during mid (1850’s), Studies botany mathematics

Mendel's Pea Plant

  • Experimented 3 main reasons 

    • Only express two traits  (Ex. green or yellow seeds)

    • Self cross pollinate (good for comparison)

    • Grow quickly and readily available

Mendel’s Crosses

  • Crossed a true breeding yellow pea with true breeding green pea (Meaning that those peas have only ever expressed that color of pea)

  • Cross - Fertilization of specific female gamete with a specific male gamete 



F1 Cross



Cross Result 

  • The Cross Result is the fact of that the Ratio is 

    • 3:1





Mendel's Experiment 

  • It was thought traits would create blends

    • Ex. Round seed crossed with wrinkled seed = Slightly wrinkled 

  • Mendel proved not to be the case, crossing round seeds with wrinkle seeds, always producing round seeds. Therefore, round - Dominant 

  • Trait dominated over/masked the other in all experiments

  • Symbols represent dominant recessive traits 

    • Capital Letter = Dominant trait (R)

    • Lowercase Letter = Recessive Trait r

Mendel's Conclusion 

  • Parent contributes one allele (trait) Each out of two alleles for a gene 

    • If two alleles are the same = Homozygous 

    • If two alleles are different - heterozygous (Carrier)

  • Law of Segregation -  Alleles seperate/segregate during sex cell formation 



Genetic Terminology 

  • Characteristic/Trait - observations of an organism’s appearance. There are two alleles for each trait (maternal and paternal).’

  • Homozygous - purebred, an organism that carries two identical genes for a trait.

  • Heterozygous -  hybrid, an organism that carries two different genes for a trait.

  • Monohybrid cross - the crossing or inheritance of ONE trait.

  • FIlial Generation - the generation of the offspring being studied (F1 = 1st generation, F2 = 2nd generation).

  • Dominant - the trait that is expressed when an individual is heterozygous.

  • Recessive - traits that are only expressed when an individual is in a homozygous state.

  • Carrier - an individual who carries a recessive gene along with its dominant allele (heterozygous), dominant gene is expressed.

  • Genotype - refers to the combinations of genes carried by an individual.

  • Phenotype - a physical description of the traits an organism expresses

  • Punnett Square - a method for predicting the possible offspring when two organisms are crossed (bred or mated).

Mendel's Monohybrid Crosses 

  • Monohybrid cross crosses is crossing/inheritance of One trait. Ex. Plant height trait only

  • Punnett Square a method determining genetic probability of offspring’s genotypes and phenotypes 2 parents organisms are crossed (Bred or Mated)

  • Record the probability of each genotype and its genetic description.  

  • Record the probability of each phenotype and its phenotypic description



Test Cross 

  • Can be performed to determine if an individual is homozygous or heterozygous for a dominant phenotype. 

  • The unknown parent is crossed with a homozygous recessive individual. 

  • Analyzing the offspring can provide insight into the unknown parent.



 Exceptions to Mendel’s Law 

  • Mendel’s inheritance pattern (dominant and recessive inherited traits) does not apply to all organisms. 

  • There are 3 exceptions: 

    • Incomplete Dominance 

    • Codominance 

    • Multiple Alleles



Incomplete Dominance

  • A third (new) phenotype appears in the heterozygous condition because neither allele can conceal the presence of the other 

  • Flower Colour in 4 O’clocks (Mirabilis jalapa) 

  • Superscripts can be used to illustrate the alleles for colour 



  • If the white and red flower are crossed, all offspring in the F1 generation will be pink.

  • Ex.






Codominance 

  • Occurs when both traits express at same time 

  • Ex. shorthorn cattle, roan calves have intermingled red and white hair

  • In Heterozygous condition, allele are expressed equally 

    • Ex. Sickle cell Anemia in HUmans 

Multiple Alleles 

  • Two possible alleles: dominant allele controlled the trait.

  • It is possible to have more than two different alleles for one gene.

Blood Type is an EX of a Common Multiple Allele Trait 

  • There are 3 different allele for blood type (A,B and O)

  • Blood alleles: IA , IB , i (i = the ‘O’ allele)

  • Antigen: Protein on surface of blood activates body immune system human blood is classified according to presence or absence of certain antigens

ABO Test 

  • Type A blood. Plasma contains antibodies against type B blood

  • Type B blood. Plasma contain Antibodies against type A Blood

  • Neither A or B antigen for Type O blood Plasma contains antibodies against both type A and B blood (Universal Donor)

  • Both A and B antigens type AB blood the Plasma does not contain antibodies against either (Universal Recipient)



Rule for Blood Types

  • A and B are codominant 

  • I A I A = Type A homozygous

  • I B I B = Type B homozygous 

  • I A I B = Type AB heterozygous

  • A and B are dominant over O 

    • I A i = type A heterozygous

    • I B i = type B heterozygous

    • ii = type O homozygous 




Linked Genes

  • Linked genes tend to be inherited together because the chromosome is passed along as a unit.

  • Results of crosses with linked genes are different from those expected according to independent assortment. 

  • Traits on same chromosome are linked

Crossing over

  • linked genes do not always stay linked

  • Because of crossing over in prophase I, some linked genes may end up on separate chromosomes

Chromosome Mapping 

  •  Genes that are far apart on a chromosome are more likely to separate due to crossing over 

  • Genes that are close together are less likely 

  • The frequency with which traits inherited together can be used to ‘map’ chromosomes

  • p arm is the part of chromosome above the centromere 

  • q arm is the part of the chromosome below the centromere

  • For sex linked traits, it is not possible for a male to be a carrier for a trait, as he has only one X chromosome. 

Thomas Hunt Morgan 

  • Morgan deduced that the gene with the white eyed mutation is on the X chromosome

    • Females (XX) may have two red-eyed alleles and have red eyes or may be heterozygous and have red eyes. 

    • Males (XY) have only a single allele and will be red eyed if they have a red-eyed allele or white-eyed if they have a white-eyed allele. 

    • Therefore, eye colour was a sex-linked trait (a trait controlled by the genes on the X or Y chromosome)







Unit 3

Evolution

  • Two Interrelated Phenomenon

    • Adaptation - Species Phenotypes the help them in environments

    • Speciation a new species from pre existing species 



Adaption

  • Helps organisms Survive reproduce in environments 

    • Structural - Process of Anatomy 

    • Physiological - Deals with organs function and body parts of different species 

    • Behavioral - How animals act 



Camouflage 

  • Defence tactic to disguise their appearance and blend with surroundings



Mimicry

  • A Harmless species resembles a harmful species 

Motion Mimicry

  • Mimic Inanimate Object 

Behavioural Adaptations

  • Nocturnal - Awake at night to conserve energy protect form dark 

  • Migratory - Migrate to areas with nutrients in different times of year or mating

Physiological Adaptations 

  • Venom - a Defence for some species 

  • Body Heat - Blood flow patterns change it maintain constant body temp

  • Very Cold - Shivering (muscle traction create heat)

    • Vasoconstriction - Blood vessels near skin constrict reduce heat loss

  • Very Hot - Sweating (Release water and air cool skin)

    • Vasodilation - Blood vessels expand release heat

Variation

  • Difference of species (Structural, behavioural or Physiological differences)

Environment 

  • Variation that have positive negative effect species survival 

    • Helpful variation likely survive for offspring

Variation Types

  • Continuous - Characteristics that change over time

  • Discontinuous - Limited possibility for species 

Allele Frequency

  • Frequency of Alleles for gene populations

Variation Sources 

  • Crossing Over

  • INdependent assortment 

  • Sexual Reproduction

  • Mutation - Change DNA Sequence (can be spontaneous or caused by UV rays or more)

Mutations

  • Gene able pass down 

    • Non Germline inheritable 

    • Germline Heratible 

Antibiotic Resistance 

  • Organisms that reproduce rapidly can see a change in allele frequencies quickly 

  • A gene that may have been rare, can become common in a short period of time if it provides a significant advantage 

  • Imagine a bacteria, exposed to an antibiotic for the first time

Selective Advantage 

  • Provide advantage (New or Improved functions) 

  • Genetic advantage over another organism

Evolutions

  • Change in allele frequency over time

Selective Pressure 

  • Condition certain that are put on organism by environment or other 

    • Environment select variation survives the best



Natural selection

  • Characteristics change over generation as organism have heritable traits survive and reproduce passing traits

Natural Selection Does Not 

  • Anticipate change in environment, have a direction or purpose or trait was advantageous may become irrelevant in future generations

Fitness

  • Contribution to next generation by producing offspring that survive to create offspring

Artificial selection

  • Selective pressure from humans lead to human traits

    • Agriculture - Crops

    • Domesticated Animals - Dogs



Evolution Theory

  • Evaluates Similarities differences to explain behaviour and whys in nature

Prevailing Idea of Time 

  • Immutable - Unchanged and Unchanging beliefs of characteristics of life forms

Archbishop James Ussher or Armagh

  • Irish theologian published calculation of earth's age determined to be created Sunday, october 23 4004 BC = Very Young

  • Late route into bible and mistaken be part of original scripture 

Challenging Prevailing Ideas of Time 

  • Fossil proved marking organism examined by early geologist 

  • And later proved forms of life and change of life (Diff organism exist diff areas)

1830 – Charles Lyell Uniformitarianism

  • Earth continuous change of surfaces and created an estimate of 35,000 years = Young

1866 - Lord Kelvin

  • Based on cooling rocks later revised estimate 15 - 20 years first scientific Method to estimate



1700s - Erasmus Darwin, Georges Buffon, and Carl Linnaeus

  • Suggested life originated single source slowly changed over time idea popular but could not suggest a mechanism which evolution occur 

1800s - Jean-Baptiste Lamarck

  • Suggest environment played key role in evolution species 

  • Able acquired trait and pass to offspring (Inherit Acquired traits)

  • If you don’t use certain body parts they disappear - Use Disuse Theory 

  • Only Genetic trait change level of DNA passed on

Adaption (Lamarck)

  • Explained evolution process species undergo adaptation (Help animals survive with physiological, Structural and Behavioural abilities)

  • Must be able to adapt to changing environmental conditions 

Charles Darwin 

  • Happened between 1809 - 1882 selected to be naturals on voyage, role was to observe, record, and collect specimens of rocks, minerals, plants and animals (1831 - 1836)

  • Biogeography - observation and analysis of geographic distribution of organisms

  • Darwin was put on to support biblical creation Didn’t occur

  • Ship was HMS Beagle from Europe to South America to Australia to Africa and back 

  • Darwin's 3 Patterns

    • 1. Species vary over time - fossils extinct species found and studied were similar to certain modern day creatures

    • 2. Species vary globally - related species similar habitats in different part of world are similar 

    • 3. Species vary locally - species that occupy different habitats a local environment different features most obvious species on Galapagos Island 

  • Darwin's Galapagos FIndings

    • This supported that own unique species of plants and animals due to different climates

Origin of Species 

  •  Economist Thomas Malthus wrote essay how population produce offspring their environment can hold

    • Darwin was influenced by idea that individuals competed with limited sources (Survival of the fittest)

  • Publish book on topic in 1859 



Charles Darwin: Natural Selection

  • Process individual inherit characteristics suited to environment (Leave more Adaption than less suited to environment species)

  • As species increase new gens will higher proportions of advantageous traits

  • And lead to new species 

  • Theory became by Alfred Wallace and Darwin in 1858 and created a book in 1859

Darwin's Observation And Inference

  • Obs 1 - Species vary 

  • Obs 2 - Variability can be inherited

  • Obs 3 - generations produce more offspring can survive pass on variation

  • Obs 4 - Population tend remain stable in size 

  • Inf 1 - Member same species compete survival

  • Inf 2 - Favourable environment likely survive and pass on trait survival not random

  • Inf 3 - offspring succeeding generation become more favourable variation more common

    • Favourable variation will become less common

  • Inf 4 - Change slow and Graduale

Unanswered Questions 

  • Traits parents still believed be blended in offspring

  • Productions lead to the entirely new structure 

Evidence of Evolution Clue #1: Anatomy 

  • Homologous Features - Similar Anatomy share common origin but serve different function in modern species 

  • Analogous Features - Similar structure but not share common origin 

Evidence of Evolution Clue #2: Embryology 

  • Embryonic Development - Stages of embryos of different organisms 

Evidence of Evolution Clue #3: Fossil Record 

  • Fossil found recent layer closely related species found today 

    • Not all species showed same time 

  • Transitional Fossil - link between two group organism 

    • Anatomical oddities have suggested evolutionary past 

      • Ex. hips in Whales and HUmans 

  • Vestigial Features - remnants of structures no longer serve function living organism in closely related species 

    • Ex. digits in horses vs. humans, wings in flightless insects 



Evidence of Evolution Clue #4: DNA 

  • 2 species have gene proteins with sequences match closely the sequence must have inherited from a relatively recent common ancestor

    • Ex. Human and primates close in DNA 5% difference in DNA

Evidence of Evolution Clue #5: Biogeography 

  • Environment close proximity more likely have related species 

    • Ex - Animal found on island strong similarities those found on nearest continent 



Microevolution

  • Evolution within a Population

Factors that Cause Microevolution 

  • 1. Population size small chance cause changes allele frequencies 

  • 2. Mating not random and preferred mates more likely pass genes

  • 3. Migration Occur change allele frequencies 

  • 4. Migration occur change allele frequencies

  • 5. Natural selection occur certain allele likely pass next generation

Genetic Drift

  • Defines as change allele frequency result of chance 

    • Small Population 

  • Types of Genetic Drift:

    • Bottleneck Effect 

    • Founder Effect 

Bottleneck Effect

  • Dramatic, often temporary reduction population size usually result significant genetic drift 

  • Cause natural disaster Famine some other servere event 

  • Small Population survive responsible for establish new population

  • Ex. Northern Elephant Seal 

    • Overhunted to 20 people an descended from that

Founder Effect

  • Genetic Drift result small number individuals separate their original population find new population

  • Isolate human population very high incidence rate genetic disorder 

Gene Flow

  • Mating opportunities not random preferred mates pass alleles more frequent than less preferred individuals 

  • Individual migrate remove allele one population and add them to another 

  • Gene Flow - Movement alleles within a population due non-random mating migration

    • Cause genetic info shared amongst populations reduce overall differences 



Mutations

  • Permanent change in DNA 

    • Neutral - No Affect

    • Beneficial 

    • Harmful 

  • Genetic mutation occur allele created thereby changing frequency both new original alleles 

  • Mutation happens in gamete (vs. Somatic) cells can be passed onto future generations

  • Ex. 2004 study three-spined stickleback mutation account most its bone structure

    • Spines may help protect being eaten by predator 



Natural Selection

  • Many Types

    • Stabilizing Selection

    • Directional Selection

    • Disruptive Selection

    • Sexual Selection



Stabilizing Selection

  • Tend occur population environment stable and unchanging over long period of time 

  • Selective pressure variation phenotypes narrow over time 

    • Ex. Human Birth Weight 



Directional Selection

  • Favours phenotypes at one extreme over the other result distribution phenotype shifting that direction 

    • Ex. Salmon Fishery B.C. (Small size adults became favourable due net fish)



Disruptive Selection 

  • Extreme phenotypes are favoured

  • Produce bimodal distribution 

    • Ex. African seedcracker finches 

      • Common phenotype: slender/small bill and heavier/large bills

      • Medium bill not favoured - Compete with small billed birds smaller seeds

      • Medium billed birds require more energy smaller billed birds 

Sexual Selection  

  • Favour selection any trait influence mating success of individuals

  • Tend compete mates while female tend choosing 

    • (Female invest reproductive amd rearing)

      • Ex. Mammals (show preference for male phenotype can cause)

  • Sexual Dimorphism - great difference between male and female species

    • Ex. Red winged 

Speciation

  • A biological concept of a species is a population or group of populations that are able to interbreed, under natural conditions to produce fertile offspring. 

  • The selective mechanisms that favour beneficial traits, natural selection, are also responsible for speciation (the formation of an entirely new species). 

  • Evolutionary changes that occur at the species level are known as macroevolution.

Reproductive Isolating Mechanisms 

  • Biologist on morphological feature from fossil record distinguish thousands of different species 

  • Living population are morphologically similar behavioural other biological methods needed distinguish species 

  • Method use identify species reproductive isolating mechanisms (any behavioural, structural or biochemical trait prevent individual diff species reproduce successfully together)

  • Two types isolating mechanisms 

    • prezygotic isolating mechanisms

    • postzygotic isolating mechanisms



Prezygotic Isolating Mechanisms 

  • prevent interspecies mating and fertilization: 4 types isolation that prevent 

Ecological Isolation

  • Species occupy separate habitat or niches do not encounter another reproduce due some geographic or ecological barrier 

    •  Ex. ground squirrel occupy different habitats

Temporal Isolation 

  • When two species found same areas but incapable mating due to different reproductive cycles

    • Ex. Red and black sea urchin live same location, but release their gametes at diff time

Behavioural Isolation

  • Distinct mating ritual one species may prevent members another species recognize or selecting a mate 

  • Ex. Male jumping spider dance (shake legs female repsong diff species fin to respond)

Mechanical Isolation

  • Structural difference reproductive organ prevent successful fertilization 

    • Ex. Flowering plants evolve species structure adapt to earring pollinators find through echolocation

    • Also pollen one species not able form pollen tube lands on stigma diff species

Gametic Isolation

  • Prevent reproduction molecular level 

  • Ex. coral reefs species external fertilization release gametes simultaneously trillions sperm eggs may be shallow water one time sperm egg same species recognize each other by molecular markers

Postzygotic Isolating Mechanisms

  •  hybrid zygote develop into healthy fertile adults three likely cases occur ensure hybrid does not reproduce 

  • Zygote Mortality - Result of chromosomal incompatibility

  • Hybrid Inviability - when embryo does develop hybrid experience reduce fitness often early death 

  • Hybrid Infertility - Develops mature adult but unable to undergo successful meiotic division, and is unable produce offspring  (Seen in donkey - horse hybrid: Mules)

  • Hybrid Breakdown - Offspring is inable later generations experience fertility issue



Modes of Speciation 

Allopatric Speciation 

  • Population diverge gene flow between is restricted geographic isolation often first step in allopatric speciation 

    • Ex. Galapagos finches and tortoises

Sympatric Speciation 

  • Member of population develop some genetic difference prevent them from reproducing parent type 

  • Mechanisms occurred several time in plants where failure reduce chromosome number result polyploid plant that reproduce successfully only with polyploids

  • Cause instant speciation due nondisjunction

  • Sympatric Speciation - also occurred cichlid fish in Lake Victoria in Africa 

Parapatric Speciation 

  • Two separate regions occur with zone hybridization where two species overlap

    • Ex. Bullock's Orioles and Baltimore Orioles




Unit 4 

Macronutrient and Micronutrients Key Terms 

  • Macronutrient - nutrient needed in large amounts in our diet

  • Micronutrient - nutrient needed in small amounts in our diet

  • Polymer - molecule made up of many subunits

  • Monomer - a subunit of a polymer

  • Condensation reaction (dehydration synthesis) - reaction in which monomers are joined, with water as a byproduct

  • Hydrolysis reaction - reaction in which complex biological molecules are broken down into simpler molecules using water

  • Catalyst - speeds up a reaction without being consumed in the reaction

  • Enzyme - protein catalyst. Enzymes often end in the suffix '-ase', eg. DNA polymerase (enzyme that makes DNA polymers)

  • Hydrophobic - water fearing (not water soluble)

  • Hydrophillic - water loving (water soluble)

Carbohydrates 

  • Monosaccharides 

    • Single Sugars

      • Ex. Glucose =, fructose, dextrose

  • Disaccharides

    • Combination of two monosaccharides

      • Ex. Sucrose, Lactose, Maltose

  • Polysaccharides

    • A Polymer of many monosaccharides

      • Ex. Glucose, amylose (Starch), cellulose, chitin

Formation of Polymers 

  • Dehydration Synthesis  (Condensation Reaction) - Building monomer to build polymer

  • Hydrolysis Reaction - Breaking down macromolecules using water and enzymes

Lipids

  • Fats, Oils and Waxes (Depending on the state and room temperature

    • Made of triglycerides (Glycerol and three fatty acids)

    • Glycerol + Fatty acids are condensation reaction

Fatty Acids 

  • Hydrocarbons chain in the fatty acid can either be; 

    • saturated (containing only single bond) 

    • unsaturated (containing one or more double bonds between carbons)

Lipids

  • Phospholipids 

    • Amphiphilic molecule containing glycerol, 2 fatty acids, and polar ‘head’

  • Steroids 

    • Multi-ringed molecule often used as chemical messenger (Hormones)

      • Ex. Cholesterol, testosterone, progesterone 

Proteins 

  • Made of chains of amino acids, There are 20 different amino acids (8 are essential, meaning that it cannot be made by the body)

  • Each amino acid has an amino group, a carboxyl group and a unique portion called the R-Group 



Polypeptides 

  • Many amino acids join together (via dehydration synthesis reactions) to form polypeptides (the bond between two amino acids is called a peptide bond)

Vitamins 

  • Organic molecules required in tiny amounts by an organism 

Minerals

  • Inorganic trace elements required in small amounts



Digestive System

Ingestion and Digestion - The Mouth 

  • Food enter mouth teeth mechanical digestion teeth are:

    • Incisors - cut food into smaller pieces

    • Canines - Pierce and tear food 

    • Molars - Crush and grind food 

  • Chewing stimulate salivary glands to secrete saliva

  • Saliva = water, mucus, and enzyme amylase (Breaks down starch into simple sugar)

  • Tongue move food form bolus (Ball)

Digestive Enzyme 

  • Enzyme protein catalyst and that catalyst speed up reaction without being consumed in reaction 

  • Enzymes act on substrates often having suffix ase (Ex. Lactase - substrate is lactose)

  • Enzymes need be activated to function properly 

Enzyme Activity 

  • Affect by environment factors such as temperature

    • ↑ temp, ↑ rate of reaction 

    • ↓ temp, ↓  rate of reaction

  • However high temp cause enzyme to denature and enzymes become less effective 



PH

  • Enzyme have optimal Ph level in which they work best (Ex, Stomach vs. SI)




Substrate Concentration

  • Better chance will find enzyme bind to therefor products more faster

  • There ar elot more substrate enzyme the chemical reaction not get faster indefinitely it reach a maximum 

Salivary Gland 



The Pharynx and the Esophagus 

  • Pharynx receives food from mouth and air from nose 

  • Bolus moves past opening trachea protected by flap skin called epiglottis (Swallowing Reflex) down esophagus by peristalsis

  • Peristalsis is wavelike series (smooth Muscle contraction)

Digestion - The Stomach

  • Food moving into out stomach regulated by sphincter 

  • When sphincter contract opening closes 

  • Esophageal sphincter connect esophagus and stomach 

  • The Pyloric Sphincter deals with stomach and small intestine only open when ready for food

The Stomach 

  • Three layer muscle churn mechanical digestion 

  • Stomach lining made gastric cells make gastric juice enzymes and mucus 

  • Enzymes begin chemical digestion in stomach precursor enzyme pepsinogen is inactive change into active form, pepsin by acidic environment (HCl) Pepsin breaks down proteins (From proteins to peptides)

    • Carbohydrases (Digest Carbs)

    • Proteases (Digest proteins) (Breakdown polypeptides to peptides)

    • Lipases (Digest Lipids)

    • Peptidases (peptides into amino acids)

  • Hydrochloric acid destroys foreign substances such as bacteria that are ingested with food. 

  • The high acidity inside the stomach (pH 2.0 to 3.0) can kill pathogens. 

  • The mucus protects the lining from the strong acid. 

  • If the mucus barrier is damaged, an ulcer results: gastric juice digests stomach lining.



Ulcer

  • Stress cause to much gastric Juice release 

  • Food in stomach, the excess acid can burn through mucus layer cause ulcer

  • Ulcer cause by bacterial infection, high acid diets, and overuse of certain medications

Small Intestine 

  • Leaves stomach as chyme (Soupy mixture partially digested food enzyme and acid)

    • 3 section small Intestine

      • Duodenum - Chemical Digestion

      • Jejunum - Chemical DIgestion and Absorption

      • Ileum - Absorption

    • Breakdown continues SI: Carbohydrates, proteins, and lipids are broken down in SI with the help of secretions from ACCESSORY ORGANS

      • Pancreas release pancreatic fluid rise PH level in duodenum

      • PH inactivates pepsin in chyme and correct PH for further breakdown of food SI

SMALL INTESTINE Trypsin & Erepsins

  • Far protein is somewhat broken down in the stomach via pepsin. But more protein digestion need to occur

  • Pancreas secretes enzymes for final digestion of all component of food

    • Digest Proteins - Trypsin breaks lon polypeptide chain into short ones

    • Erepsin (A peptidase) break short polypeptide chains into individual amino acids



Small Intestine Amylase 

  • Digest Carbohydrates - Pancreatic amylase breaks down starch into glucose molecules



SMALL INTESTINE CCK & Bile

  • Accessory organs help in fat digestion 

    • Liver produce bile, stored in gallbladder, Fat enter SI, hormone CCK (From SI) is released 

    • CCK carried gallbladder and triggers release bile salts into SI

    • Fat digestion physical breakdown since chemical bond not broken 

    • Fat can be digested in SI chemical digestion 



SMALL INTESTINE Lipases & CCK

  • Digest Lipids - fat - digesting enzymes, lipases are used 

    • Pancreatic Lipase - break down triglycerides into glycerol and fatty acids

    • Phospholipase - Break down plasma membrane of cells from food you ingest



Small Intestine Liver 

  • Liver has many function 

    • Conversion glucose to glycogen and vice versa, red cell decompensation

    • Plasma protein synthesis 

    • Detoxification and bile production 

Small and Large Intestines 

  • Usable product digestion of glucose, fatty acids, and amino acids able remove SI through absorption and transported when needed 

  • Small Intestine made up Villi are fine thread-like extensions membrane increase the surface area for absorption 

  • Glucose and amino acids are absorbed into the capillary network. Once absorbed, they make their way to the liver for modification before it is sent throughout the body. 

  • Fats are absorbed into the lacteals. The contents eventually reach the circulatory system.

Large Intestine 

  • The undigested particles travel to the large intestine (through the ileocecal valve) where more absorption can occur. 

  • Water and vitamin absorption will occur here in the colon.

  • As wastes build up in the large intestine, the nervous system sends a signal to the brain to remove the waste from the body via the rectum. 

  • Feces odour and colour is due to the “good” bacteria in your colon that finish the digestion process. 

The Circulatory System 

  • The circulatory system is the transport system of the body and has several functions: 

    • 1. Transportation of oxygen, carbon dioxide, nutrients and wastes 

    • 2. Maintenance of body temperature 

    • 3. Circulation of hormones 

    • 4. Protects against blood loss

    •  5. Protects against disease-causing agents that enter the body

Structure of the Circulatory System 

  • The circulatory system is actually two systems in one. 

    • 1. The Pulmonary Circuit 

      • The right side of the heart pumps blood to the lungs.

      • The blood picks up oxygen from the lungs and returns it to the left side of the heart. 

      • Heart to lungs, lungs to heart



Structure of the Circulatory System 

  • 2. The Systemic Circuit 

    • The left side of the heart pumps oxygenated blood to the body. 

    • The blood returns to the right side of the heart without oxygen (deoxygenated). 

    • Heart to body, body to heart



Pulmonary and Systemic Circulation 



Three Components to the Circulatory System 

  • Blood

  • Blood Vessels 

  • Heart 

Blood Components 

  • Plasma 

    • 55% of Total Blood Volume 91% Water 

    • 7% Blood Proteins (fibrinogen, albumin, globulin)

    • 2% 

      • Nutrients (Amino Acids, sugars, lipids)

      • Hormones (erythropoietin, insulin, etc)

      • Electrolytes (Sodium, Potassium, Calcium, etc)

  • Cellular Components 45% of Total Blood Volume 

    • Buffy Coat

      • White Blood Cells (7000 - 9000 per mm ^ 3 of blood) Platelets (250000 per mm ^ 3 of blood)

    • Red Blood Cells (RBCs)

      • About 5,000,000 per mm ^3 of blood

      • Also called Erythrocyte

Plasma 

  • Plasma transports materials needed by cells and materials that must be removed from cells 

    • 92% Water 

    • 6-8% Protein 

    • 0.8% Salts 

    • 0.6% Lipids 

    • 0.1% Glucose (blood sugar) 

  • There are three types of plasma proteins: 

    • Albumins (osmotic balance)

    • Globulins (antibodies and immunity) 

    • Fibrinogens (blood clotting)

Erythrocytes: Red Blood Cells

  • Non-nucleated, biconcave discs 

  • Contain hemoglobin, (approx. 280 million hemoglobins in each cell) 

  • Transport oxygen and CO2 in the blood back and forth from tissues and the lungs 

  • Live on average for 120 days

  • Men Tend to have more red bloods cells of blood than women do  per mL

    • Average male – 5.5 billion rbc’s / mL 

    • Average female – 4.5 billion rbc’s / mL 

    • High altitude – 8 billion rbc’s / mL



Leukocytes: White Blood Cells

  • Have nuclei 

  • Participate in protecting the body from infection 

  • Some perform phagocytosis (engulfing and destroying pathogens) 

  • Include a variety of different cells: 

    • T Lymphocytes (T Cells) - responsible for fighting off infected cells, 

    • B Lymphocytes (B Cells) - responsible for making antibodies 

    • Other Leukocytes - Monocytes (Macrophages), Basophils, Eosinophils, Neutrophils 

  • Platelets - involved in blood clotting (not leukocytes, but part of the buffy coat)

Blood Vessels 

  • Arteries

    •  Bring blood away from the heart

  • Venule 

    • Very tiny vein branch 

  • Three distinct layers!

    • Outer (connective tissue)

    • Inner (connective tissue)

    • Middle (muscle fiber and elastic connective tissue)

    • As the heart contracts, blood surges through arteries, and they stretch; this produces a pulse

    • Muscle layer in the artery contracts after blood passes, helping to push blood along

    • Aorta → Arteries → Arterioles

    • Arterioles can vasoconstrict and vasodilate

  • Veins

    • Bring blood back to the heart

    • Not as thick as arteries

    • Venules → Veins → Superior/Inferior Vena cava

    • The middle layer of veins is much thinner than arteries

    • Lack muscular layer - Rely on muscular action of surrounding muscle tissue to help push blood back to the heart

    • Valves prevent backflow

  • Capillaries 

    • Site of gas exchange between blood vessels and lungs/body 

    • Have a thin wall, 1 layer of cells thick

Blood Vessel 

Temperature Regulation 

  • Our bodies control our temperature by regulation how much blood flows near the skin surface 

    • Vasodilation - widening of blood vessels near the surface, heat can easily escape (cooling method) + evaporation of sweat! 

    • Vasoconstriction - narrowing of vessels near the surface, heat loss is minimized (warming method) + shivering!

Heart Anatomy 

  • Heart has 4 chambers 

    • 2 Atria 

    • 2 Ventricles 

  • Blood from veins collects in the atria 

  • Blood passes through a valve to the ventricles 

  • Ventricles contract rhythmically, and pump blood to the arteries 

    • R Ventricle - pulmonary arteries 

    • L Ventricle - aorta (systemic circuit)

Heart Anatomy 

  • Valves -> flaps of tissue that keep blood from flowing backwards 

    • The atrioventricular valves (AV) prevent blood from flowing back from the ventricles into the atria 

      • Tricuspid - 3 flaps, RA to RV 

      • Bicuspid - 2 flaps, LA to LV 

  • The semilunar valve keeps blood from flowing back from the heart arteries into the ventricles. Pulmonary – prevents backflow from pulmonary artery to RV Aortic

  • prevents backflow from aorta to LV

Heart Pathway 

  • Blood enters RA (right atrium) from the Superior and Inferior Vena Cava 

  • RA fills, contracts, blood  enters RV (Right Ventricle) (Tricuspid Valve)

  • RV fills, contract, bloods enters the pulmonary arteries (Pulmonary Valve)

  • Blood reaches the lungs become oxygenated 

  • Blood returns to the LA through the Pulmonary Vein 

  • LA fills up contracts empties into the LV, Bicuspid Valve shuts 

  • LV fills up contracts and sends blood through the aorta, aortic valve shuts

  • Blood Heart Pathway to travels to every cell of the body to drop off oxygen and pick up carbon dioxide








Heart Pathway  





Heart Anatomy 

  • Control of the Heart Rate is controlled by ‘nodes’; groups of cells that generate a nerve impulse 

    • Sinoatrial node (SA) - located in the upper right atrium 

    • Atrioventricular node (AV) - located between the right atrium and ventricle 

  • SA node sends a signal to the AV node 

  • AV node relays the signal through the fibres called the bundle of His, which divides into two branches 

  • The branches further divide into Purkinje fibres which initiate the simultaneous contraction of both ventricles

  • Myocardium (Heart Muscle)

  • Pacemaker help in the are known as sinostiral (SA Node)

  • Bundle of His

The Heartbeat and the ECG

  • “LUB” – closing of the AV valves 

  • “DUB” - closing of the semilunar valves 

  • ECG = Electrocardiogram 

  • Wave has several components, designated by the letters P, QRS, T 

  • Each component relates to a different part

  • Myocardial Infarction - ANother name for Heart Attack 

Blood Pressure 

  • It is the force exerted against the walls of the blood vessels 

  • When measuring BP using a sphygmomanometer (BP cuff), two values are given in mmHg: 

    • Systolic Pressure: Systole phase (contraction of ventricles) 

  • Diastolic Pressure: Diastole phase (ventricles fill with blood) 

  • Below 120/80 is considered a healthy BP 

  • BP is affected by many factors (diet, stress, genetics) but elevated BP for long periods of time (hypertension) can lead to serious health issues (heart attack, stroke). 

Cardiac Output and Stroke Volume 

  • Cardiac Output (Q) –> blood pumped by the heart in mL/min 

  • Cardiac Output = Heart Rate x Stroke Volume 

  • Heart Rate = Beats per minute (bpm) 

  • Stroke Volume = Blood pumped by the left ventricle per beat (mL/beat) 

  • Q = HR x SV 

  • SV is impacted by strength of contraction by the ventricles, and how easily the heart fills with blood 

  • Fitness can increase SV, and lowers resting heart rate (heart will not have to work as hard) 

  • Average person: 

  • Q = 70 beats/min X 70 mL/beat = 4900 mL/min



Cardiovascular Disorders 

  • CAD - Coronary Artery Disease 

    • Gradual Blockage of Coronary arteries 

  • Heart Attack 

    • Complete Blockage of one or more coronary arteries 

  • Stroke 

    • Blockage of a brain artery





Four Respiration Processes 

  • Breathing (ventilation): air in to and out of lungs  

  • External respiration: gas exchange between air and blood  (Happens at alveoli)

  • Internal respiration: gas exchange between blood and tissues (Capillaries and cells) 

  • Cellular respiration: oxygen used to produce ATP, carbon dioxide as waste

Human Respiratory System  

Components of the upper Respiratory Tract 

  • Passageway for respiration 

  • Receptor for smell 

  • Filters incoming air to filter larger foreign material (Nose hairs, Cillia) 

  • Moistens and warms incoming air (Capillaries that line the nasal cavity)  

  • Resonating chambers for voice 

  • Pathway of air: 

    • 1. Air enters the nose/mouth and is moistened, warmed and cleansed. 

    • 2. Air is passed through the pharynx (common site for food and air) to the glottis (opening of the windpipe)





Lower Respiratory Tract 

  • Functions:  

    • Larynx: maintains an open airway, routes air appropriately, assists in sound production  

    • Trachea: transports air to and from lungs  

    • Bronchi: branch into lungs  

    • Lungs: transport air to alveoli for gas exch 

    • Pathway of air: 

      • 3. Air enters the windpipe, passes the larynx, into the trachea, then bronchi, to the bronchioles, then finally ends at the alveoli. 

Process of Breathing: Pressure Gradient

  • Inspiration/Expiration: air in/air out  

  • Air always move from high to low pressure  

  • Cycle:  

    • Relaxed state: diaphragm and intercostal muscles relaxed  

    • Inspiration: diaphragm contracts, pulling muscle down, intercostal muscles contract elevating chest wall and expanding volume of chest, lowering pressure in lungs, pulling in air  

    • Expiration: muscles relax, diaphragm resumes dome shape, intercostal muscles allow chest to lower resulting in increase of pressure in chest and expulsion




Respiratory Cycle 





Measurement of Lung Function 

  • Lung Volume and Vital Capacity 

    • Tidal volume: volume of air inhaled and exhaled in normal breathing when the body is at rest  

    • Inspiratory reserve volume: the amount of air that can be inhaled beyond a normal breath  

    • Expiratory reserve volume: the amount of air that can be exhaled beyond a normal breath  

    • Vital capacity: total volume of gas that can be moved in and out of the lungs 

      • Tidal + Inspiratory Reserve + Expiratory Reserve= VC 

    • Residual volume: the air that remains in the airways and does not participate in gas exchange (keeps the lungs from collapsing)



Measurement of Lung Capacity 




Gas Exchange and Transport a Passive process 

  • Each gas in a mixture exerts its own pressure (partial pressure).  

  • The differences between oxygen and carbon dioxide concentrations are measured by partial pressures.  

  • Respiratory pigments increase the oxygen-carrying capacity of the blood. Humans have the red-coloured pigment hemoglobin as their  respiratory pigment. 

Gas Exchange Between the Blood and Alveoli 

Gas Exchange and Transport: Oxygen 

  • At the alveolus, the surrounding capillary has a low partial pressure of oxygen (as it contains carbon dioxide waste). As a result, oxygen diffuses into the capillary from the alveolus after inhalation.  

  • The partial pressure of oxygen is higher in the capillary than the body tissues, causing the dissociation (split) of oxygen from the hemoglobin, and the oxygen diffuses into the tissues. 



Gas Exchange and Transport: Carbon Dioxide

  • Carbon dioxide’s partial pressure in metabolically active cells is much greater than in capillaries, so carbon dioxide diffuses from the cells into the capillaries.  

  • 23% of the body’s CO2 combines with hemoglobin to form carbaminohemoglobin. The rest of the CO2 is carried through the bloodstream.  

  • At the alveolus, the partial pressure of carbon dioxide is higher in the capillary than in the alveolus. As a result, carbon dioxide diffuses in the alveolus and is exhaled.