diversity of living things

taxonomy

science of classifying species

species

a group of related organisms that produce fertile offspring

• most specific taxon

classificantion

the process of grouping things according to similarities

• people have been doing this for a long time, including aristotle

carl linneaus

• swedish scientist who made binomial nomenclature

• starting point for how things are done in modern day

binomial nomenclature

• each organisms has a genus and species name

• first name is genus, capitalized

• second name is species, lower-case

• typed: italics

• hand written: underlined

genus

taxonomic group of closely related species

biotic

• living

• made of one or more cells

• able to:

  • respond to stimuli from surroundings

  • use chemicals to grow and reproduce

  • maintain stable internal living conditions

abiotic

• not made of cells

• unable to:

  • respond to stimuli

  • grow and reproduce

taxon

level of classification

levels of classification (8 taxa)

• domain

• kingdom

• phylum

• class

• order

• family

• genus

• species

info used by taxonomists to classify organisms

• structure (skeleton, leaf anatomy, gram positive)

• behavioral info (sounds, movements, social interactions)

• cytological info (prokaryotic/eukaryotic, chromosome number)

• embryological info (appearance of organisms in early stages of development)

• physiological info (biochemicals like DNA, RNA, proteins)

determining how species are related

• DNA evidence

• physiological evidence

• anatomical evidence

anatomical evidence of relationships

• refers to physical characteristics

  • size. shape, features, etc

  • fossils

• embryological development also indicates shared evolutionary ancestry

physiological evidence of relationships

• refers to the functioning of organisms, including the proteins they make

• genes determine the proteins a species makes

  • by comparing proteins among different species, the degree of genetic similarity/difference can be determined

DNA evidence of relationships

• refers to similarities in the long chains of molecules (nucleotides) that make up genes

• closely related species will have similar DNA sequences

• advances in tech have resulted in the reclassification of many species

phylogeny

science that deals with evolutionary relationships between species

phylogenetic tree

way of showing evolutionary relationships

clade

• taxonomic group that includes a single ancestor species and all its descendants

• species are grouped into this on a phylogenetic tree

• a node on the tree represents an ancestor species

structural diversity

• biological diversity that is seen in the structural forms of living things

  • internal cell structure to body morphology

• every species is made of DNA and cells

kingdoms timeline

• originally just animals and plants

• 1860s added protists

• 1930s added bacteria

• 1960s added fungi

• 1990s divided bacteria into bacteria and archea

domain

• highest rank of taxonomy/most general taxon

• bacteria

• archea

• eukarya

characteristics of kingdoms

• cell type

  • prokaryotic cell (small, simple cells without membrane bound nucleus)

  • eukaryotic cell (large, complex cell with membrane bound nucleus)

• number of cells

  • unicellular

  • multicellular

• cell wall material

  • peptidoglycan, cellulose, chitin, etc

• nutrition

  • autotroph (obtains energy by making its own food)

  • heterotroph (obtains energy by consuming other organisms)

• primary means of reproduction

  • asexual (makes genetically identical offspring)

  • sexual (2 parents organisms produce offspring, hybrid of parents)

6 kingdoms

• bacteria

• archea

• protists

• plants

• fungi

• animals

archaea

• domain: archaea

• cell type: prokaryotic

• number of cells: unicellular

• nutrition: heterotrophs (uniquely methanogenic), autotrophs

• cell wall: not made of peptidoglycan, occasionally no cell wall

• asexual, binary fission

• habitat: extremophile (extreme environments)

bacteria

• domain: bacteria

• cell type: prokaryotic

• unicellular

• heterotrophs, autotrophs (uniquely photosynthetic)

• cell wall: made of peptidoglycan

• asexual, binary fission

• habitat: versatile mesophile (non-extreme environment)

structure of prokaryotes

• cell wall provides structural support and protection

• DNA forms a ring, not strand

  • single chromosome

• some bacteria have a flagella for movement

• plasmid, small loop of DNA

  • contains different genes than the ones found on the chromosome

prokaryotes cell shape

• cocci - spherical shaped

• bacilli - rod shaped

• spirilla - spiral shaped

prokaryote prefixes

describe how they live

• mono - live as single cells

• diplo - live in pairs

• strepto - live in linear chains

• staphylo - live in clusters

gram staining

technique that helps classify and identify prokaryotes (specifically bacteria)

• gram positive: absorb purple stain, have thick peptidoglycan layer

• gram negative: stain pink, have thin peptidoglycan layer (all archaea would be gram negative)

bacteria nutrition

• can be both autotrophic and/or heterotrophic

• photosynthesis used by some bacteria

• process of using sun to convert CO2 into water and sugar

• produces oxygen as a by-product

  • these bacteria create most of the atmospheric oxygen

  • cyanobacteria are photosynthetic bacteria

archaea nutrition

• can be both autotrophic and/or heterotrophic

• methanogenesis (heterotrophic)

  • unique to archaea

  • produces methane as a by-product

  • found in digestive tract of cattle

how does livestock farming play a role in climate?

• increased farming of large animals would result in an increase of methane gas in the atmosphere

• methane is a green house gas which contributes to climate change

binary fission

• cell divides into genetically identical cells

• used by archaea and bacteria

• DNA replicates, moves to opposite poles, middle pinches in, cell separates into two daughter cells

endospores

• unique to bacteria

• survival strategy

• when environmental condition are not favorable bacteria creates a tough outer structure to hold its genetic material

  • once conditions are favorable it turns into a bacteria

archaea habitats

• they are extremophiles

• thermophiles - heat lovers

• acidophiles - acid lovers

• halophiles - salt lovers

extremophiles

live in extreme environments

bacteria habitats

live in moderate conditions (mesophiles)

bacteria/archaea and human health

• clostridium botulinum

  • bacteria that causes food poisoning

• streptococcus pyogenes

  • gram positive bacteria that causes strep throat

• streptococcus mutans

  • gram positive bacteria that causes tooth decay

• no known archaea can harm human health

identifying organisms tools

• smart phone apps

• dichotomous keys

• field guides

smart phone apps

good choice when:

• when you have your phone and access to the internet

• when you know of an app for general type of organisms (ex: Shroomify for fungi, Merlin for bird songs, etc.)

dichotomous key

• tool that uses a series of yes/no questions to guide you toward the identification of an organism

• good choice when

  • your list of possible organisms is short

  • when you want to learn about small differences between organisms

rules to follow when using/creating a dichotomous key

• always read both choices

• understand the meaning of the terms

• when measurements are given, measure

• living things are always variable, use constant characteristics, make multiple observations

field guides

good choice when:

• you have one for your local area (either print or online)

• when you are looking to learn more about the organism

characteristics of fungi

• domain: eukarya

• cell type: eukaryotic

• number of cells: most are multicellular

  • yeast are unicellular

• nutrition: heterotrophic, by absorption

• cell wall: made of chitin (carbohydrate)

• reproduction: asexual and/or sexual

structure of fungi

• hyphae: thread-like filament that makes up basic structure inside fungi

• mycelium: complex network of branching hyphae

  • grow in nutritious substances

  • increase surface area for absorption of nutrients

• fruiting body: spore-producing reproductive structure

  • what you see above ground

fungi nutrition

• fungi get their nutrients by absorbing organic material from their environment

• release digestive enzymes outside of the fungi which breakdown complex molecules into smaller organic components

• organic components are then absorbed through the cells walls

fungi nutrition types

• parasitic

• predatory

• mutualistic

• saprobial

parasitic nutrition

• absorb nutrients from living cells of host organism

• usually live inside organism

• ex: cordyceps

  • invade insects body and emerge through

predatory nutrition

• soil fungi

• mycelia have specialized structure for trapping prey

• ex: arthrobotrys

  • traps nematodes that live in soil

mutualistic nutition

• form partnerships with organisms

  • called mycorrhiza

• mycelia cover that roots of plants and increases absorption of plant roots

• fungi receive sugar from plants

saprobial nutrition

• saprobes absorb nutrients from dead or decaying matter

• essential for recycling nutrients in ecosystems

fungi reproduction

• all fungi reproduce by producing spores

• spores are carried by the wind or water

  • when spores land in a life-supporting environment (warm and moist with food) they begin to produce new fungi

• fruiting body produces spores

asexual reproduction of fungi

produce genetically identical spores (ex: budding in yeast)

sexual reproduction of fungi

• fungi are not male or female, they are plus or minus

  • hyphae of plus fungi fuse with hyphae of minus fungi

  • spores are produced are genetic hybrids of each fungi

characteristics of animals

• domain: eukarya

• cell type: eukaryotic

• number of cells: multicellular

• nutrition: heterotrophs

• cell wall: no cell wall (have cell membrane)

• reproduction: sexual

• also

  • have ability to move in at least one stage of life

  • produce an embryo that undergoes stages of development

body plan of animals

body plan is the overall organization of an animals body. used for classification

• invertebrate vs vertebrate

• symmetry

• segmentation

• movement

invertebrate

• an animal that does not have a backbone

• ex:

  • sponges

  • butterfly

  • clams

  • worms

  • sea star

  • jellyfish

vertebrate

• animal with an internal skeleton and backbone

• ex:

  • fish

  • humans

  • amphibians

  • kangaroos

  • reptiles

  • birds

symmetry in animals

• refers to the arragement of organs or appendages (arms/legs) an animal has

• radial symmetry

• bilaterial symmetry

• sea sponge in an exception, it has no symmetry

radial symmetry

body can be divided into many equal parts through a central point

• ex: star fish

bilateral symmetry

body can be divided into two equal parts through a central point

• ex: insects

segmentation

• division of the body into repetitive sections or segments

• pros:

  • allows for more effective movement. each section moves independently

  • if a single segment is damaged, the other segments can still function properly

movement

• animals have two types of tissue not found in any other kingdom

• nerve and muscle tissue

  • allow for development of complex and fast movements

  • nervous system ranges from simple (nerve net) to complex (network of nerves, brain, spinal cord)

• if an animal is stationary as an adult, it had the ability to move as a juvenile (earlier development)

invertebrate: sponges

• marine and freshwater environments

• only animal with an asymmetrical body

• no tissues (nervous or muscle)

• stationary adults

• feed by trapping food particles as water passes through their internal channels of their bodies

invertebrate: cnidarians

phylum cnidaria

• have muscle tissue and simple nervous system (nerve net)

• radial symmetry

• two body forms that feed in different ways:

  • polyps: attach to a surface and extend tentacles upwards, waiting for pray (stationary)

    • ex: freshwater hydras, coral

  • medusas: swim and capture prey by stinging it with tentacles

    • ex: jellyfish

invertebrate: worms

• bilateral symmetry

• has muscle tissue and simple nervous system\

  • developed brain-like concentration of cells and eyespot in head area.

• mainly classified through whether it has a segmented body

• ex:

  • flatworms (Phylum Platyhelminthes)

  • earthworms (Phylum Annelida)

invertebrate: arthropod

phylum athropoda

• exoskeleton: protects the animal and provides points of attachment for muscle that move legs

• separated based on how many body segments it has

important vertebrate features

• phylum chordata

• all have bilateral symmetry

  1. notochord: rod-shaped structure used for the attachment of movement muscles

     • replaced by the spine

  2. nerve cord: tube shaped cord present in embryo

     • becomes the brain and spinal cord

vertebrate: amphibian

• class: amphibia

• fossil evidence shows amphibians were the first vertebrates to begin living on land

  • still need a wet environment to stay moist

• tetrapod

tetrapod

vertebrate with two pairs of limbs; an amphibian, reptile, bird, or mammal

vertebrate: reptiles

• class: reptilia

• developed to live fully in terrestrials environments

• waterproof body that prevents dehydration

vertebrate: bird

• class: aves

• fossil and physiological evidence suggests that birds and dinosaurs are related

  • also suggests birds are modified dinosaurs

• birds are endotherms

  • fish, amphibians and reptiles are ectotherms

• have hollow bones and compact body to reduce body weight, advantage for flight

endotherm

generate their own body heat

ectotherm

absorb heat from surroundings, can’t generate their own

vertebrate: mammals

• class: mammalia

• most distinctive features of mammals

  • all have bodys covered in hair

  • mammary glands - produce milk to feed their young

• endothermic

• monotremes, marsupials, placentals

monotreme

• mammals that lay eggs

• only 2: platypus and spiny anteater

marsupial

• pouched mammals

• they are born early and continue development in the mothers pouch

  • ex: kangaroo, koala, opossum

placental

• have a placenta, grow young in uterus

  • bears, bates, whales, humans

characteristics of plants

• domain: eukarya

• cell type: eukaryotic

• number of cells: multicellular

• nutrition: all are autotrophs, some are also heterotrophs

• cell wall: cellulose

• reproduction: some asexual, some sexual, some do both

types of plants

• asexual reproduction

  • non-vascular

  • seedless vascular

• sexual reproduction

  • gymnosperms

  • angiosperms

non-vascular plants

• no vascular tissue

• transports nutrients and water with diffusion and osmosis

• hold water like sponge

• no roots (instead root like structure called rhizoids)

• reproduce by sending out spores from stalks

• mosses and mosslike

seedless vascular plant

• first plant life on land

• have vascular tissue that allow them to grow tall

• reproduce by sending out spores into the air that land in soil

• ferns and relatives

gymnosperms

• reproduce sexually using seeds that are on the surface of cones

• seeds allow them to survive long winters without water

• male cones sends thousand of grains of pollen that find female cones

• female cones remain of tree until their is enough moisture to mature

• cone bearing trees (conifers) and most large trees

angiosperms

• plants that grow and develop seeds enclosed in fruit

• divided into two types

  • monocots (one seed leaf)

  • dicots (two seed leaves)

• use animals to directly transport seeds/pollen (some still use indirect methods)

• flowering plants and deciduous trees

characteristics of protists

• not a fungus, plant or animal

• domain: eukarya

• cell type: eukaryotic

• number of cells: most are unicellular, some multicellular

• nutrition: autotrophs and heterotrophs

• cell wall: cellulose in some, sometimes no cell wall

• reproduction: asexual and sexual

animal-like protists

• ex: amoeba, ciliates, sporozoans, and flagellates

• characteristics

  • animal like because they consume other organisms for food

  • some species are parasites

• protozoans: ingest materials from their surroundings

flagellates

• heterotrophic

• possess 1 or more flagella (whip like tail)

• some live in mutualistic relationship

• ex: termites feed on wood but can’t breakdown cellulose

  • trichonympha live in termite intestines and produce enzymes to breakdown the cellulose

amoebas

• no cell wall or steady body shape

• move and feed using pseudopods

  • temporary cytoplasmic extensions

• can be parasitic

ciliates

• heterotrophic

• covered with cilia

  • move back and forth to move organisms

• all aquatic

sporozoans

• all parasites

• live in and feed on blood of humans and other animals

• asexual reproduction by mitosis

• sexual reproduction by forming spores

• genus plasmodium cause malaria in humans

  • transmitted between mosquitoes and humans

fungus-like protists

• ex: slime moulds and water moulds

• characteristics

  • fungus like because they absorb nutrients from living/dead organisms

slime moulds

• streaming blob that functions like amoeba

  • engulfs particles of food through cytoplasm extensions

• reproduce with spores like fungi

water mould

• live in water/moist laces on decaying matter

• release digestive enzymes on host tissue and absorb the nutrients

plant-like protists

• ex: euglenoids, diatoms, and dinoflagellates

• characteristics

  • plant like because most make their own food by photosynthesis

  • have chlorophyll

• all aquatic

euglenoid

• have plant and animal like characteristics

• swim using flagella

• have an eyespot

  • allows them to find light

  • can’t “see” through eyespot

why we care about viruses

• prevention of disease

• vaccination

• genetic engineering

viruses aren’t alive

• don’t metabolize

• can’t replicate on their own

• present as parasites in all organisms

characteristics of living things

• organized

• reproduction

• homeostasis

• react to environment

• growth and development

• metabolism

• evolution

virus morphology

• very small, smaller than bacteria and violet visible light

• consist of:

  • DNA (or RNA) embedded in a protein coat (capsid)

  • some viruses have an envelope surrounding the capsid

envelope

• lipid membrane that is studded with proteins

• spikes are responsible for attaching the virus to the to-be-infected cell