Bio Lab II Test #1

Taxonomy

Branch of science that classifies biological organisms based on shared characteristics.

Eukaryotes

• Have membrane bound organelles

• Multicelluloar

• 10x larger than prokaryotes

• chromosomes

• complex flagellum that whip back and forht

Prokaryotes

• single celled

• circular DNA

• no membrane bound organelles

• no nucleus

• circular DNA

• Singular flagella

• Dif forms of metabolic activity

Archaebacteria

Prokaryotes that were classified as bacteria but have genes and metabolic pathways similar to eukaryotes. they are found in extreme climates. they use organic compounds for energy. they play a role in carbon and nitrogen cycles.

What are the levels of life?

Life

domain

kingdon

phylum

class

order

family

genus

species

Describe kingdom bacteria

5×10^ 30 bacteria on earth. described based on morphology, biochemistry, and metabolism. Live in symbiotic or parasitic relationships with plants and animals. They live in soil, water, acidic offsprings, and radioactive waste. They are found in the gut and sin of humans. Some can be treated with antibiotics.

Botulism

• clostridium botulinum

• lives in improperly prepared food

• contracted through ingestion or contact with a wound.

• can be fatal

What type of feeders are bacteria?

• Heterotrophic (gets energy from organic compounds made by their host. also decomposers who feed on dead organic matter and release nutrients) .

• Autotrophic (Derive energy from photosynthesis).

What are the 3 shapes of eubacteria (found in everyday life)?

Bacillus (Rod shaped)

Cocci (spherical shaped)

Spirillum (Spiral shaped)

What type of reproduction does bacteria do?

Asexually reproduce through binary fision.

• Attachment of chromosomes

to plasma membrane

• Enlargement of cell volume

and size

• DNA replication

• Inward growth of the cell wall

and plasma membrane

• Pulling apart of

chromosomes

• Distribution of the cytoplasm

• Division of daughter cells

Gram stain

A way of classification of bacteria based on structural

and chemical composition of the bacterial cell wall

• Gram-positive – bacteria that have thick cell wall and retain

purple dye; are more susceptible to antibiotics

Streptococcus, Micrococcus

• Gram-negative – bacteria that have thin wall and do not

retain dye; are less susceptible to antibiotics

Escherichia coli, Serratia

Bacterial colony morphology

The physical appearance of the bacteria on the agar surface.

Nitrogen fixation

a proceses in which bacteria and cyanobacteria transform atmospheric Nitrogen into other Nitrogenous compounds which plants use as nutrients. They use an enzyme called Nitrogenase.

Rhizobium

A bacteria which colonizes plant cells of roots and legumes and can fix nitrogen. its a symbiotic relationship with the plants.

Sensitivity plate

Determines which antibiotic are most effective against certain bacteria. If theres a bigger clear ring around the bacteria, means the antibiotic was more effective.

Phylum Cyanobacteria

• They are photosynthetic and can be free living or symbiotic.

• Not related to other algaes

• Not eukaryotes

• Have different pigments

Oscillatoria

• fillamntus in nature

• under low power you see strands

• Lungs of a ladder

Merismopedia

• makes a geometric shape

Gloeocapsa

• Very small, circular things

Nostoc and Anabena

Exists in chains

Kingdom Protista

• Encompasses all Eukaryotes that aren’t fungi, animals, and plants. its very diverse.

• Microscopic

• Live in moist places

• Simple level of organization

• Divided in algae, protozoa, and slime mold.

• Thought to have given rise to the animal kingdom.

Algae

• Informal grouping of autotrophic protists based on their type of photopigment, energy storage, and composition of cell walls.

• consist of 10 protists that are mainly photosynthetic.

• Have more than one common ancestor

• Help with oxygen production

• Help control pollution

• Major food source in the ecosystem

• Unicellular and multicellular

Different types of cellular organization of algae: (3)

• Unicellular

• Fillamentuos (chains of cells attached to each other: branched or unbranched).

• Colonial (attached to each other, not in filamentous manner (they are in circular or other 3D things).

Phylum chlorophyta (green algae)

• in fresh and salt water

• protists, not plants.

• Called chlorophytes

• There are unicellular, filamentous, and colonial.

Chlamydomonas

• Found in soil, lakes, and ditches.

• Has large chloroplasts

• Produce and store starch

• have both sexual and asexual reproduction.

• Sexual - under harsh or unfavorable

  conditions

  • Covers with a thick, resistant wall- zygospore

  • Undergoes meiosis to produce 4 haploid spores

• asexual - most common via mitosis, haploid

Spirogyra

• fillamentuos green algae

• slippery

• grows in streams of fresh water

• reproduces by conjugation (through cross bridges)

Cladophora

• fillamentuos green algae

• coarser

• reproduces by alteration of generation

Volvox

• Lots of spherical cells

• synchronized beating of flagella spins colony through the water

• parent colonies have asexual daughter colonies

• can also reproduce sexually

Phylum Phaeophyta (brown algae)

• marine, multicellular algae

• Brown

• important for food and habitat

• microscopic and big (theres a range)

Phylum Rhodophyta (red algae)

• Warm, marine enviornment

• red

• attached or free floating

• could be food

Phylum Heterokontophyta (Diatoms)

• Unicellular algae

• golden brown

• photosynthetic

• food source

• hard cell wall made of silicon dioxide (glass)

• geometric shape (have a transparent look).

Phylum Dinoflagellates

• Unicellular

• weird shaped cellulose plates

• have 2 flagella perpendicular to each other

• autotrophic and heterotrophic.

• oval shaped. lots of chloroplasts.

• They aren’t a plant or an animal

Phylum Euglenozoa (Euglena)

• Fresh water

• unicellular

• no cell wall

• 2 flagella

• Can be sutotrophic, heterotrophic, and saprophytic. (oval shaped. lots of chloroplasts

• Not plant or animal

Protozoa

• First animal

• Heterotrophic eukaryotes

• Energy from organic molecules made by organisms

• have vacuoles and contractile vacuoles

• some have flagella, some have cilia, and some have pseudopods (all different ways of movement).

Phylum amoebozoa (Amoeba)

• marine and freshwater environment

• have pseudopods (finger like things that help with moving and food gathering)

• Intake food through vacuoles (phagocytosis)

• no cell wall or chloroplasts

Phylum Sarcomastigophora (flagellates)

• At least one flaggelum

• free living or parasitic

• Tryponsoma- Tropical pathogen that causes African sleeping sickness. spread thofuth biting insects. fever, headache, joint pain.

Phylum Cilliophora (Ciliates)

• Lots of cillia

• have 2 types of nuclie

• Paramecium: free living, in fresh water. reproduces sexually and asexually through conjugation.

  

• Vorticella: Has contractile stalks to attach to a substrate. cell body with cilia. filter dees through cilia beating rapidly to capture food.

  

Plasmodium

• No cilia, flagellates, or pseudopods.

• unicellular

• parasitic

• causes malaria through mosquitos

• look for abnormal shape in blood cell

Domain Eukarya: Kingdom fungi

• Eukarytic

• Unicellular and multicellular

• Cell wall made of Chitin

• heterotrophic (specifically absorptive—they secret enzymes and feed on the organic material that they grow on).

• Have varied uses (food poison, antibiotics, disease, recycle nutrients, kill crops).

Hypha

• Basic structure of fungi. They arise from spores. A group of them are called mycelium.

• Secret enzymes for extracellular digestion

• absorb digested nutrients (absorptive heterotrophs)

Two types of fungi feeders:

1) Saprophytes- Get food from organic, dead matter.

2) Parasites- feed off of living organisms.

How do fungi reproduce?

• Sexually through meiosis, vegetative growth, nuclear fusion, genetic recombination

• Asexually through spores (mitotic division of haploid vegetative cells), budding (mitosis followed by uneven distribution of the cytoplasm (which happens in yeast)), and fragmentation (breaking of the organism into one or more pieces)

How are fungi classified?

Based on their sexual structures

What are the 4 phyla of fungi?

• Chytridiamycota

• zygomycota

• ascomycota

• basidiomycota

Phylum chitridiomycota (Chytrids)

• mainly aquatic

• Motile spore with flagella

• grown in freshwater algae

Phylum zygomycota

• Most common genus is Rhizopus (bread mold).

• appears dark because of thousands of black sporangia

• strains grow towards each other and form gamentangia (reproductive structure).

Phylum ascomycota

• Sac fungi

• Includes yeast, mold, and morels.

• They have microscopic sac-shaped reproductive structures (ascus).

• They reproduce asexually by forming spores.

• used for penicillin, food, and yeast.

• Sacchaaromytes are yeast.

• Peziza and Aspergillus are other types

Phylum basidiomycota

• Club fungi

• mushrooms

• Basidia are external club shaped structures on the surface of gills (hypha) that are sights of sexual reproduction

Lichens

Usually bright colored, live on a variety of hard substances in nature. They are made of ascomycetes and live symbiotically with photosynthetic algae and cyanobacteria. They reproduce asexually.

Stages of the cell cycle

INTERPHASE: G1- Cell growth

S- DNA replication

G2- Prep for mitosis

M PHASE: Mitosis

takes 10-30 hours in total

How does DNA arrange into chromosomes?

Before mitosis, DNA condenses into chromosomes. They start as chromatin and condense into X-shaped chromosome with two telomeres (arms) and a centromere (holds structure together).

Homologus chromosomes and sister chromatids

Homologus chromosomes are near each other in the cell.

Sister chromatids are the identical copies of a single chromosome that are held together by a centromere

What is mitosis?

It is DNA replication that results in 2 identical daughter cells.

10% of the cell cycle time is spent on it.

Stages of Mitosis:

Interphase

prophase

prometaphase

metaphase

anaphase

telophase

(cytokenesis)

Interphase

G1, S, G2

Prophase

Loose DNA condense into chromosomes

Prometaphase

Nucleur membrane disintegrates and spindles connect to the chromosomes.

Metaphase

Chromosomes align in the middle

Anaphase

Chromosomes seperate into chromatids and migrate to polls.

Telophase and cytokinesis

Cleavage furrow (plants). spindles disintegrated. New nuclear membrane forms. cell splits into two.

Chromosome #

(n)- haploid number of chromosomes (23 for humans)

(2n)- diploid number of chromosomes. All somatic cells have 2x number of haploid cells.

Meiosis

starts with 1 (2n) cells and ends in 4 (n) cells. It does two rounds of cell division.

There is genetic recombination (crossing over) during prophase I.

Meiosis I is Division of homologous chromosomes (2n)—> 2n and 2n.

Meisis II is Division of sister chromatids (2n)—> n and n

Gametiogenisis

Process of meiosis that produces haploid daughter cells that turn into gametes.

spermatogenesis is forming sperm.

Oogenisis is forming eggs.

Kingdom Animalia

Multicellular, Eukaryotic, heterotrophic.

They are classified by body symmetry, tissue organization, type of body cavity, and structure+function of organs.

3 types of body symmetry:

Asymetrical- however you cut it, you get different cross sections

bilateral symmatry- When cut down the middle, you get identical right and left

radial symmetry- However you cut, you get identical cross sections

Phylum Porifera

• They are asymmetrical sponges.

• No distinct tissues or organs'

• saclike body consists of two layers

• have pores on outside that allows water to move in

• internal cavity is lined with food filtering choanocytes. Choanocytes have flagella coming out to keep water flowing and helps digest as well.

Phylum porifera: Grantia

• one of simplest sponges

• filter feeder

• many have color bc of symbiotic algae that live in them.

• have a folded wall with canals lined with choanocytes

Phylum Porifera: Euplectella

Have spicules

• Crystal-like skeletal structure

• Shrimp species can live in it

Called glass sponge

Phylum Cnidaria (4 classes)

• They are marine carnivores with radial symmetry

• Cubozoa (boxed jellyfish)

• Hydrozoa (hydra)

• Anthozoa (coral)

• Scyphozoa (moon jellyfish)

2 body patterns of cnidaria

• Polyp form (tentacles facing up). Mouth surrounded by tentacles.

• Medusa form (tentacles facing down). mouth facing down surrounded by tentacles.

Class Hydrozoa

Hydra

• predominantly in polyp stage

• live in freshwater ponds

Obelia

• has both polyp and Medusa stage

Class Scyphozoa

• known as jellyfish

• medusa stage is main life cycle

• Gastrovascular cavity is divided into 4 pouches (radial symmetry)

Class anthozoa

Metridium (anemones)

• Attach to a substrate but can slide along it

• Reproduce by fragmentation (asexual)

• Gastrovascular cavity is partitioned by a thin septa

Corals

• Smaller than anemones

• Secrete hard skeleton composed of calcium carbonate (CaCO3)

• Small depression are formed where polyps used to be

Class Cubozoa

Box jellyfish. Medusa

Phylum Platyhelminthes

Flatworms.

• Live in a wide range of habitats

• Marine, freshwater, terrestrial and parasitic

• Have more complex morphology

• Have three embryonic germ layers: ectoderm, endoderm and

mesoderm

• Have organs composed of interdependent tissue

• Bilateral symmetry

• Acoelomate- no internal cavity, mesoderm is a solid mass of tissue

Phylum Nematoda

Round worms.

• Live in a wide range of habitats

• Marine, freshwater, terrestrial and parasitic

• Have more complex morphology

• Have three embryonic germ layers: ectoderm, endoderm and

mesoderm

• Have organs composed of interdependent tissue

• Bilateral symmetry

• Roundworms

• Pseudocoelomates- have body cavity with internal organs in it

Phylum Platyhelminthes continued/specific

• free living

• gastrovascular cavity with one opening (sac body)

• Acoelomate with bilateral symmetry

• Nervous system more advanced that that of Cnidarians

• Consists of Class Turbellaria, Class Trematode, and Class Cestoda

Class Turbellaria

Can live in freshwater, saltwater and moist terrestrial

environments

• Are hermaphroditic- each worm has both male and female

sex organs

• Feed on small animals

• Dugesia also called planaria

• Eyespots- lateral sensory organs on the head

• Pharynx- intaken food travels along into gastrovascular cavity

• External digestion in the gastrovascular cavity followed by

intracellular digestion of small particles

• Mesoderm- mass of cells between ectoderm and endoderm

• Can regenerate

Class Trematoda

Are parasites a few mm long

• Also called fluke

• Infect hosts and can live inside the host

or on the surface of the host

• Lack epidermis and are covered by

apicuticle (proteins and lipids)

• Helps respiration and absorption of

nutrients

• Have two adhesive oral suckers on the

ventral surface

Class Cestoda

• Tapeworms

• Are endoparasites of the gut of vertebrates

• Lack mouth and digestive tract

• Scolex- anterior end that attaches to host’s

intestinal wall

• Proglottids- segments of the body that grow

• Can self-fertilize or cross-fertilize

• Can be up to 10m in infected humans

Phylum Nematoda

• Roundworms.

• Many cause diseases in humans, animals or plants

• Elephantiasis caused by Filaria resulting in swelling of arms or legs caused by clogging of the lymphatic system

• Loa loa- parasitic nematode that is the eye worm

• Are covered with a flexible cuticle that resists digestive enzymes but is permeable to water, ions and dissolved gasses

• Have pseudocoelom with a digestive tract and internal organs

suspended in the cavity