DIVERSITY OF FORM & FUNCTION EXAM 1

Classification

-Similar features

-Animal/Vegetable/Mineral

-Micoscopes

--micoorganisms

-Kingdoms

--bacteria(prokaryotes)

--Animals, plants, fungi, single-celled eukaryotes

-Based on morphological features

Genetics

-We resemble our relative bc we share many alleles(specific versions of genes)

--Most accurate measure of relatedness is how similar genomes are

DNA

material of inheritance, common to all organisms

rRNA

-First widely compared sequences

--Life depends on protein synthesis

--Ribosomes must function to make proteins

--Genes for ribosomal RNA evolve very slowly

Prokaryotes

-Bacteria

-Archaea

--Neither have a nucleus

--Archaea are more closely related to eukaryotes

Membrane enclosed nucleus is present in?

Eukarya

Membrane enclosed nucleus is absent in?

Bacteria and Archaea

Membrane enclosed organelles in eukarya?

Many

Membrane enclosed organelles in Archaea?

Absent

Membrane enclosed organelles in Bacteria?

Few

Peptidoglycan in cell wall in Eukarya?

Absent

Peptidoglycan in cell wall in Archaea?

Absent

Peptidoglycan in cell wall in Bacteria?

Present

Membrane lipids in Eukarya?

Ester-linked and unbranched

membrane lipids in Archaea?

Ether-linked and branched

Membrane lipids in Bacteria?

Ester linked and unbranched

Ribosomes in Eukarya?

80S

Ribosomes in Archaea and Baceria?

70S

Initiator tRNA in eukarya?

Methionine

Initiator tRNA in Archaea?

Methionine

Initiator tRNA in Bacteria?

Formylmethionine

Operons in Eukarya?

Rare

Operons in Archaea and Bacteria?

Yes

Plasmids in Eukarya?

Rare

Plasmids in Archaea and Bacteria?

Yes

Number of RNA polymerases in Eukarya?

Three

Number of RNA polymerases in Archaea and Bacteria?

One

Ribosomes sensitive to chloramphenicol and streptomycin in Eukarya and Araches?

No

Ribosomes sensitive to chloramphenicol and streptomycin in Bacteria?

Yes

Ribosomes sensitive to diphtheria toxin in Eukarya and Archaea?

Yes

Ribosomes sensitive to diphtheria toxin in Bacteria?

No

Gram Staining

Peptidoglycan in cell wall

Gram positive

cell wall take sup violet dye, dense cell wall of peptidoglycan

Gram negative

appears pink or red, very thin layer of peptidoglycan and an outer membrane.

Coccus

sphere shape

Bacillus

rod shape

Helix

spiral shape

Prokaryotes rely on what for movement of materials through cell?

Diffusion

Quorum sensing

Triggers biofilm formation

Prokaryotes reproduce by...

fission but can exchange genetic material

How do prokaryotes exchange genetic material?

Horizontal or vertical transfer

Horizontal gene transfers

complicates use of sequences to determine phylogenies

Vertical gene transfers

Generation to generation as in multicellular organisms

Metabolism/Environment in Prokaryotes

Oxygen is poisonous to some prokaryotes

--Anaerobes

Others require oxygen

--Obligate aerobes

Others can use either!

--Facultative anaerobes

Cyanobacteria in nutrition

-Photosynthesis

--Photoautotrophs

---Converting Earth's atmosphere to aerobic in ancient past

Photoheterotrophs

Harvest energy from light but rely on sugars made by other organisms

Chemoheterotrops

feed on other animals

Decomposers

break down dead bodies

Nitrogen fixers

convert N2 from atmosphere to NH3

Nitrifying bacteria

NH3--->NO2--->NO3

Available to plants for amino acid, nucleic acid synthesis

Denitrifying

convert organic nitrogen to N2

Beneficial prokaryotes in health and disease

rumen flora of cattle have cellulase- eat grass

--Lehume roots house nitrogen fixing bacteria

Harmful pathogens of prokaryotes

Anthrax in sheep, cattle, and sometimes humans

--Agrobacterium in plants:crown galls

Pathogens (prokaryotes)

-Only a tiny percentage of prokaryotes are pathogens

How prokaryotes cause disease

Invade the body, evade immune system, multiple, produce toxins

Endotoxins (host exposed when bacteria lyse)

Fever, vomiting, diarrhea

Exotoxins (related by living bacteria)

Highly poisonous or fatal

Features of eukaryotes

Organized nucleus

-Linear chromosomes, membrane-bound

Organelles

-Mitochondira

-Chloroplasts

-Digestive vacuoles

Organelles

Membranes associated with specialized fucntions

Vesicles

Move materials in and out of cell

Cytoskeleton

Movement relies on this

-Predation

-Change shape

-Increased size

Chromosomes and Sex (eukaryotes)

-Linear DNA molecules

-All have a sexual life

-Meiosis

Eukaryotes include..

Plants, Animals, Fungi (ALL MULTI CELLULAR)

-Protists (usually single-celled)

Multicellular organisms after cell division...

cells stay together

-provides opportunity for specialization

-Greater size

Superkingdoms

Plants

Animals

Protists

-Single celled

-Diverse, polyphyletic

-Many niche

-Flagella, cilia, pseudopods

-can be complex

Opisthokonts

Flagellum is posterior, single

-Animals (multicellular)

-Fungi(uni or multi)

Choanoflagellates -- opisthokonts

Can be colonial

-first step toward multicellularity

Fungi -- opisthokonts

cell wall of chitin

multicellular or uni

absorptive heterotrophy

-enzymes are secreted, break down food, absorbed

-can feed on living or dead organisms

-fungicides are toxic to animal cells

--major role in decomposition of dead organisms

Fungi can be beneficial or harmful to other organisms

fungal infections in animals

-Plant pathogens: rusts, smuts

-Symbiosis: mycorrhizal dungi-allo trees to take up more minerals from sol

-Lichens: fungus + green algae

Amboebozoans

use pseudopods for motility

-aquatic (fresh water)

-moves via pseudopods

-eats via phagocytosis

-Predator scavenger, or parasite

Physarum -- amboebozoans

plasmodial slime mold

-terrestrial (forests)

-dispese, then aggregate to form fruiting bodies

-ingest by endocytosis

-move my cytoplasmic streaming

Dictyostelium -- amboebozoans

cellular slime mold

-Amoeba-like single sells aggregate into slug when dry or starved

-are retained, form spores

Rhizaria

unicellular, aquatic, long pseudopods, marine

Foraminiferans -- rhizaria

external shells of calcium carbonate

-source of limestone

-psedudopods ensnare plankton

Radiolarians -- rhizaria

glassy endoskeletons

-include some of the largest unicellular eukaryotes

-can have photosynthetic endosymbionts--dinoflagellates

Archaeplastids

land plants (multicellular)

Red algae -- archaeplastids

Marine

photosynthetic

chlorophyll a, phycoerythrin

Green algae -- archaeplastids

chlorophyll a, b

-uni or multi cellular

--multicellular:

volvox - spheres of flagellated cells

sea lettuce - marine

Stramenopiles

have unequal flagella

Diatoms -- stramenopiles

silica in cell walls - upper and lower like a petri dish

-aquatic: fresh and salt

-photosynthetic : storage products oils

- Diatomaceous earth : filtration

Brown algae - stramenopiles

can be multicellular

-sea palms, giant kelp

-phtosuntethic

-chlorophyll a,c + brown pigments

--source of emulsifiers of ice cream

Alveolates

sacs under cell membrane

single celled

paramecium --alveolates

ciliate

body covered with cilia - motility

fresh water

sex : equal exchange of nuclei

dinoflagellates -- alveolates

red tides

plasmodium -- alveolates

apicomplexans

parasite causing malaria

-life cycle in mosquitoes, human blood

--none functional chloroplasts

Excavates

unicellular, often lacking mitochondria, named surface groove

giardia --excavates

diplomonad

many flagella

lacks mitochondria

fresh water - parasite causing giardiasis

Euglena -- excavates

a euglenid

-photosynthetic

-if in the dark, eats!

--anteriror flagellum

Trypanosome -- excavates

kinetoplastid

-parasite causing sleeping sickness

Endosymbiosis

Green algae, land plants: chloroplast (cp) from cyanobacterium endosymbiont

- Enclosed by 2 membranes: one from cyanobacterium, one from host cell

• Serial endosymbiosis: more than 2 membranes around cp

- Brown algae, diatoms, dinoflagellates: 4 membranes Cp derived from red algae endosymbiont:

inner 2 membranes from algal chloroplast next out from cell membrane of red alga outermost from host

- Euglenids: cp from green algal endosymbiont

Viruses

composed of protein coated DNA or RNA encoding small number of proteins

Are viruses alive?

Acellular

Mutate

Evolve

Interact with other organisms

Derived from living organisms

Virus Classification

Based on nucleic acid type

-RNA or DNA

Positive sense RNA viruses

genome is also template for translation

-rhinovirus, polio, plant diseases, zika

Negative sense RNA viruses

Upon infection, viral encoded ran-dependent ran polymerase makes complimentary strand

-template for translation

-rabies, measles, mumps, ebola ---In terms of virus genomes, "negative sense" means that a single-stranded nucleic acid molecule has the opposite sequence to messenger RNA (mRNA) and so cannot be translated into protein until it has been copied

RNA retrovirus

protein component includes reverse transcriptase-->DNA

-proviral DNA is integrated into host's genome

-Specific to vertebrate animals

-HIV

DNA viruses

smallpox, herpes, bacteriphasge

Ebolavirus

Genome encodes 7 genes

-L gene

Converts viral RNA into template for translation

-Virsus multiples-spreads in host and can infect new hosts

--Interferes with immune response, and disrupts vascular endothelial cells:hemorrhage

What is an animal?

Multicellular

-Cells adhere after biotic division

-Cells communicate with each other

Heterotrophic: eat other organisms

Internal Digestion

Motility

-Muscles, nerves, skeletons

Animal Diversity

Monophyletic

-common ancestor thought to resemble choanoflagellates

-Earliest and simplest animals are marine