GEN BIO 2 FINAL MASTER SET

flashards in order of modules given on canvas

Taxonomy

naming, describing, classifying

think “taxadermy” classifying, naming

Phylogeny

evolutionary history

Taxon

Group at any level within a hierarchy

What does natural selection require?

heritable phenotypic variation

Are phylogenetic trees set in stone, or hypothesis?

Hypothesis

Taxonomy should relfect phylogeny

True

Characteristics of virus

Made of capsid and genome

Smaller than cells (usually)

Replicate within cells, use cell’s resources

What is the capsid made out of, what is it’s purpose? same with genome

capsid - protein coat, determines morphology and attachment to host

genome can be rna/dna and single/double stranded it can also be linear or circular or segmented

Viral envelope

Phospholipid bilayer surrounding capsid

Only present in some viruses

Acquired from host, contains virus AND host proteins

Does every virus have an envelope?

Nope, the envelope is acquired from the host and has a mix of host proteins + viral proteins

Viral replication cycle

Bind to host cell

Genome enters cell

Genome replication and gene expression

Assembly

Exit

Lytic cycle

General replication cycle – kills host cells

Horizontal transmission

Done by virulent phages

virulent v temperate phages

Virulent only do lytic cycle, they only kill
temperate do lytic or lysogenic cycle

lysogenic cycle

Viral replication without destroying host cell

Viral genome integrates into host genome as a prophage

Vertical transmission

Done by temperate phages

ex - lambda phage

what where the first cells? What was the process of these cells coming into existence?

Prokaryotes

Heterotrophs ( ate shit in the primoridial soup for energy ), photosynthetic autotrophs ( cyano bacteria, once stuff run out within the soup, they used the sun for energy), oxygen revolution → aerobes

Main characteristic prokaryotes lack compared to eukaroyes

membrane bound organelles

within the tree of life, what falls under prokaryotes

Bacteria, archaea

function of the cell wall in prokaryotes, what is it made of?

Maintains shape, prevents bursting protects cell

Bacterial cell wall made of peptitoglycan (carb polymer)

pos v negative taxis

Pos taxis toward stimulus
neg taxis away from stimulus

Flagella

mostly in prokaryotes, but found in all 3 domains (convergent evolution) same function, diff origin

Function:

H+ pumped across plasma membrane by ETC – forms gradient H+ diffuses through motor, E from diffusion turns motor

prokaryote reproduction method + characteristics

Binary fission
asexual, rapid, low cost, not risky,

How do prokaryotes have high diversity while reproducing asexually

Rapid reproduction + mutation
Genetic recombination

genetic recombination

combining DNA from 2 sources

3 mechanisms of genetic recombination

transformation - picks up dna from enviornment

transduction - bacteriophage transfers genes from one cell to another

conjugation - pilus and F factor, F+ has F factor, can transfer part of chromosome.

Sister group to eukarya

Archea, based on RNA

Proteobacteria

think mitochondria

Endosymbiosis of alpha proteobacteria → mitochondria

Cyano bacteria

think chloroplast


Photoautotrophs – oxygenic photosynthesis → oxygen revolution, Endosymbiosis → chloroplasts

Archaeal Diversity

extremophiles – thrive in extreme conditions

Halophiles – high salt environments

Thermophiles/hyperthermophiles – hot environments

Methanogens – release methane as biproduct of metabolism, Anaerobic, often swamps/marshes

Eukaryote dervied traits

Nucleas, membrane organelles, cytoskeleton,

CC types of endosymbiosis

Serial - series of endyosymbiotic events

primary - phagocytosis of bacterium by larger cell (mitochondria, chloroplasts)

Secondary - bigger eukaryote englufs smaller eukaryote - secondary plastid

Plastid

term for chloroplast and related organelles

secondary plastid derivation

Secondary plastids derived from red or green algae via secondary endosymbiosis

Explain eukaryote diveristy

Mostly unicellular

Photoautotrophs, heterotrophs, mixotrophs – capable of photosynthesis and heterotrophy

Ancestral eukaryotic traits

Nucleus, membrane-bound organelles

Aerobic respiration

Mitochondria from primary endosymbiosis

Archaeplastida

D.T. → chloroplasts via primary endosymbiosis (cyanobacteria)

reg algae, green algea, land plants.

Participated in secondary endosymbiosis, got eaten, became secondary plastids

SAR

D.T. → Secondary endosymbiosis of red algae, *remember saR, R = red algae

3 clades = stramenopiles, alveolates, rhizarians

Ameobozoa

D.T. → lobe/tube shaped pseudopedia ex - slime mold

Ophistokont

D.T. → n/a

includes: Animals, fungi, several groups of protists such as nucleariids

Discoba

D.T → chrystilline rod in flagella,

Secondary plastids via green algae – mixotrophic

4 taxa in archaeplastida ROAP

red algae

chlorophytes

charophytes

plants

4 taxa in ophistokont

Nucleariids
fungi

choanoflagelletes

animals

Fungi sister taxa

Nucleariids

explain land life pre plants

Green slime - cyanobacteria, algae, small heterotrophs including fungi

Fungi D.T.

Absorptive heterotrophy: Secrete hydrolases – hydrolytic enzymes, Polymers → monomers externally

What do Virusus not do?

Carry out metabolic processes

Reproduce independent of host cells

Contain nucleus, cytoplasm, organelles (

2 main types of fungi body structure

multicellular and unicellular

Characteristics of multicellular fungi

Hyphae - long, branched, threadlike filament, Basic building block of fungus body

Chitinous cell wall (derived) - polysaccharide

Mycelium

Tangled mass of hyphae, feeding network, grows in and around food source

Ariel hyphae v fruiting body

Ariel hyphae, to hold spores up to the wind for dispersion, simple
fruiting body, complex, organized specilized sturcutre producing and protecting millions of spores

spore reproduction

haploid cells, made by hyphae or fruiting body, non motile, sexual/asexual

Land in moist place with food → germinate → new mycelium

Fungal sexual reproduction

Mating types, not male/female. Hyphae release and Extend towards pheromones

if diff mating types plasmogomy occurs, but stops at a heterokaryon (n+n) if same, plasmogomy occurs resulting in diploid zyogte and meiosis contnues to restore halpoid.
spores then grow into new hyphae

Fungi Asexual reproduction

Filamentous fungi – spores via mitosis

Single-celled yeast – cell division/budding

fungal diversity

Chytrids: basal fungi, flagellated spores
zygomecytes decomposers, black mold

glomeromycetes, mycorrhizae, mutualism with plant roots

Ascomycetes - most species, diverse

Basidiomycetes - mushroom puffballs bracket fungi

ecological significance of fungi

Mutualists, decomposers, parasites

fungi as mutualists

Mycorrhizae - extension of root system

Endophytes - make toxins that deter herbivores

can help break down material in gut - leaf cutter ant

Lichens- Fungus and photosynthetic microorganisms

Fungal parasites

Plants – chestnut blight, enters cracks in bark, hyphae spread throughout

Mycosis: fungal infection in animals

Examples: ringworm, athlete’s foot, systemic mycosis

Symmetry

Asymmetry - none

radial symmetry - any plane yields equal halves (pizza)

bilateral symmetry - Only 1 plane of symmetry through longitudinal axis

associated with cephilization

3 traits to compare in animal body plans

Body cavities

symmetry

embryonic germ layers

characteristics of animals

Heterotrophy - cannot make own energy

Structure + organization

• Eukaryotic, no cell walls

• Multicellular (derived but not unique)

• Extracellular matrix (derived and unique)

• hierarchical organization (tissues, organs, organ systems)

• development regulated by gene expression (hox gene)

3 germ layers

Ecto - outer layer, becomes nervous system

endo - innermost layer - digestive tube, other organs

mesoderm - muscle skeleton etc

Diplo v triplo blast

diplo only endo and ecto

triplo - has all three

can a diploblast have a body cavity

no, must have three embryonic germ layers

Def of Coelom & types

fluid filled cavity between digestive tube and body wall

aceloem , no cavity present

true celoem, cavity lined with mesoderm on both sides

psuedo ceoloem - cavity lined with mesoderm on outer surface, ecto derm on inner surface

Coelom advantages

Hyrdostatic skeleton - water baloon analogy, squeeze one end of it, the front end moves (worm skeleton)

circulation - ceoloem allows for circulatory system development

2 modes of development

Protostome

Spiral cleavage, first opening becomes the head, determinate cleavage

Dueterostome

radial cleavage, first opening becomes anus, 2nd becomes head, indeterminate cleavage

Sister taxa to animals

Choanoflagellates - flagellated unicellular eukaryotes

Cambrian explosion

first appearance of many body plans in fossil record

First evidence of hard body parts

biological arms race tirggered by predation

Eumetazoa D.T.

Tissues, symmetry

Bilateria D.T.

bilateral symmetry, triploblasty

bilateral symmetry and triploblasty makes sense together because bilateral symm implies an amial with a defined head and rear, along with paired organs due to left and right side ( eyes arms legs etc)

This kind of animals is shaped for movement thus needing a mesoderm wich holds muscles + skeleton

Nephrozoa D.T.

Ceoloem, extratory structures

Deuterostomia D.T.

Deuterstome development

Protostomia D.T.

Protostome development

Spiralia D.T.

protostome development, grouped by genetic similarities

Ecydysozoa D.T.

ecdysis: molting/shedding of outer covering

Proifera

Sponges, multicellular basal metazoans and has choanocytes: feeding cells of sponges

Cnidaria (jellyfish)

Basal eumatazoans

True tissues, radial symmetry, diploblastic

nidocytes - stinging cells

Phylum that fall under spiralia and their respective characteristics:

Platylementhies

• Flatworms ; DT= aceoloem

rotifera

• crown of cilia at anterior end ; psuedo coloemate

mollusca

• Mante, visceral mass, foot ; ceoloamte

annelids

• segmented worms

Phylum under Ecdysozoa and respective characteristics

Nematoda

• Psuedo celomate, cuticle

Arthopoda

• chitinous exoskeleton, specialized exoskeleton, joints

Phylum Echinodermata

Bilateral, caco3 endoskeleton, water vascular system,

phylum chordata

D.T.’s: Notochord - support alond dorsal surface

Nerve chord - tube of nervous tissue

pharyngeal slits - folds/openings in throat

post anal tail

one hox cluster (basal chordates)

Vertebrates

D.T.: Bone/cartilage veterbrae that replaces notochord, >2 hox clusters - more complex body plan

Gnathostomes

hinged jaw, bony skeleton, 4 hox clusters

osteichthyes

lung/swim bladder

Lobe fins

muscular fin for locomotion

tetrapods

4 limbs with digits

neck

fused pelvic girdle

Amniotes

Amniotic egg

• membrane and embryo - prevents dessiccation

Rib cage ventilation

mammal derived traits

Mammary glands

Give birth to live young (mostly)

Endothermy – warm-blooded

Eutherians

placental mammals – have complex placenta

Long gestation – complete embryonic development in utero

Most mammals are eutherians

D.T’s of primates

Large brain

Grasping hands/feet

Forward-facing eyes

High parental care

Complex social behavior

For monkeys and apes – fully opposable thumb

closest relative to humans

chimps

Hominin

species on human “side” of human-chimp divergence, homosapein is only living hominin

Homo sapien D.T’s

Bigger brains

Complex tools

Fully bipedal traits

Small jaws, “short” digestive system

Language, symbolic though