Bio 1101 final

Altruism

an action that reduces an individuals own fitness while increasing the fitness of another

inclusive fitness

direct fitness (offspring) and equivalents gained through support (kin)

Nash equilibrium

-the best response given another's response

-always play the selfish card

-unstable

evolutionarily Stable strategy

-a strategy that cannot be invaded by a rare mutant using an alternative strategy

-special case of Nash equilibrium

cooperatively breeding

-some members forego reproduction

-devote energies toward rearing of young of others

eusoical

-individuals cooperate in the care of young

-reproductive division of labor

2 hypotheses of why altruism happens

1. selection at the level of the family (kin selection)

2. reciprocity

kin selection

-acting on individuals related through recent, common descent

-depends of relatedness (percentages of shared allels)

hamilton's rule

fitness=w-c+rb

act altruistically if c

reciprocal altruism

altruism is rewarded with altruism, defection punished by defection

cost v benefit of helping

cost= fitness when not helping - fitness when helping

benefit= fitness when helped- fitness when not helped

genera

earliest classification system which grouped animals and plants into units

taxon

organisms at a particular level in a classification system

scientific names

first part is genus, second is specific epithet (species)

Hierarchical Classification

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

John Ray

first definition of a species

all the individuals that belong to it can breed with one another and produce fertile offspring

biological species concept

-defines species as groups that are reproductively isolated

-doesn't work for asexual reproductive organisms

phylogeny

the evolutionary history of an organism and its relationship to other species

cladistics

phylogeny according to similarities derived from a common ancestor

clade

a group of organisms that share a derived character

6 kingdoms

Animalia, Plantae, Fungi, Protista, Archea, Bacteria

3 domains

Archaea, Bacteria, Eukarya

which prokaryotic kingdom is closer to eukaryotes

archaea

Archaean characteristics

-unique cell walls, lipids, and rRNA sequences

-some genes have introns

-found in extreme environments

When did eukaryotes appear

1.5 billion years ago

endosymbiosis

bacteria entering an early eukaryotic cell created a mitochondria and chloroplasts

when did prokaryotes first appear

3.7 billion years ago

evolutionary tree

a diagram that reflects evolutionary relationships among groups of organisms based on similarities in DNA, physical features, biochemical characteristics, or a combo

node

marks when an ancestral group split into two separate lineages

fungi includes

yeasts, molds, mushrooms

who were the first terrestrial colonists

algae-like plants

waxy cuticle purpose

retain moisture

gymnosperms

-first plants to evolve pollen and seeds

-removed dependence on water for fertilization

angiosperms

-first plants to evolve flowers

-most dominant and diverse group of plants

order of main events

1. 650 mya life in water

2. 540 mya Cambrian explosion

3. 480 mya algae-like plants make it to land

4. 460 mya fungi make it to land

5. plants on land

6. 360 mya end of the Devonian period

7. 400 mya animals on land

8. 365 mya amphibians on land

9. 230 mya reptiles most common

10. dinosaur age

how many mass extinctions have there been?

5

causes of mass extinction (4)

climate change, massive volcanic eruptions, changes in composition of marine and atmospheric gases, and sea level changes

Cretaceous extinction event

-65 mya

-wiped out 3/4 of plant and animal species (including non-avian dinos)

-massive comet/asteroid in Gulf of Mexico

adaptive radiation

-a group of organisms expand to take on new ecological roles and form new species and higher taxonomic groups

-happen after mass extinctions

example of adaptive radiation

mammals diversifying after extinction of dinosaurs

ratio of human cells to microbial cells

1:1

affects of the human microbiome

-gut health

-brains

-body odor

-risk of infection

-attractiveness (to people and mosquitos)

who was the first to branch off from the shared ancestor

bacteria

prokaryotes

-single-celled organisms

-single loop of DNA

-able to reproduce rapidly

prokaryote basic structural plan

-protective cell wall

-some have a capsule around the cell wall, and/or pili, and/or a flagella

what do capsules do

help bacteria to evade the immune system

what do pili do

-help organisms link together and attach to surfaces

what does a flagella do

help propel bacteria through liquid

thermophiles and halophiles

- archaeans

-heat and salt lovers

quorum sensing

-a system of cell-to-cell communication

-allows them to sense and respond to other bacteria in accordance with the density of the pop.

binary fission

-method in which prokaryotes reproduce

-asexual reproduction

-splitting of DNA

prokaryotic forms of reproduction

binary fission, horizontal gene transfer, bacterial conjugation, sporulation

horizontal gene transfer

-indirect transfer of genes by capturing bits from the environment and incorporating them into their own genes

bacterial conjugation

-direct transfer of genes between bacteria

sporulation

-formation of thick-walled dormant structures (spores)

-can survive harsh temps

-allow microbes to survive until conditions are favorable to reproduce

metabolic types

-aerobes (need oxygen)

-anaerobes (some are methanogens, some perform fermentation)

feeding types

chemoheterotrophs, photoheterotrophs, chemoautotrophs, photoautotrophs

nitrogen fixation

Process of converting nitrogen gas into ammonia (bacteria)

dysbiosis

when the human microbiome shifts out of balance

features of eukarya

-true nucleus

-DNA enclosed in 2 concentric layers of membranes

-organelles

Protists

-defined by exclusions

-most single-celled eukaryotes

-protozoans and algae

-flagella, cilia, pseudopodia

-many are heterotrophs

protozoans

nonphotosynthetic and motile protists

algae

photosynthetic and may/may not be motile

how to motile protists move?

-swim by flagella or cilia

-crawl by pseudopodia (false feet)

why can multicellular organisms grow large?

they can gather resources more effectively which allows for production of more surviving offspring

plants

-evolved from green algae

-multicellular autotrophs

-vascular tissue

bryophytes

-liverworts and mosses

-ancestors of first plants

-simple plants, small

-absorbed water through a wicking action

vascular tissue

a network of tubelike structures specialized for transporting fluids

-first plants with these were ancestors of ferns

ferns

-vascular tissue

-lignin

seeds

-consist of the plant embryo and stored food supply

-came from gymnosperms

fungi

-absorptive heterotrophs

-zygomycetes, ascomycetes, basidiomycetes

-protective cell wall, store food energy in the form of glycogen

zygomycetes

mold species

ascomycetes

-diverse group

-sac fungi

basidiomycetes

club fungi

truffles

-fruiting body of a type of ascomycetes

yeasts

-single-celled fungi

-produce alcohol and carbon dioxide

fungi structure

-body is a network of thin filaments

-provides large surface area to absorb nutrients

-penetrates food source

-secrete enzymes

importance of fungi

-economically (bread, wine, beer)

-gastronomically (edible mushrooms)

-medically (penicillin)

hyphae

branching fungal threads that absorb nutrients from the environment

mycelium

mass of hyphae forming the body of a fungus

fungal reproduction

both asexual and sexual

asexually through fragmentation

mycorrhizal fungi

fungi that surround plant roots and help plants obtain water and minerals

lichen

-mutualistic association between a fungus and a photosynthetic microbe

-microbe provides sugar and carbon compounds

-fungi provides lichen acid for protection

Neanderthals

-closest human relative

-humans contain some of their DNA

-humans and them interbred

-same genus as humans

animals

-multicellular ingestive heterotrophs

-first evovled 700 mya

sponges

-asymmetrical body plan

-most ancient animal lineage

body symmetry

-all animals except sponges

-radial (vertical plans across center)

-bilateral (one plane vertically in two halves)

chordates

-dorsal notochord

-dorsal nerve cord

dorsal notochord

-a flexible rod along center of the body crucial for development

-evolved into discs between vertebrae

vertebrates

all chordates with backbones

evolution of vertebrates

1. jawless fish (cartilage skeleton)

2. hinged jaws

3. replacement of cartilage to bone

Class Mammalia

-body hair, sweat glands, mammary glands

-eutherians, marsupials, monotremes

eitherians

-offspring are nourished inside the mother's body via placenta

-born in a relatively well-developed state

marsupials

-simple placenta

-offspring are born early and complete development in an external pocket

monotremes

-lay eggs

-no placenta

-platypus and several echidna

primates

-flexible shoulder and elbow joints

-5 fingers and toes

-opposable thumbs

-flat nails (not claws)

-large brains in relation to body size

hominids

-the ape family

-use of tools, capacity for symbolic language, deliberate acts of deception

-includes humans

hominins

-human branch of ape family

-one or more humanlike feature (thick tooth enamel, upright posture)

-includes neanderthals

what distinguishes hominins from hominids

being bipedal

mitochondrial-DNA inheritance

-occurs only from egg (not sperm)

-passed down virtually unchanged

-can be tracked from 1 generation to another and 1 species to another