BIO 181 exam 3 Dr. Paciulli

Taxon

Group designated at any level hierarchy

phylogeny

Evolutionary history of species or group

Clade

group of evolutionary ancestors & descendants of common ancestor

Sister clades

share an immediate common ancestors; each other's closest relatives

cladogram

diagram showing evolutionary relationships among organisms

phylogenetic trees

based on homology (similar in features due to common environmental pressures)

ancestral trait

in ancestor of group; may be retained or changed in descendants

derived trait

differs from ancestral form; evolutionary novelty

synapomorphy

derived traits

plesiomorphies

ancestral trait state

symplesiomorphies

shared ancestral trait states

Michael Urey

spark-> reduced atm->condenser->liquid with amino acids

first cells formed

3.5 BYA and resemble prokaryotes

stromatolite

mats of cynabacterial cells that trap mineral deposits

Great Oxygen Event

2.3 BYA; cyanobacteria; began producing oxygen by photosynthesis and it began to accumulate in the atm. The O2 reacted with the UV radiation to form O3 (Ozone)

Three monophyletic domains

BAE

Eukaryotes formed

1.5 BYA > 2BY after bacteria

How do we classify all living organisms?

1. life cycles

2. extraembryotic membranes

3. excretory product

4. temperature regulation

5. skull types

Haploid

single set of unpaired chromosomes

Diploid

two complete sets of chromosomes (one from each parent)

Gametes

mature haploid cells (male or female). fuse with other haploid cells to form zygote

Gametophyte

sexual phase in alternation of generation life cycle

meiosis

single cell divides twice (4 daughter cells with 1/2 chromosomes of parent)

mitosis

nuclear division to produce 2 identical daughter cells

spore

one celled reproductive unit. asexual

sporophyte

asexual, diploid phase that produces spores

endothermic

produces own heat

exothermic

relies on heat from environment

homeothermic

keeps body temp constant

heterothermic

allows body tempt to fluctuate

ammonia

fish

urea

mammals

uric acid

birds

amniotes

have sac containing fluid to protect embryo

anapsid skull

no holes

synapsid skull

1 hole

diapsid skull

2 holes

Archea and Bacteria are..?

microbes; Almost all are unicellular but very complex

do prokaryotes have a cell wall, a nucleus, and organelles?

Prokaryotes have a cell wall but not a nucleus or organelles

Prokaryotes can live in diverse habitats because they are..?

thermophilic and halophilic

teaspoon of soil has how many microbes/prokaryotes?

billions

Another name for Bacteria and Archea is?

decomposers

In aquatic environments prokaryotes are a part of...?

plankton

what are the 3 main shapes of prokaryotes?

spherical, rod-shaped, spiral

do prokaryotes move? and if so how and when?

prokaryotes only move towards or away from stimuli via their taxis

what type of membranes do different types of prokaryotes have?

Aerobic prokaryotes: respiratory membrane

photosynthetic prokaryotes: thylakoid membrane

How does prokaryotic DNA differ from eukaryotic?

Prokaryotes have a long of DNA instead of a double helix, and it is 0.001x smaller than that of a eukaryotes

what is the DNA molecule called in prokaryotes that can replicate independently of chromosomes?

plasmids

Domain Eukarya contains

protists, fungi, plants, animals

how much larger are protists than bacteria?

10x

protists are divided into

organelles

what is the most divers of the eukarya domain?

protists

protists are usually...?

aquatic

why does diversity in protists exist?

endosymbiosis

what is endosymbiosis?

A theory that unicellular organisms engulfed other cells which became organelles: chloroplasts, mitochondria

how do protists reproduce?

sexually and asexually

why are protists important?

disease, decomposers, and plankton

how do protists eat?

absorptive or ingestive

how do protists move?

Amoeboid = crawls via pseudopodia

flagellated = swims via flagella

ciliated = swims via cilia

what are the two growth forms of fungi?

single celled: yeast

multicellular filamentous structures: mycelia

what makes up multicellular filamentous structures?

hyphae that have cells walls and are mostly chitin

how much hyphae can grow a day?

a kilometer

how do fungi eat?

sabrobes: absorb nutrients from nonliving organisms (decomposers)

parasites: absorb nutrients from cells of living host

what is a haustoria?

a slender projection from the root of a parasitic plant, such as a dodder, or from the hyphae of a parasitic fungus, enabling the parasite to penetrate the tissues of its host and absorb nutrients from it.

mycorrhizae

symbiotic relationship between plants and fungi. fungi colonize the root system of the plant, increasing nutrient and water absorption while the plant provides carbohydrates for the fungi

homology vs. homoplasy?

Homology is the product of divergent evolution. two species were once the same species at the point where they have a most recent common ancestor. The species, even though they diverged at that point, still retain some of the characteristics of the common ancestor.

Homoplasy is the product of convergent evolution. Similar traits evolved independently of each other and are not found in the common ancestor of the two species being examined.

parsimony

choose the simplest scientific explanation that fits the evidence. The simplest of competing explanations is the most likely to be correct.

what are the differences between hyphae, mycorrhizae, and mycelium

mycorrhizae fungi organize the roots of plants using hyphae. hyphae make up the mycelium that make the body of the fungi

why are fungi important to plants?

increases the surface area of the plants roots and makes the roots closer to water/nutrients and more efficient at obtaining it.

what percentage of plants depend on fungi?

85% of plants would not survive without fungi

xylem

transport water from roots to shoot and leaves, but it also transports some nutrients.

phloem

the vascular tissue in plants that conducts sugars and other metabolic products downward from the leaves.

pteridophytes

seedless vascular plants have vascular tissue but do not make seeds

bryophytes

nonvascular plants: no vascular tissue to conduct water or provide support. Only near/in water

Gymnosperms

seed plants have vascular tissue and make seeds (conifers)

Angiosperms

flowering plants

what are animals body plans based on?

1. # of tissue types in embryo

2. type of body symmetry

3. degree of cephalization

4. presence of absence of a fluid-filled cavity

5. the way early development proceeds

compare and contrast perifera and sponges

Animals that have tissue

eumetazoans

diploblasts

two sprouts/germ layers (truly-among-animals)

ectoderm

outside skin

endoderm

inside skin

triploblasts

three germ layers

mesoderm

area between the inside and outside skin.

area between ecto- and endo-derm

diploblasts are typically

cnidaria/jellyfish

adult echinoderms

starfish etc with radial symmetry.

coelom

fluid-filled space separating digest tracts from outer body wall coelom that protects internal organs

the coelom derives from the

mesoderm

do all mesoderm have a coelom?

no, the coelom is derived from the mesoderm, but not all mesoderm have coelom

sponges have

no tissue; are called parazoans

how do prokaryotes reproduce?

divide by binary fission every 1-3 hours. sometimes form endosperms

ascomycetes

spores are produced in asci (flat/cup)

basidiomycetes

spores on bodies grown from basidia (club/tube)

cyanobacteria

first microbes to produce oxygen by photosynthesis