bio 100 exam 3 sg

phylogeny

The evolutionary history and relationships among species.

Founder effect

portion of population start new population or a population gets divided by physical barrier

thallus

vegetative body of fungus

systematics

study of the relationships and classification of organisms

saprobes

organisms that obtain nutrients by decomposing dead organic matter.

cuticle

waxy layer covering aerial portions of plants

dispersal

a few members of a species move to a new geographical area

Adaptive radiation

a single species or small group of species rapidly diversifies into many new species

microphyll

true leafs with one strand of vascular tissue

anoxic

an environment that lacks oxygen.

taxonomy

the science of naming, describing, and classifying organisms.

anaerobic

organisms that do not require oxygen.

Gene pool

the sum of all the alleles in a population

strobili

structures that contain sporangia

Gene flow

the flow of alleles in and out of a population resulting from the migration of individual or gametes

Apical meristem

tissue from which cell division for growth occurs

stomata

pores on the surface of leaves that allow gas exchange.

Bottleneck effect

event leads to a large portion of the gene pool being wiped out.

vicariance

The geographical separation of a population, leading to speciation.

pellicle

interlocking protein strips

Who were important naturalists who helped develop the theory of evolution by natural selection?

Charles Darwin and Alfred Russell Wallace

Were there any other naturalists proposing less accepted theories around this time, as well?

yes, Jean-Baptiste Lamarck theory was inheritance of acquired characteristics( if you got really strong, your offspring would be strong too)

What are the three principles of nature that Darwin proposed would inevitably lead to natural selection?

1. Characteristics of organisms are inherited, or passed from parent to off spring.
2. More offspring are produced than are able to survive.
3. Offspring vary among each other in regard to their characteristics and those variations are inherited

Who were Peter and Rosemary Grant and what did their research show?

studied Galápagos finch populations every year since1976; found strong evidence of natural selection(difference in shape of birds peaks)

What is divergent evolution?

when two species evolve in different directions from a common point

What is convergent evolution?

similarity that arises through evolution independently in different species(animals in the tundra have evolved to have white fur bc of their environment)

What is a homologous structure?

share similarities due to inheritance from a common ancestor

What is the Modern Synthesis?

the coherent understanding of the relationship between natural selection and population genetics

What is the difference between microevolution and macroevolution?

microevolution = change of a population over time(small change, adaption)

macroevolution = evolution of new species (large change, speciation)

What is population genetics?

The study of allele frequencies in a population. (what happens to all the alleles (gene variant) in a population)

What is the Hardy-Weinberg Equilibrium?

the amount of genetic variation in a population will remain constant from one generation to the next in the absence of disturbing factors.

What are the forces that break Hardy-Weinberg Equilibrium?

-natural selection
-mutation
- genetic drift
-migration into or out of a population

What are the two types of sexual selection?

intrasexual selection =Competition between members of the same sex for access to mates

intersexual selection = When one sex chooses which members of the opposite sex to mate with (peacock showing off feathers)

What are the mechanisms of evolution?

mutation, migration, genetic drift, natural selection

What are the primary lines of evidence for evolution?

Molecular Biology, Biogeography, Anatomy and Embryology, and Fossil record, convergent

What are the two modes of speciation?

Allopatric speciation ("other homelands") = speciation due to a geographic separation of populations from a parent species

Sympatric speciation ("same homeland") = speciation occurring within a parent species while remaining in one location

What is binomial nomenclature?

system of naming species in which each species is given a two-part name (Genus species)

What are the rules of binomial nomenclature?

The Genus name is written first and has a capitalized first letter. The Species name is written second and is not capitalized. specific epithet =a particular species. (italics and latin)

What is the difference between homologous and analogous structures?

homologous structures = similar structures inherited from a common ancestor

analogous structure =characteristic that is similar occurs by adaptive convergence(convergent evolution)

What are the three domains of life?

Bacteria, Archaea, Eukarya

Which domains comprise the prokaryotes?

Bacteria and Archaea

What was the atmosphere of early Earth like?

atmosphere was anoxic (no oxygen) only those organisms that can grow without oxygen(anaerobic organisms) were able to live

What helped change Earth's early atmosphere?

Evolution of cyanobacteria allowed for oxygenation of atmosphere

What are the three shapes of prokaryotes?

cocci (spherical), bacilli (rod-shaped), and spirilla (spiral-shaped,cork screw)

What is the cell wall of bacteria like?

Bacterial cell walls contain peptidoglycan(polymer of sugars and amino acids)

What are the differences between gram-positive and gram-negative bacteria?

Gram-Positive: thick layer of peptidoglycan(plasma membrane)

Gram-Negative: thin peptidoglycan layer and is surrounded by an additional outer membrane(2 plasma membranes)

What are the primary modes of reproduction in bacteria and how do they differ?

binary fission, budding= asexual
conjugation= where one bacterium transfers a piece of DNA to another through a connecting tube

transformation= the process where a bacterial cell takes up free DNA from its environment and incorporates it into its own genome

transduction= dna comes in through virus and injects itself

How did organelles of eukaryotes evolve and what is the process called?

endosymbiotic theory = eukaryotes are a product of one prokaryotic cell living within another and evolving together over time

What are the ancestors of the mitochondria and chloroplasts?

Mitochondria= evolved from aerobic bacteria
Chloroplast= evolved from photosynthetic prokaryote

Which groups of organisms from this chapter are unicellular?

bacteria, archaea, fungi(yeast), protists(sometimes), some green algae, and viruses, Phylum Chytridiomycota

Which are multicellular organisms?

plants and animals and fungi, protist

Which protist groups are most closely related to animals?

choanoflagellates

What traits are shared among the protists?

• Few shared traits
• Almost all are aquatic & mobile

Why do protists share so few traits?

the term "protist" is essentially a catch-all category for eukaryotic organisms that aren't classified as plants, animals, or fungi

Do the cell walls of fungi share a similar structure to other cell walls discussed in thischapter?

No, fungal cell walls are not structurally similar to other cell walls.
• fungal cells are surrounded by a thick cell wall
• contains chitin and glucan

What are the major parts of the fungal body?

• Thallus = vegetative body offungus
• Hyphae = slender, thread-like extensions of fungal body
• Mycelium = mass of hyphae

How do fungi get their nutrition?

• Heterotrophs; decomposers
• Digestion occurs outside of body,then nutrition is absorbed

What are some important symbiotic relationships that fungi form?

Mycorrhiza = the association between vascular plant roots and their symbiotic fungi

Lichens = a fungus living in close contact with a photosynthetic organism

What is the cell wall of plants made of?

cellulose

What protist group is most closely related to land plants?

green algee

What are some important adaptation to life on land shared among the land plants?

• Cuticle = waxy layer covering aerial portions of plants prevent water loss
• Stomata = pores on the surface of leaves that function in gas exchange
• Gametangia = sex organ of plants, gametes
• Embryo = young plant

The evolution of what cells/tissues allowed for plants to grow taller and away from constant water sources?

vascular tissue

Which groups of plants are gametophyte dominant, which are sporophyte dominant?

gametophyte dominant= phylum ant., phylum hepta., phylum bryo.
sporophyte dominant= phylum lyco., phylum pter.

What are the major groups of nonvascular seedless plants?

Phylum Hepatophyta(liverworts), Phylum Anthocerophyta(hornworts), and Phylum Bryophyta(mosses), collectively called bryophytes; they lack vascular tissue

What characteristics do bryophytes share?

shared traits
• Lack xylem and phloem
• Lack true leaves and roots

-lack vascular tissue

Where do characteristics of bryophytes differ?

-Phylum Hepatophyta have hairlike rhizoids.

-Phylum Bryophyta have No true roots and hair-like rhizoids, may have primitive water

-Phylum Anthocerophyta has spores

What cells/tissues do the vascular plants have that non-vascular lack?

Xylem = tissue that move water and minerals
Phloem = tissue that moves sugars

What are the major groups of vascular seedless plants?

Phylum Lycopodiophyta (club mosses) and Phylum Pteridophyta (ferns, horsetails)

What are the characteristics of vascular seedless plants?

true roots, stems, and leaves

What are the major groups of seed plants?

angiosperms-enclosed in fruit and gymnosperms-naked seeds

What are their characteristics of seed plants?

Gymnosperms
• "Gymno" = naked, "sperm" =seed
• Unprotected seeds
Angiosperms
• Flowering plants

What are the parts of a flower?

Calyx(sepals), Corolla(Petals), Androecium (stamen), and Gynoecium (carpels)

What is a fruit?

fertilized and ripened ovary