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57 Cards in this Set

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Bottleneck Effect
Genetic drift resulting from a drastic reduction in population size
~Northern Elephant Seal
~hunted down to 20 then bred and now many with one allele
Phylum Chordata
bilateral symmetry, 3 body layers, coelom
DEUTEROSTOME
post anal tail, dorsal hollow nerve cord
ex: Tunicate (larval has chordate features, adult for rudimentary)
Lancelets (adult retains tunicate features
Macroevolution
The main events in the evolutionary history of life on earth
Protostome
MOLLUSCS, ANNELIDS, ARTHROPODS
~mouth develops first
Sympatric Speciation
The formation of a new species as a result of a genetic change that produces a reproductive barrier betwee the changed population (mutants) and the parent population

SAME FATHER LAND
Deuterostome
ECHINODERMS AND CHORDATES
Anus forms first
Evolution
~genetic change in a population or species over generations
~all the changes that transform life on earth
~the heritable changes that have produced earth's diversity of organisms.
Class Osteichthyes
(Bony Fishes)
~lateral line system
~swim bladder-control where float
~ex: ray-finned or lobe-finned fishes
Phylum Echinoderm
~radial as adults, bilateral as larva
3 body layers
DEUTEROSTOMES
coelom
ex: sea star, urchin, cucumber
Allele
An alternative form of a gene
Class Agnatha
~no hinged jaw
~ex: lamprey
Gene Pool
All the genes in a population at one time
Class Chondrichthyes
(Cartilagenous fishes)
~flexible skeleton of cartlige
~special sensory organs
-electrosensor
- lateral line system (detects vibrations)
ex: sharks, rays, skates
Polyploid
More than two sets of chromosomes
Class _____________
(Amphibians)
double life
first water, then both
ex: frogs, toads, salamanders
Taxonomy
The branch of biology concerned with identifying, naming, and classifying species
Class ________
(Birds)
flight, feathers, hollow bones
~endothermic: internal temp metabollically regulated
Class _______________
(Mammals)
hair, mammary glands (milk)
parental care
Monotremes: young hatched from eggs ~ platypus
Marsupials: "pouched-mammals"
Eutherians:"placental mammals"
Class __________
(Reptiles)
eggs have shell & amniotic sac
~keratin, scales: waterproof
~ectothermic: regulate heat by environment
ex: snakes, lizards, dinos
Allopatric Speciation
The formation of a new species as a result of an ancestral population's becoming isolated by a geographical barrier

DIFFERENT FATHER LAND
Natural Selection
~Differential success in reproduction by different phenotypes resulting from interactions with the environment.
~Evolution occurs when natural selection produces change in the relative frequencies of alleles in a population's gene pool
Phylum Arthropoda
bilateral symmetry, 3 body layers, coelom
protostome
jointed appendages, exoskeleton
head, thorax, abdomen
ex: Insects (cricket) Millipedes, Crustaceans (barnacles, crabs), Arachrids (Spiders)
Hominids
BIPEDIALISM
further brain development

Astralopithecus--Homo Habilis--Homo Erectus--Homo Sapiens

Biogeography
The geographical distribution of species
Homology (Homologous traits)
~Structures that are similar in different species based on common ancestor
Artificial Selection
Selective breeding of domesticated plants and animals to promote the occurence of desirable traits in offspring
Genetic Drift
A change in the gene pool of a population due to CHANCE
Anthropoids
Monkeys
~forelimbs & hindlimbs same length

Apes
~no tails, longer forelimbs
ex: orangutans, gorillas, chimps
Prosimians
tree dwelling
smaller brains
ex: lemurs and tarsiers
Genotype
The genetic makeup of an organism
Phylum Cnidaria
Radial symmetry
2 body layers
ex: Hydras, jellyfish, anenomes, corals
Phylum Nematoda
bilateral symmetry
3 body layers
pseudocoelom...mouth and anus
ex: roundworms
Phylogenetic Tree
A branching diagram that offers a hypothesis about evolutionary relationships among organisms
Phylum Porifera
asymmetrical
0 embryonic tissue layers
no body cavity
sponges
Gene Flow
a gain or loss of alleles from a population by the movement of individuals or gametes into or out of the population
5 lines of evidence supporting the theory of evolution
1) fossil record
2) biogeography
3) comparitive anatomy - homologous structures
4) Embryology
5) Molecular Biology
Coelom
A body cavity completely lined with mesoderm
Mutation
rare, random change in DNA
~ultimate source of variability
Convergent Evolution
~Adaptive change resulting in nonhomologous (analogous) similarities among organisms.
~Species from different evolutionary lineages come to resemble each other (evolve analogous structures) as a result of living in very similar environments
Population
A group interacting individuals belonging to one species and living in the same geographic area
Zygote
The fertilized egg, which is diploid, that results from the union of a sperm cell nucleus with an egg cell nucleus
Microevolution
~A change in relative frequencies of alleles in a population over time~
~A change in a population's gene pool over a succession of generations
~Evolutionary changes in species over relatively brief periods of geological time
Phylum Platyhelminthes
bilateral symmetry
3 tissue layers
ex: fluke in lab, tapeworms
What two things need to happen for speciation to occur?
1)reproductive barriers
2) accumulation of differences
Blastula
An embryonic stage that marks the end of cleavage during animal development
~A hollow ball of cells in many species
Polymorphisms
~The existence of different forms
~May pertain to a population where two or more morphs are present in readily noticeable frequencies
Example??
Phylum Annelida
bilateral symmetry, 3 body layers, coelom
protostome
segmentation
ex: earth worm
Hardy-Weinberg Equilibrium
The principle that the shuffling of genes that occurs during sexual reproduction, by itself, cannot change the overall genetic make up of a population... ~5 conditions:
1)large population 2) isolated population
3) no mutations 4) random mating
5) no natural selection
Phylum Mollusca
bilateral symmetry, 3 body layers, coelom
protostome
ex: bi-valves (clams) gastropods (snails) cephalopods (octopus)
mantle - forms shell
radula - scraping organ
Stabilizing Selection
Natural selection that favors intermediate variants acting AGAINST EXTREME phenotypes
Mesoderm
tissue filled region
Gastrula
Embryonic stage resulting from gastrulation (adds more cells to the embryo and sorts them into distinct cell layers)
~Most have 3 layers...ectoderm, endoderm, mesoderm
Phenotype
The expressed traits of an organism
Directional Selection
Natural selection that acts AGAINST the relatively RARE individuals at one end of a phenotypic range
Ectoderm
body covering
Endoderm
digestive tract
Diversifying Selection
Natural selection that FAVORS EXTREME over intermediate phenotypes