Study Guide For Exam Two Bio

Front 1

pattern of inheritance
Dominance

Back 1

conditions that manifest in heterozygotes (individuals with just one copy of the mutant allele)

Front 2

recessive

Back 2

conditions are only manifest in individuals who have two copies of the mutant allele (are homozygous)

Front 3

x-linked

Back 3

the gene that encodes for the trait is located on the x chromosome

Front 4

codominant

Back 4

genetics of or relating to two alleles of a gene pair in a heterozygote that are both fully expressed

Front 5

mendel’s laws relating to patterns of genetics/inheritance

Back 5

1. Segregation: In diploid organisms, chromosome pairs (and their alleles) are separated into individual gametes (eggs or sperm) to transmit genetic information to offspring.


2. Dominance: A dominant allele completely masks the effects of a recessive allele. A dominant allele produces the same phenotype in heterozygotes and in homozygotes.

3. Independent assortment: Alleles on different chromosomes are distributed randomly to individual gametes.

Front 6

evidence for the theory of evolution

Back 6

fossil record, comparative anatomy, biogeography, comparative embryology, comparative molecular biology

Front 7

artificial selection

Back 7

the process by which humans breed other animals and plants for particular traits.

Front 8

natural selection

Back 8

is the gradual process by which biological traits become either more or less common in a population as a function of the effect of inherited traits on the differential reproductive success of organisms interacting with their environment. It is a key mechanism of evolution.

Front 9

survival of fittest

Back 9

a way of describing the mechanism of natural selection.

Front 10

types of extinctions

Back 10

Coextinction, Mass Extinction,

Front 11

Hardy Weinberg assumptions

Back 11

1. Mating is random
2. No mutations are arising
3. No gene flow
4. No natural selection
5. Population size is infinitely large

Front 12

Founder effect

Back 12

is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population.

Front 13

Bottleneck effect

Back 13

occur when a population’s size is reduced for at least one generation

Front 14

pre- and postzygotic barriers

Back 14

prezygotic barriors:prevent mating or fertilization between different species
postzygotic barriers:reproductive barrier that operates should interspecies mating occur and form hybrid zygotes

Front 15

allopatric speciation

Back 15

or geographic speciation is speciation that occurs when biological populations of the same species become vicariant — isolated from each other to an extent that prevents or interferes with genetic interchange.

Front 16

parapatric speciation

Back 16

is the relationship between organisms whose ranges do not significantly overlap but are immediately adjacent to each other; they only occur together in a narrow contact zone.

Front 17

sympatric speciation

Back 17

is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region.