Evolution

Question 1

Lamarckian Evoluation

Answer 1

• new organs or changes in existing ones arose b/c of the needs of the organism
• amount of change was thought to be based on the disuse of the organ

Question 2

Darwin’s Theory of Natural Selection

Answer 2

-pressure in the environment select for the organism most fit to survive and reproduce

Question 3

Overpopulation

Answer 3

more offspring are produced than can survive

Question 4

Variations

Answer 4

offspring naturally show differences in their characteristics compared to those of their parents

Question 5

Competition

Answer 5

the developing population must compete for the necessities of life

Question 6

Natural Selection

Answer 6

species have variations that give them advantage over other members of the species

Question 7

Inheritance of the Variations

Answer 7

individuals that strive to adulthood reproduce and transmit favorable genes to offspring (genes will dominate gene pool)

Question 8

Evolution of New Species

Answer 8

accumulation of favorable changes eventually results in such significant changes in the gene pool that we can say new species has evolved

Question 9

Speciation

Answer 9

the evoluation of new species, which are groups of individuals that can interbreed freely with each other, but not with members of other species

Question 10

demes

Answer 10

local populations formed within a species. if demes, become isolated, speciation may occur

Question 11

phylogeny

Answer 11

a branching tree on which the common ancestor is found at the trunk and the modern species are found at the tips of the branches

Question 12

convergent evolution

Answer 12

groups among the branches often develop similar traits

Question 13

Parallel Evoluation

Answer 13

similar to convergent evolution but occurs when a more recent ancestor can be identified

Question 14

Divergent Evolution

Answer 14

occurs when species with a shared ancestor develop differing traits due to dissimilarities between their environments

Question 15

Adaptive Radiation

Answer 15

the emergence of a number of lineages from a single ancestral species

Question 16

Population

Answer 16

includes all members of a particular species inhabiting a given location

Question 17

Gene Pool

Answer 17

the sum total of all the alleles for any given trait in the population

Question 18

Gene Frequency

Answer 18

the decimal fraction representing the presence of an allele for all members of a population that have the particular gene

Question 19

The Hardy-Weinberg Principle

Answer 19

• evolution can be viewed as a result of changing gene frequencies within a population
• when gene frequencies of a population are not changing, the gene pool is stable and the population is not evolving.
• only true in an IDEAL population: the pop is very large, no mutations affect the gene pool, mating between individuals in the population is random, there is no net migration of individuals into or out of the population, the genes in the population are equally successful @ reproducing

Question 20

Microevolution

Answer 20

• real populations have unstable gene pool and migrating populations
• agents of microevolution: natural selection, mutation, assortive mating, genetic drift, and gene flow

Question 21

Natural Selection

Answer 21

genotypes with favorable variations are selected through natural selection

Question 22

Mutation

Answer 22

gene mutations change allele frequencies in a population, shifting gene equilibria by introducing additional alleles

Question 23

Assortive Mating

Answer 23

mates are chosen according to criteria such as phenotype and proximity, the relative genotype ratios will be affected and will depart from the predictions of the Hardy-Weinberg equilibrium

Question 24

Genetic Drift

Answer 24

refers to changes in the composition of the gene pool due to chance (also called founder effect)

Question 25

Gene Flow

Answer 25

migration of individuals between populations will result in a loss or gain of genes

Question 26

Fossil Record

Answer 26

direct evidence of evolutionary change

Question 27

Types of Fossils

Answer 27

can be found in rock, tar pits, ice, and amber

Question 28

Petrification

Answer 28

the process by which minerals replace the cells of an organism

Question 29

Imprints

Answer 29

impressions left by an organism

Question 30

Molds

Answer 30

form hollow spaces in rocks as the organisms within decay

Question 31

Casts

Answer 31

formed by the minerals deposited in molds

Question 32

Homologous Structures

Answer 32

have the same anatomical features and evolutionary origins. Although anatomical features may be similar, their functions may not be

Question 33

Analogous Structures

Answer 33

have similar functions but may have different evolutionary origins and entirely different patters of development

Question 34

Comparative Embryology

Answer 34

stages of development of the embryo resemble the stages in an organism's evolutionary history

Question 35

Comparative Biochemistry (Physiology)

Answer 35

most organisms demonstrate the same needs and metabolic processes

Question 36

Vestigial Structures

Answer 36

have no known current function but apparently had some ancestral function

Question 37

Geographic Barriers

Answer 37

species multiplication is generally accompanied by migration to lessen intraspecific competition

Question 38

The Heterotroph Hypothesis

Answer 38

first forms of life lacked the ability to synthesize their own nutrients. these organisms depended upon outside sources for food

Question 39

Evidence of Organic Synthesis

Answer 39

Stanley L. Miller stet out to demonstrate that the application of UV radiation, heat, or a combination of these to a mixture of methane, hydrogen, ammonia, and water would result in the formation of complex organic compounds

Question 40

Formation of Primitive Cells

Answer 40

coacertive droplets (a duster of colloidal molecules surrounded by a shell of water) may have formed the first primitive cells