Unit 9: Population Genetics

Question 1

Acquired inheritance

Answer 1

a theory proposed by Lamarck that an organism will develop a trait by using it; for example, a giraffe’s neck will get longer because of stretching to reach leaves high in a tree

Question 2

Acquired traits

Answer 2

traits an organism develops within its lifetime, such as strong muscles

Question 3

Adaptation

Answer 3

any function, structure, or behavior that allows an organism to be successful in their environment so they survive and reproduce

Question 4

Adaptive radiation

Answer 4

the process by which a single species evolved into many new species to fill available niches

Question 5

Allele frequency

Answer 5

how often an allele occurs in a gene pool relative to the other alleles for that gene

Question 6

Allopactric speciation

Answer 6

new species form when a geographic barrier, such as a canyon or river,
separates a population

Question 7

Analogous structures

Answer 7

structures that are similar in unrelated organisms because the structures perform the same job, but they are not inherited from a common ancestor

Question 8

Artificial selection

Answer 8

breeding done by humans to select certain traits or characteristics in the plant or animal

Question 9

Behavioral isolation

Answer 9

a type of reproductive isolation that prevents organisms from reproducing due to the presence or absence of certain behaviors (such as mating rituals)

Question 10

Biogeography

Answer 10

the study of the distribution of organisms, species, ecosystems, and biomes around the world

Question 11

Bottleneck effect

Answer 11

a type of genetic drift that occurs when a population suddenly gets smaller due to a natural disaster

Question 12

Camouflage

Answer 12

species has an appearance (color, shape, or pattern) that help blend into the background

Question 13

Charles Darwin

Answer 13

an English naturalist who developed the theory of evolution

Question 14

Comparative anatomy (morphology)

Answer 14

the study of the similarities and differences in the structures of
different species

Question 15

Comparative embryology

Answer 15

the study of similarities and differences in the embryos of different species

Question 16

Directional stabilization

Answer 16

selection occurs when one of the two extreme phenotypes is selected, so the majority of the population’s characteristics shift towards that end

Question 17

Disruptive selection

Answer 17

selection that occurs when phenotypes in the middle of the range are selected against, so two different phenotypes develop

Question 18

Evolution

Answer 18

a change in gene frequencies within a population

Question 19

Fitness

Answer 19

an organism’s ability to survive and produce fertile offspring

Question 20

Fossil

Answer 20

the remains, impression, or trace of a living thing of a former geologic age, and can include pieces of bone, impressions pressed into rocks, or insects trapped in tree resin

Question 21

Fossil record

Answer 21

the information about Earth’s history that can be gathered from fossils

Question 22

Founder effect

Answer 22

a type of genetic drift that occurs if a few individuals start (or ‘found’) a new
population (for example move to a new island or new area

Question 23

Gene flow

Answer 23

occurs when individuals move into or out of a population

Question 24

Gene pool

Answer 24

the combination of all of the genes present in a given population

Question 25

Genetic drift

Answer 25

a random change in allele frequencies that occur in small populations

Question 26

Geographic isolation

Answer 26

prevents organisms from reproducing due to being separated by geographic barriers (such as mountains or rivers)

Question 27

Homologous structure

Answer 27

structures that are similar in related organisms because they were inherited from a common ancestor; they may or may not have similar functions, but they have the same basic pattern of bones

Question 28

Inherited traits

Answer 28

features/characteristics that are passed from one generation to the next

Question 29

Invasive species

Answer 29

plants and animals that are brought to a new habitat and 'bully' the native species to the point where many cannot survive

Question 30

Jean Baptiste

Answer 30

French naturalist that proposed the theory of acquired characteristics (an organism will develop a trait by using it; for example, a giraffe's neck will get longer because of stretching to reach leaves high in a tree)

Question 31

Lyell (Charles)

Answer 31

English geologist that published book Principles of Geology that explained geological processes have shaped the Earth's surface, so the Earth must be very old

Question 32

Macroevolution

Answer 32

large scale evolutionary change over geologic time and results from microevolution taking place over many generations

Question 33

Malthus (Thomas)

Answer 33

English economist that argued human populations grow faster than resources so famine and disease break out, which keeps populations in check

Question 34

Microevolution

Answer 34

the study of changes in the gene pool of a species' population over time

Question 35

Mimicry

Answer 35

an adaptation in which a species uses appearances to copy, or mimic, another species (example - a nonpoisonous frog may evolve to look like a poisonous frog)

Question 36

Natural selection

Answer 36

beneficial traits (like camouflage) produce more offspring than others, and results in a population that has more of those traits

Question 37

Naturalist

Answer 37

a person who studies nature, especially a zoologist (studies animals) or botanist (studies plants); similar to an environmental biologist

Question 38

Paleontologist

Answer 38

scientists who study fossils

Question 39

Population genetics

Answer 39

the science that focuses on evolution within populations

Question 40

Postzygotic barrier

Answer 40

a reproductive barrier that reduces the viability (reproductive capacity) of hybrid offspring; a mule is an example - a horse and donkey produce a mule which is not fertile

Question 41

Prezygotic barrier

Answer 41

anything that prevents mating and fertilization; habitat isolation, behavioral isolation, temporal isolation, and mechanical isolation are examples

Question 42

Reproductive barrier

Answer 42

barriers that prevent members of a species from mating and producing offspring; three types (temporal, geographic, and behavioral)

Question 43

Speciation

Answer 43

the process by which a new species evolves

Question 44

Species

Answer 44

a group of organisms that can breed and produce fertile offspring

Question 45

Stabilizing selection

Answer 45

average phenotypes become more common as selection occurs when phenotypes at both extremes are selected against

Question 46

Sympatric speciation

Answer 46

new species form from some type of reproductive barrier (either prezgotic or postzygotic

Question 47

Temporal isolation

Answer 47

prevents organisms from reproducing due to differences in the time of breeding schedules

Question 48

Theory of evolution

Answer 48

the change in a species over time due to natural selection

Question 49

Vestigial structures

Answer 49

structures that no longer serve a purpose in an organism; examples are human appendix, human tailbone, and pelvic bone in whales