Exam 1

Question 1

Mutations in ______ cells are more important

Answer 1

sex

they are passed on to next generations.

Question 2

Point mutation-

Answer 2

change in one nucleotide

Question 3

Substitution point mutations can be ________ (silent) or ________ (meaningful)

Answer 3

synonymous

non-synonymous

Question 4

Silent mutation-

Answer 4

codon from this mutation specifies the same amino acid as the non-mutated codon. No protein change.

Question 5

Codon-

Answer 5

triplet sequence of nucleotides that specifies a particular amino acid

Question 6

Non-synonymous (meaningful) point mutation-

Answer 6

missense, different amino acid, different protein.

Question 7

Large sections of chromosomal mutations-

Answer 7

deletion, duplication, inversion, insertion, translocation.

Question 8

Gene position may or may not be important in its __________

Answer 8

expression

Question 9

Trisomy 21 is due to _________. Leads to ___________

Answer 9

• nondisjunction, extra T21 chromosome

- Down Syndrome

Question 10

Fusion of a chromosome might be a significant effect in __________

Answer 10

speciation

Question 11

Estimated number of protein coding genes in humans

Answer 11

25,000

Question 12

Gross generalization: mutation rate per generation is:

Answer 12

10^-5 or 10^-6

Question 13

mutation rate (_______) is too low to be main force in evolution. Between _____% of us carry a genetic mutation compared to our parents. Although mutation is too low to be main force of evolution, it is the only source of ___________

Answer 13

• .025 to .25
• 5-44%
• new genes in a species.

Question 14

Mutations increase genetic variability in a _________ and between __________

Answer 14

• population

- populations

Question 15

Gene flow-

Answer 15

movement of alleles from one population to another due to mating between populations.

Question 16

Gene flow inhibits speciation because ____________________

Answer 16

two populations blend their traits and they are now more similar and less likely to genetically diverge from each other.

Question 17

Genetic drift-

Answer 17

random change in allele frequencies

Question 18

The smaller the population, the more chance of significant ________

Answer 18

mutations

Question 19

Two inferences we can make about genetic drift:

Answer 19

1. All populations evolve every generation by genetic drift

2. magnitude of evolution by genetic drift is greater in a smaller population than a larger population

Question 20

The ultimate result of genetic drift is ___________, and all other alleles of the gene have been _______________

Answer 20

• fixation of an allele

- eliminated from the population

Question 21

Bottleneck and Founder effects-

Answer 21

reduction in genetic variability by chance due to reduction in population size (bottleneck) or establishment of a new, founder population.

Question 22

Natural selection-

Answer 22

differences among individuals in reproductive success

Question 23

The unit of natural selection is _________; the unit of evolution is ___________

Answer 23

• the individual organism

- the population (or species)

Question 24

• Adaptation- result of _________

- Individuals are subject to natural selection, whereas populations (or species) _______

Answer 24

• natural selection

- adapt

Question 25

-Adaptation occurs only if differences among individuals in reproductive success have ____________

Answer 25

some inheritable basis.

Question 26

Fundamental Theory of Natural Selection-

Answer 26

opportunity for natural selection is directly related to genetic variability in a population (or species)

Question 27

There must be ____________________ for there to be natural selection.

Answer 27

genetic differences among individuals in a population (or species), and correspondingly phenotypic differences,

Question 28

Natural selection “acts” directly on __________, and indirectly on ____________

Answer 28

• phenotypic variability

- genetic variability

Question 29

Natural selection –

Answer 29

differential reproductive success among individuals in a population (or species).

Question 30

Three “types” of natural selection

Answer 30

stabilizing selection, directional selection, and diversifying selection

Question 31

Stabilizing selection –

-Result is to reduce variability in the _________, but no change in _______

Answer 31

• selection against individuals at both ends of the phenotypic distribution curve.
• distribution curve
• the mean value

Question 32

Directional selection – ____________. Result is a change in the _____________.

Answer 32

• selection for individuals at one end of the phenotypic distribution curve.
• mean value of the distribution

Question 33

Diversifying selection – ____________________. Result is ______________.

Answer 33

• selection against individuals in the intermediate range of the phenotypic distribution curve, and selection for individuals at the ends of the distribution curve
• two modalities in phenotypic distribution

Question 34

Units of natural selection:

Answer 34

• gene
• individual organism
• group (i.e., population)
• species

Question 35

For a “unit” to be subject to natural selection, the trait _____________ and there must be __________.

Answer 35

• must be inheritable

- variance within that unit

Question 36

Units of natural selection

1. Gene-
2. Individual organism-
3. Group (i.e., population)-
4. Species-

Answer 36

• meiotic drive: allele is transmitted to offspring at a rate higher than 50%
• classic Darwinian theory
• individuals in the group sacrifice their reproductive success to ensure group survival
• Species differ among themselves in likelihood of speciation; lineages with high speciation rates persist, whereas those with low speciation rates go extinct

Question 37

Kin selection
1.
2.
also called 3.

Answer 37

1. just more natural selection at level of individual organism
2. Individual may reduce her/his reproductive success by aiding the reproductive success of her/his “kin”
3. altruism

Question 38

Kin selection is simply part of an organism’s ___________ and can be considered to be natural selection among individual organisms.

Answer 38

inclusive fitness

Question 39

Inclusive fitness:

Answer 39

an individual’s genetic contribution to the next generation is based on both one’s own reproduction and by reproduction of one’s relatives.

Question 40

5 concepts of a species:

Answer 40

• Biological species
• Evolutionary species
• Morphological species
• Ecological species
• Recognition species

Question 41

Biological Species:

Answer 41

Group(s) of actually or potentially interbreeding organisms that are reproductively isolated from other such groups.