Genetics Evolution Mechanics

Question 1

What is evolution?

Answer 1

The change in genetic composition over time.

Question 2

What is evolutionary theory?

Answer 2

The physical genetic changes and how they occur; the past shows the mechanisms of evolutionary change.

Question 3

What are the 3 main ideas of evolution?

Answer 3

1. Species change over time.
2. Descent with modification (speciation or divergence genetics).
3. Natural Selection (Survival and reproduction of individuals based on variation in individual traits).

Question 4

What are phenotypes?

Answer 4

The physical expression of an organism’s genes (eye structure).

Question 5

What is a character?

Answer 5

A specific feature of a phenotype (eye color).

Question 6

What is a trait?

Answer 6

A specific form of a character (brown eyes).

Question 7

What is a heritable trait?

Answer 7

A trait that is at least partially determined by genes (that which can be passed from generation to generation).

Question 8

What is a genotype?

Answer 8

The genetic makeup of a gene (Protein sequencing).

Question 9

What is an allele?

Answer 9

A specific version of a gene (like Mac vs. PC).

Question 10

What is a locus?

Answer 10

A specific point on a chromosome where an allele exists.

Question 11

What is the gene pool?

Answer 11

All of the alleles and loci that make up the variation within a population.

Question 12

What is a population?

Answer 12

A group of individuals that interbreed within a geographical location.

Question 13

What is a mutation?

Answer 13

A change in the nucleotide sequence of an organism’s DNA.

Question 14

What is allele frequency?

Answer 14

How often an allele is seen in a population.

Question 15

What is genotypic frequency?

Answer 15

The proportion of genotypes seen in a population.

Question 16

What is artificial selection?

Answer 16

Human selection based on phenotypes.

Question 17

What is adaptation?

Answer 17

A favored trait evolved through natural selection.

Question 18

What is positive selection?

Answer 18

When a beneficial change is selected favorably.

Question 19

What is purifying selection?

Answer 19

When a deleterious change is selected against.

Question 20

What is gene flow?

Answer 20

A change in the allele frequency of a population.

Question 21

What is genetic drift?

Answer 21

A random change in the allele frequency from generation to generation.

Question 22

What is a population bottleneck?

Answer 22

A mass death event that causes genetic diversity to plummet.

Question 23

What is the founder effect?

Answer 23

Where a new population colonizes an area. Lower genetic diversity results.

Question 24

What is sexual selection?

Answer 24

When one sex non-randomly chooses a mate of the opposite sex.

Question 25

What is a fixed allele frequency?

Answer 25

When a gene becomes monomorphic and has only one type of allele (frequency = 1).

Question 26

What is genetic structure?

Answer 26

The frequency of alleles plus the frequency of genotypes.

Question 27

What are the conditions of Hardy-Weinberg Equilibrium?

Answer 27

1. No genotypic selection.
2. No gene flow.
3. Unlimited population size.
4. Random mating.
5. No mutations occur.

Question 28

What is fitness?

Answer 28

How much a phenotype contributes to the next generation compared to other phenotypes of the same trait.

Question 29

What is stabilizing selection?

Answer 29

Favoring the average characteristic of a population.

Question 30

What is directional selection?

Answer 30

Favoring one direction from the mean, moving the mean left or right (extremes).

Question 31

What is disruptive selection?

Answer 31

Favoring extremes in a population, but not the average expression.