Patterns of Inheritance

Question 1

What is polygenic

Answer 1

Trait brought about my multiple genes

Question 2

What is the locus

Answer 2

The location of a gene, or a sequence of genes, on a chromosome.

Question 3

What is epistasis

Answer 3

Epistasis is a genetic phenomenon where one gene masks or modifies the expression of another gene at a different location, altering typical Mendelian inheritance ratios and resulting in different phenotypes

Question 4

What is the ratio of the phenotypes of a dihybrid cross?

Answer 4

9:3:3:1 phenotypic ratio when crossing two individuals heterozygous for two traits

Question 5

Why would a ratio of inheritance be incorrect

Answer 5

Genes are linked
Epistasis
(Crossing over)
(Random fertilization/fusion)

Question 6

Do individuals evolve?

Answer 6

No, populations evolve over generations.

Question 7

What four levels does evolution work at?

Answer 7

Molecular
Cellular
Individual
Population

Question 8

What is gene pool?

Answer 8

Total number of alleles in a population at any one time.

Question 9

What is the modern definition of evolution?

Answer 9

A change in allele frequency from one generation to the next.

Question 10

Evolution stages (simplified).

Answer 10

Change in environment

Natural selection favors certain traits within individuals

Over time the allele frequency of favored traits increases

Population evolves

Question 11

What is microevolution?

Answer 11

Microevolution is the change in allele frequencies (gene variants) within a population over short periods artificial selection, mutation, gene flow, genetic drift.

Question 12

Gene flow?

Answer 12

Movement of alleles from one population to another.

Due to migration, non random mating.

Question 13

Genetic drift?

Answer 13

Random change in allele frequency in a population.

Question 14

What is a bottle neck effect?

Answer 14

Drift caused by an event, which drastically reduces population size. Catastrophe or colonization can cause this.

Question 15

What is macroevolution

Answer 15

Any evolutionary change at or above species level, splitting of species into two or more species/ transformation.

Question 16

What is speciation

Answer 16

Final result of changes in gene pool allele and genotypic frequencies.

Question 17

Factors that produce variation?

Answer 17

Recombination
Segregation
Independent assortment
Mutation

Question 18

Factors that redistribute variation?

Answer 18

Gene flow
Genetic drift
Natural selection.

Question 19

What does a population bottleneck lead too?

Answer 19

Genetic drift, only when an event drastically reduces population size.

An example would be northern elephant seals.

Question 20

What is the founder effect?

Answer 20

A type of genetic drift, allele frequencies are altered by creating a new small population from remnants of a larger population.

Question 21

What are the assumptions of hardy-weinberg?

Answer 21

No selection
No mutation
No migration
Large population
Random mating