Genetics and Populations - Inheritance: Key Terms

Question 1

Allele

Answer 1

One of a number of alternative forms of a gene

Question 2

Allele frequency

Answer 2

The number of times an allele occurs within a gene pool

Question 3

Autosomal linkage

Answer 3

When two or more genes are carried on the same autosome so are inherited together

Question 4

Chi squared test

Answer 4

A statistical test to test if a set of data is associated with a certain variable or a factor by testing the difference between observed values and expected values

Question 5

Codominant

Answer 5

When one allele is not recessive to the other, so the heterozygote has an intermediate phenotype

Question 6

Dihybrid

Answer 6

The inheritance of two different characteristics controlled by two separate genes, which are inherited independently from one another

Question 7

Diploid

Answer 7

Cells that contain two sets of chromosomes in the nucleus

Question 8

Dominant

Answer 8

The allele expressed even when present with the recessive allele of the same gene

Question 9

Epistasis

Answer 9

When the allele of one gene affects or masks the expression of another in the phenotype

Question 10

Gene

Answer 10

A sequence of DNA on a chromosome that codes for one protein

Question 11

Gene pool

Answer 11

The total number of alleles in a particular population at a specific time

Question 12

Genotype

Answer 12

The alleles possessed by an individual

Question 13

Hardy-Weinburg Principle

Answer 13

A principle that provides a mathematical equation that can be used to calculate the frequencies of the alleles of a gene in a population

Question 14

Heterozygous

Answer 14

The condition in which the alleles of a gene at the same locus are different

Question 15

Homozygous

Answer 15

The condition in which the alleles of a gene are the same

Question 16

Locus

Answer 16

The fixed position of a gene on a chromosome

Question 17

Monohybrid

Answer 17

The inheritance of a single gene

Question 18

Multiple alleles

Answer 18

Where there are more than two alleles , of which only two can be present at the loci of an individual’s homologous chromosomes

Question 19

Phenotype

Answer 19

The characteristics of an organism resulting from its genotype and the effects of its environment

Question 20

Phenotypic ratio

Answer 20

The relative number of offspring manifesting a particular trait or combination of traits

Question 21

Recessive

Answer 21

The allele expressed only in the presence of another identical allele

Question 22

Sex-linkage

Answer 22

Genes carried on the X or Y chromosomes