Module #8 Vocabulary

Question 1

Allele

Answer 1

One of a pair of genes that occupies the same position on homologous chromosomes.

Question 2

Genotype

Answer 2

Two-letter set that represents the alleles an organism possesses for a certain trait

Question 3

Phenotype

Answer 3

The observable expression of an organism’s genes

Question 4

Homogenous Geneotype

Answer 4

A genotype in which both alleles are identical

Question 5

Heterozygous Genotype

Answer 5

A genotype with two different alleles

Question 6

Dominant Allele

Answer 6

An allele that will determine phenotype if just one is present in the genotype

Question 7

Recessive Allele

Answer 7

An allele that will not determine the phenotype unless the genotype is homozygous in that allele

Question 8

Pedigree

Answer 8

A diagram that follows a particular phenotype through several generations

Question 9

Monohybrid Cross

Answer 9

A cross between two individuals, concentrating on only one definable trait

Question 10

Dihybrid Cross

Answer 10

A cross between two individuals, concentrating on two definable traits

Question 11

Autosomes

Answer 11

Chromosomes that do not determine the sex of an individual

Question 12

Sex Chromosomes

Answer 12

Chromosomes that determine the sex of an individual

Question 13

Antigen

Answer 13

A protein that, when introduced in the blood, triggers the production of an antibody

Question 14

Autosomal Inheritance

Answer 14

Inheritance of a genetic trait not on a sex chromosome

Question 15

Genetic Disease Carrier

Answer 15

A person who is heterozygous in a recessive genetic disorder

Question 16

Sex-linked Inheritance

Answer 16

Inheritance of a genetic trait located on the sex chromosomes

Question 17

Mutation

Answer 17

A radical chemical change in one or more alleles

Question 18

Change in chromosome structure

Answer 18

A situation in which a chromosome loses or gains genes during meiosis

Question 19

Change in chromosome number

Answer 19

A situation in which abnormal cellular events in meiosis lead to either none of a particular chromosome in the gamete or more than one chromosome in the gamete

Question 20

True breeding

Answer 20

If an organism has a certain characteristic that is always passed on to its offspring, we say that this organism bred true with respect to that characteristic.

Question 21

Mendel’s principles f genetics 1

Answer 21

(1) the traits of an organism are determined by its genes.

Question 22

Mendel’s principles of genetics - 2

Answer 22

(2) Each organism has two alleles that make up the genotype of a given trait.

Question 23

Mendel’s principles of genetics (3)

Answer 23

(3) in sexual reproduction, each parent contributes ONLY ONE of its alleles to the offspring.

Question 24

Mendel’s principles of genetics (4)

Answer 24

(4) in each genotype, there is a dominant allele. If it exists in an organism, the phenotype is determined by that allele.