Mendelian Genetics Chap. #8

Question 0

What is a Genotype?

Answer 0

A two-letter set that represents the alleles an organism possesses for a certain trait.

Question 1

What is an Allele

Answer 1

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

Question 2

What is a phenotype.

Answer 2

The observable expression of an organisms genes.

Question 3

What is a homozygous genotype?

Answer 3

A genotype in which both alleles are identical.

Question 4

What is True breeding?

Answer 4

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

Question 5

What is a Heterozygous genotype?

Answer 5

A genotype with two different alleles.

Question 6

What is a recessive allele?

Answer 6

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

Question 7

What is a dominant allele?

Answer 7

In allele that will determine the phenotype just one is present in the genotype.

Question 8

What is a pedigree?

Answer 8

A diagram that follows a particular phenotype through several generations.

Question 9

What are Autosomes?

Answer 9

Chromosomes that do not determine the sex of an individual.

Question 10

What is a Genetic disease carrier?

Answer 10

A person who is heterozygous in a recessive genetic disorder.

Question 11

Sex chromosomes

Answer 11

Chromosomes that determine the sex of an individual.

Question 12

What it Autosomal inheritance?

Answer 12

Inheritance of a genetic trait not on a sex chromosome.

Question 13

What is sex linked inheritance?

Answer 13

Inheritance of a genetic trait located in the sex chromosomes.

Question 14

What is a mutation?

Answer 14

A radical chemical change in one or more alleles.

Question 15

What is change in chromosome structure?

Answer 15

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

Question 16

What is change chromosome number?

Answer 16

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 17

What are the four principles of genetics?

Answer 17

1. The traits of an organism are determined by its genes.
2. Each organism has two alleles that make up the genotype for given traits.
3. In sexual reproduction, each parent contributes only one of its alleles to its offspring.
4. In each genotype, there is a dominant allele. If it exists in an organism, the trait determined by that dominant factor will be expressed.

Question 18

What is a monohybrid cross?

Answer 18

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

Question 19

What is a dihybrid cross?

Answer 19

A cross between two individuals, concentrating on to definable traits.

Question 20

What is an antigen?

Answer 20

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

Question 21

What is incomplete dominance?

Answer 21

When the alleles of a certain trait share dominance.

Question 22

What is polygenetic inheritance?

Answer 22

The outcome of the interaction of several genes that determine one trait.

Question 23

What is Epistasis?

Answer 23

The situation in which one set of alleles affects how another set of alleles is expressed.

Question 24

What is pleiotropy?

Answer 24

When a single gene can affect multiple observable traits (multiple phenotypes).