Genetics

Question 1

Basic unit of inheritance

Answer 1

Gene

Question 2

The physical location of a gene on a chromosome

Answer 2

Locus

Question 3

Alternative forms of a gene on a chromosome

Answer 3

Allele

Question 4

Genetic constitution of an individual

Answer 4

Genotype

Question 5

Observed expression of a gene (physical manifestations)

Answer 5

Phenotype

Genotype plays a role (environment and other genes also play a role)

Question 6

Identical alleles at a single locus

Answer 6

Homozygous

Question 7

Different alleles at a single locus

Answer 7

Heterozygous

Question 8

Condition seen in both the homozygous and the heterozygous; only one copy of the mutant allele is necessary for phenotypic expression

Answer 8

Dominant

Question 9

A condition seen only in the homozygote; requires two copies of the mutant allele for phenotypic expression

Answer 9

Recessive

Question 10

Dominant and recessive refer to ___________ expression

Answer 10

Phenotypic

Not expression of the gene itself

Question 11

Nonsex chromosome

Humans have 22

Answer 11

Autosome

Question 12

X or Y chromosome

Answer 12

Sex chromosome

Question 13

Two copies of each chromosome

Answer 13

Diploid

Question 14

One copy of each chromosome

Answer 14

Haploid

Question 15

All cells in the body EXCEPT gamete

Always diploid

Answer 15

Somatic cells

Question 16

Sperm/egg cells

Always haploid

Answer 16

Gametes

Question 17

Produced by the effect of a single gene, usually transmitted in simple patterns as autosomal dominant, autosomal recessive, or X-linked

Answer 17

Single gene disorders

AKA mendelian disorders or monogenic disorders

Question 18

Deviation from the normal chromosome number or structure

Answer 18

Chromosome abnormalities

Question 19

Combined effects of multiple genetic and non-genetic influences

Answer 19

Multifactorial traits

Question 20

Incidence of genetic disease by age 25

Answer 20

79/1000

8%

Question 21

A disease or condition that is present at birth.

Can be hereditary or acquired

Answer 21

Congenital

Question 22

What is responsible for about 50% of spontaneous abortions?

Answer 22

Chromosomal abnormalities

Question 23

__% of the population will suffer from a disorder with a genetic component during their lifetime.

Answer 23

60

Question 24

How many mutant alleles are needed for an autosomal dominant disease to be expressed?

Answer 24

Only one

Question 25

Autosomal dominant diseases often involve..

Answer 25

Non-catalytic proteins

Question 26

Autosomal dominant diseases

Answer 26

Familial hypercholesterolemia Huntington disease Myotonic dystrophy Neurofibromatosis type 1 Osteogenesis imperfecta Marfan syndrome

Question 27

Probability that offspring of a couple will have the genetic disease

Answer 27

Recurrence risk Each reproductive event is statistically independent of all previous events

Question 28

In autosomal dominant, what is the upper case? Lower case? Which is the mutant allele?

Answer 28

Dominant allele Recessive allele The dominant allele is the mutant allele