Terms Exam 1

Question 1

Inheritance of X trait is dominant in male and recessive in female

Answer 1

Sex-influenced

Question 2

Parents with normal vision produce normal visioned daughters but if the mother is a carrier, then half the sons will be color blind

Answer 2

Recessive sex-linked

Question 3

Homozygosity for overo allele results in all foals suffering from aganglionosis of large intestine and die within a few days after birth

Answer 3

Lethal gene

Question 4

3 consecutive base pairs on mRNA is a codon that specifies an amino acid. There are 64 codons in total and they code for 20 amino acids

Answer 4

Genetic code

Question 5

Interaction between gene alleles resulting in a heterozygote superior to either homozygote for a particular trait

Answer 5

Overdominance

Question 6

Death before puberty for an individual

Answer 6

Semi-lethal

Question 7

The phenotypic effect of genes at one locus is dependent upon what alleles are present at another locus distance from the first locus

Answer 7

Epistasis

Question 8

Expression of trait occurs only in one sex (Ex: milk or egg production)

Answer 8

Sex-limited

Question 9

The existence of more than one grade of a trait

Answer 9

Variable expressivity

Question 10

Having two identical alleles of given gene

Answer 10

Homozygote

Question 11

Allele expressed in phenotype of heterozygote

Answer 11

Dominant

Question 12

Alternative form of a gene

Answer 12

Allele

Question 13

Observable characteristic

Answer 13

Phenotype

Question 14

Cross between individuals both homozygous for two genes

Answer 14

dihybrid cross

Question 15

Alleles of one gene separate into gametes randomly with respect to alleles of other genes

Answer 15

independent assortment

Question 16

Reproductive cells containing one copy of each gene

Answer 16

Gametes

Question 17

Heritable entity that determines characteristics

Answer 17

Gene

Question 18

Separation of two alleles of a gene into different gametes

Answer 18

Segregation

Question 19

Individual with two different alleles for same gene

Answer 19

Heterozygote

Question 20

Offspring of P generation

Answer 20

F1

Question 21

Proportion of individuals carrying particular variant of a gene that also expresses an associated phenotype

Answer 21

Penetrance

Question 22

Cross individual of unknown genotype with homozygous recessive individual

Answer 22

Test cross

Question 23

Doesn’t contribute to heterozygous genotype

Answer 23

Recessive

Question 24

Description of how animal should look/behave

Answer 24

Breed standards

Question 25

Alleles an individual has

Answer 25

Genotype