Mendelian Genetics Vocab

Question 1

Allele

Answer 1

Alternative versions of a gene that produce distinguishable phenotypic effects

Question 2

Carrier

Answer 2

Heterozygotes that may transmit their recessive disorder allele to their offspring

Question 3

Codominance

Answer 3

Both alleles affect the phenotype in separate distinguishable ways

Question 4

Dominant

Answer 4

An allele that is fully expressed in the phenotype of a heterozygote

Question 5

Epistasis

Answer 5

A gene at one locus alters the phenotypic expression of a gene at a second location

Question 6

F1 generation

Answer 6

The first filial generation of a hybridization

Question 7

F2 generation

Answer 7

The second filial generation of a hybridization

Question 8

Genotype

Answer 8

An organism’s genetic makeup

Question 9

Heterozygous

Answer 9

An organism with two different alleles for a single particular gene

Question 10

Homozygous

Answer 10

An organism having a pair of identical alleles for a characteristic

Question 11

Hybridization

Answer 11

The mating, or crossing, of 2 true-breeding varieties

Question 12

Incomplete Dominance

Answer 12

The phenotypes of heterozygotes is intermediate between the phenotypes of individuals homozygous for either allele

Question 13

Law of Independent Assortment

Answer 13

States each pair of alleles segregates independently of other pairs of alleles during gamete formation

Question 14

Law of Segregation

Answer 14

States that the two alleles for a heritable character during gamete formation end up in different gametes

Question 15

Multifactorial

Answer 15

Many factors, both genetic and environmental, collectively influence phenotype

Question 16

P Generation

Answer 16

The true breeding parents in hybridization (parental generation)

Question 17

Pedigree

Answer 17

A family tree describing the interrelationships of parents and children across the generations

Question 18

Phenotype

Answer 18

An organism’s expressed traits

Question 19

Pleiotropy

Answer 19

Genes that have multiple phenotypic effects

Question 20

Polygenic Inheritance

Answer 20

An additive effect of two or more genes on a single phenotypic character

Question 21

Punnett Square

Answer 21

A diagrammatic device for predicting allele composition of offspring from a cross between known individuals

Question 22

Quantitative Characters

Answer 22

A heritable feature that varies continuously over a range rather than an either-or fashion

Question 23

Recessive

Answer 23

An allele whose phenotypic effect is not observed in a heterozygote

Question 24

Self-Pollinate

Answer 24

The pollination of a flower by pollen of the same flower or from another flower on the same plant

Question 25

Testcross

Answer 25

Breeding an individual with an unknown genotype with an individual with a known genotype in order to observe the results to determine the unknown genotype

Question 26

True-Breeding

Answer 26

Referring to plants that produce offspring of the same variety when they self-pollinate