Unit 9: Inheritance

Question 1

Complete Dominance

Answer 1

One trait fully overpowers another

Question 2

Incomplete Dominance

Answer 2

Incomplete dominance is a form of inheritance in which a gene or trait has two different alleles that are partially expressed in a heterozygous condition, producing an intermediate phenotype that is different from either parent but contains features of both

Question 3

Codominance

Answer 3

a form of inheritance wherein the alleles of a gene pair in a heterozygote are fully expressed. As a result, the phenotype of the offspring is a combination of the phenotype of the parents. Thus, the trait is neither dominant nor recessive

Question 4

Sex-linked traits

Answer 4

Sex-linked traits are characteristics that are determined by genes located on the sex chromosomes. If a gene is found only on the X chromosome and not the Y chromosome, it is said to be a sex-linked trait

Question 5

Polygenic Inheritance

Answer 5

a non-Mendelian pattern of inheritance in which a particular trait is produced by the interaction of genes

Question 6

Pleiotropy

Answer 6

a single gene influencing two or more distinct phenotypic traits : the quality or state of being pleiotropic

Question 7

Genotype

Answer 7

The combination of alleles

Question 8

Phenotype

Answer 8

The expression of the genotype as an observable trait (physical appearance)

Question 9

Homozygous

Answer 9

Two identical alleles

Question 10

Heterozygous

Answer 10

Two different alleles

Question 11

Dominant Allele

Answer 11

Produces a dominant phenotype even in the presence of a recessive allele (dominant phenotype observed in homozygous and heterozygous organisms)
Represented with capitalized first letter of the trait

Question 12

Recessive Allele

Answer 12

Only produces a recessive phenotype in the absence of a dominant allele (recessive phenotype only observed in homozygous recessive organisms)
Represented with the lowercase first letter of the dominant version of the trait

Question 13

Heterozygote

Answer 13

A heterozygote is an individual that has 2 different alleles for the gene being investigated. (Example: genotype Bb)

Question 14

True Breeding

Answer 14

homozygous for all characteristics being tested

Question 15

Monohybrid Cross

Answer 15

one parent is homozygous dominant and the other is homozygous recessive for the 1 characteristic tested

Question 16

Law of Segregation

Answer 16

each gamete randomly receives only one copy of each gene. (this is because the homologous chromosomes separate during meiosis)