Chapter 11

Question 0

Each variant for a character

Answer 0

Trait

Question 1

A heritable feature that varies among individuals

Answer 1

Character

Question 2

Organisms that produce offspring of the same variety over many generations of self pollination

Answer 2

True-breeding

Question 3

The crossing of two opposite true-breeding varieties

Answer 3

Hybridization

Question 4

True-breeding parent individuals

Answer 4

P generation

Question 5

The hybrid offspring of the parents

Answer 5

F1 generation

Question 6

The offspring of the F1 hybrids

Answer 6

F2 generation

Question 7

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

Answer 7

Dominant allele

Question 8

An allele whose phenotypic effect is not observed in a heterozygote

Answer 8

Recessive allele

Question 9

The two alleles for a heritable character segregate during gamete formation and end up in different gametes

Answer 9

Law of segregation

Question 10

A diagrammatic device for predicting the allele composition of all offspring resulting from a cross between individuals of known genetic makeup

Answer 10

Punnett square

Question 11

An organism that has a pair of identical alleles for a character

Answer 11

Homozygous

Question 12

An organism that has two different alleles for a gene

Answer 12

Heterozygous

Question 13

An organism’s appearance or observable traits

Answer 13

Phenotype

Question 14

An organism’s genetic makeup

Answer 14

Genotype

Question 15

Breeding an organism with an unknown genotype with a recessive homozygote to determine the genotype of the unknown organism

Answer 15

Testcross

Question 16

An organism that is heterozygous with respect to a single gene of interest. Parents of genotypes AA and aa produce a ________ of genotype Aa

Answer 16

Monohybrid

Question 17

A cross between two organisms that are heterozygous for the character being followed

Answer 17

Monohybrid cross

Question 18

Organisms that are heterozygous for the two characters being followed in the cross (YyRr)

Answer 18

Dihybrids

Question 19

A cross between two organisms that are both heterozygous for both of the characters being followed

Answer 19

Dihybrid cross

Question 20

Each pair of alleles segregates independently of each other pair during gamete formation

Answer 20

Law of independent assortment

Question 21

A rule of probability stating that the probability of two or more independent events occurring together can be determined by ________ their individual probabilities

Answer 21

Multiplication rule

Question 22

The probability that any one of two or more mutually exclusive events will occur is calculated by adding their individual probabilities

Answer 22

Addition rule

Question 23

When the phenotypes of the heterozygote and the dominant homozygote are indistinguishable

Answer 23

Complete dominance

Question 24

When neither allele is dominant and the F1 hybrids have a phenotype somewhere between those of the parental varieties

Answer 24

Incomplete dominance

Question 25

The two alleles of each organism affect the phenotype in separate, distinguishable ways

Answer 25

Codominance

Question 26

A genetic disease caused by a recessive allele for a dysfunctional enzyme, leading to the accumulation of certain lipids in the brain. Seizures, blindness, and degeneration of motor and mental performance usually become manifest a few months after birth

Answer 26

Tay-Sachs disease

Question 27

The ability of a single gene to have multiple affects

Answer 27

Pleiotrophy

Question 28

When the phenotypic expression of a gene at one locus alters that of a gene at a second locus

Answer 28

Epistasis

Question 29

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

Answer 29

Quantitative characters

Question 30

The additive affect of two or more genes on a single phenotypic character

Answer 30

Polygenic inheritance

Question 31

Referring to a phenotypic character that is influenced by multiple genes and environmental factors

Answer 31

Multifactoral

Question 32

The traits of parents and children across generations

Answer 32

Pedigree

Question 33

Heterozygotes that transmit the recessive allele to their offspring

Answer 33

Carriers

Question 34

A human genetic disorder caused by a recessive allele for a chloride channel protein; characterized as an excessive secretion of mucus and consequent vulnerability to infection

Answer 34

Cystic fibrosis

Question 35

A recessively inherited human blood disorder in which a single nucleotide change in the B-glob in gene causes hemoglobin to aggregate, changing red blood cell shape and causing multiple symptoms in afflicted individuals

Answer 35

Sickle-cell disease

Question 36

A human genetic disease caused by a dominant allele; characterized by uncontrollable body movements and degeneration of the nervous system

Answer 36

Huntington's disease