10a

Question 1

Incomplete dominance

Answer 1

Mode of inheritance in which a heterozygote’s phenotype is intermediate between the phenotypes of the two homozygotes. (snapdragon color)

Question 2

Codominance

Answer 2

Mode of inheritance in which two alleles are fully expressed in the heterozygote (blood type)

Question 3

Mendel’s Law of segregation (2)

Answer 3

Diploid cells have pairs of genes on pairs of homologous chromosomes. The two genes are separated during meiosis and end up in different gametes.

Question 4

Mendel’s 2nd law

Answer 4

A gene is distributed into a gamete independently of how other genes are distributed.

Question 5

linkage group

Answer 5

Group of genes that tend to be inherited together because they are on the same chromosome

Question 6

Linked genes

Answer 6

genes on the same chromosome

Question 7

linkage map

Answer 7

diagram of gene order and spacing on a chromosome, based on crossover frequencies

Question 8

Product rule

Answer 8

States that the chance that two independent events will occur equals the product of the individual chances that each event will occur.

Question 9

True breeding

Answer 9

Always producing offspring identical to the parent for one or more traits (homozygous)

Question 10

Locus

Answer 10

The physical locatioin of a gene on a chromosome

Question 11

Allele

Answer 11

One of the alternative forms of a specific gene

Question 12

Hybrid

Answer 12

Producing a mix of offspring for one or more traits (heterozygous)

Question 13

Mutant

Answer 13

A phenotype, genotype or allele resulting from a mutation in a gene

Question 14

Dominant allele

Answer 14

An allele that exerts its effects whenever it is present

Question 15

Recessive Allele

Answer 15

An allele whose effect is masked if a dominant allele is also present

Question 16

Test cross

Answer 16

A mating between and individual of unknown genotype and a homozygous recessive individual. The genotype of the unknown parent can be deduced from the phenotype ratio of the offspring.

Question 17

Polygenic

Answer 17

Phenotype reflects the activity of more than one gene. (i.e. eye color)

Question 18

Homozygous

Answer 18

Possessing two identical alleles for a gene

Question 19

Heterozygous

Answer 19

Possessing two different alleles for a gene

Question 20

Autosomnal Dominant

Answer 20

Inheritance pattern of a dominant allele on a chromosome. Expressed in heterzygotes, One or both parents must also have the disorder. (Huntington’s)

Question 21

Autosomnal Recessive

Answer 21

Inheritance pattern of a recessive allele on a chromosome - requires that a recessive allele by passed down by both parents. (albinism)

Question 22

X-inactivation

Answer 22

Turning off all but one X chromosome in each cell of a mammal (usually female) in early development.

Question 23

X-linked

Answer 23

Describes traits controlled by genes of the X chromosome

Question 24

Pleiotropy

Answer 24

One gene has multiple effects on the phenotype. (i.e. one protein is used or affects
many parts of the body. (Marfan/connective tissue)

Question 25

Epistasis

Answer 25

One gene masks another gene’s expression (i.e. baldness hides the effects of a widow’s peak)

Question 26

Phenotype

Answer 26

Observable characteristic of an organism

Question 27

Genotype

Answer 27

An individual’s combination of alleles for a particular gene

Question 28

What is P, F1, F2

Answer 28

The P generation is the parental or starting generation. F1 and F2 (filial) refer to the first and second generations, respectively.

Question 29

What is a monohybrid cross, and what are the genotypic and phenotypic ratios expected in the offspring of the cross?

Answer 29

A monohybrid cross is a mating between two individuals that are each heterozygous for one gene. The genotypic ratio expected in a monohybrid cross is 1:2:1 (homozygous dominant : heterozygous : homozygous recessive); the phenotypic ratio is 3:1 (dominant:recessive).

Question 30

What is a dihybrid cross, and what is the phenotypic ratio expected in the offspring of the cross?

Answer 30

In a dihybrid cross, two individuals that are each heterozygous for two genes are mated. The phenotypic ratio that is expected is 9:3:3:1 (dominant for both genes: dominant for one gene and recessive for the other: recessive for one gene and dominant for the other: recessive for both genes).

Question 31

Punnett square use?

Answer 31

Punnett squares show the genotypes of each parent as well as the genotypes of potential offspring. Phenotypic and genotypic ratios of offspring can be predicted from the data in Punnett squares.

Question 32

X-linked dominant disorders

Answer 32

hairy, rickets, retinis pigmentosa

Question 33

X-linked recessive disorders

Answer 33

RG colorblindness, hemophilia, Duchenne

Question 34

Centromeres divide in?

Answer 34

Mitosis/anaphase and Meiosis 2/Anaphase 2

Question 35

Describe and differentiate between Diploid vs. Haploid

Answer 35

A diploid cell (2n) has two full sets of chromosomes, with one set coming from each parent. A haploid cell (n) has only one set of chromosomes.

Question 36

Non-mendelian inheritance

Answer 36

Codominance, incomplete dominance, pleiotropy, epistasis