Mendelian Inheritance cont.

Question 1

Probability

Answer 1

ratio of # of times a particular event is expected to happen to the # of trials during which the event could have happened

Question 2

Product Rule

Answer 2

states that the probability (P) of two independent events occurring simultaneously is the product of their individual probabilities; “and”

Ex: What is the P of getting heads by flipping the coin twice?

P(H & H) = 1/4
P(T & T) = 1/4
P(H & T) = 1/4
P(T & H) = 1/4

Question 3

Sum Rule

Answer 3

the probability of several mutually exclusive events occurring, is the sum of their individual probabilities (non-simultaneous); “or”

Ex: What is the P of getting different faces of the coin when tossing a coin twice?

P(different faces) = P(HT) + P(TH) = (1/2 x 1/2) + (1/2 x 1/2) = 1/4 + 1/4 = 1/2

Question 4

F2 progeny

Answer 4

can be classified as parental and non-parental or recombinant types

Question 5

Parental type

Answer 5

have same alleles as the gametes that formed the F1 (S and Y; s and y)

Question 6

Recombinant type

Answer 6

have different combination of alleles from those in the gametes that formed the F1 (Y and s; y and S)

Question 7

How to determine if the genotype is homozygous dominant or heterozygous?

Answer 7

Do a testcross with a homozygous dominant/heterozygous w/ a homozygous recessive genotype.

Question 8

What are the number of gametes in P1 (Aa Bb Cc Dd)?

Answer 8

2 x 2 x 2 x 2 = 16 (1 gamete per diff. allele)

Question 9

What are the number of gametes in P2 (aa Bb Cc DD)?

Answer 9

1 x 2 x 2 x 1 = 4

Question 10

What are the # of genotypes in F1?
(P1: Aa Bb Cc Dd and P2: aa Bb Cc DD)

Answer 10

2 x 3 x 3 x 2 = 36

Question 11

What are the # of phenotypes in F1?
(P1: Aa Bb Cc Dd and P2: aa Bb Cc DD)

Answer 11

2 x 2 x 2 x 1 = 8

Question 12

Pedigrees

Answer 12

analysis of inheritance of families; typically small number of offspring; allows inferences concerning genotypes and predictions concerning phenotypes of offspring (genetic counseling); pedigree data is displayed using symbols to represent various individuals, matings, and offspring

Question 13

What does a square and a circle mean on a pedigree chart?

Answer 13

Square = male
Circle = female

Question 14

What is a shaded shape mean on a pedigree chart?

Answer 14

Affected individuals

Question 15

What are some examples of autosomal recessive diseases?

Answer 15

PKU, Tay-Sachs, albinism

Question 16

What are some examples of autosomal dominant diseases?

Answer 16

Huntington’s disease, achondroplasia

Question 17

What are some examples of X-linked recessive diseases?

Answer 17

color-blindness, hemophilia

Question 18

What are some examples of X-linked dominant diseases?

Answer 18

hypophosphatemia

Question 19

Wild type

Answer 19

the genotype or the phenotype that is found in nature or a standard laboratory stock in a given organism

Question 20

Mutant

Answer 20

an organism or cell carrying a mutation

Question 21

Mutant allele

Answer 21

an allele differing from the allele found in the standard, or the wild type

Question 22

Autosomal recessive

Answer 22

usually skips a generation or generations; males and females are both affected; if the parents of an affected individual do not exhibit the trait, then they are a carrier

Question 23

Autosomal dominant (rare)

Answer 23

usually does not skip a generation; both males and females are affected; the abnormal (mutant) allele is dominant

Question 24

What is the genotype of a male?

Answer 24

XY

Question 25

What is the genotype of a female?

Answer 25

XX

Question 26

What is the specific region of pairing called for sex chromosomes?

Answer 26

pseduoautosomal regions

Question 27

Which sex can be a carrier of a recessive trait?

Answer 27

Female (XX); homogametic sex

Question 28

Who is the heterogametic sex?

Answer 28

Male; if carries the gene, will express the recessive trait or phenotype