W9L2 - Mechanisms of Inheritance

Question 1

Answer 1

Male, female, sex unspecified

Question 2

Answer 2

Affected

Question 3

Answer 3

Carrier

Question 4

Answer 4

Deceased

Question 5

Answer 5

Sex-linked

Question 6

What kind of inheritance is this n y

Answer 6

Autosomal recessive inheritance due to carriers expressing trait

Question 7

What kind of inheritance is this and why

Answer 7

autosomal dominant - one of the parents need to have the trait to express to their kids

Question 8

What are X-linked recessive inheritance

Answer 8

XY males more likely to be affected since females XX have one more X chromosomes, affected males do not have affected sons, some gen skipped, mothers pass trait onto sons

Question 9

What is X-linked dominant inheritance

Answer 9

X chromosome has dominant gene on XY = X chromosome goes to daughter and Y chromosome goes to son hence only daughter gets affected, present in every generation

Question 10

Who do affected mothers with X-linked dominant traits pass to

Answer 10

sons and daughters

Question 11

What is an example of X-linked dominant inheritance

Answer 11

hypertrichosis

Question 12

Who is affected in Y-linked dominant inheritance

Answer 12

ONLY males, passed from father to son every male affected has an affected father

Question 13

What is incomplete dominance

Answer 13

Incomplete dominance is when neither allele is completely dominant, so the heterozygous individual shows a blend of both traits.

Question 14

What is an example of incomplete dominance

Answer 14

red and white snapdragons produce pink snapdragons

Question 15

What is codominance

Answer 15

the phenotype of both alleles are expressed

Question 16

What is an example of codominance

Answer 16

pure white and pure red roans produce a spotted roan

Question 17

What are multiple alleles

Answer 17

A gene that has more than two possible alleles in the population, but each individual still only inherits two

Question 18

What is an example of multiple alleles

Answer 18

Blood types

Question 19

What are polygenic traits

Answer 19

many genes controlling one trait

Question 20

What are examples of polygenic traits

Answer 20

phenotypes that are often continuous such as height, weight, skin colour

Question 21

What is mitochondrial inheritance

Answer 21

Mitochondrial genes are maternally inherited, traits encoded in the mitochondria are only inherited from mothers

Question 22

What is epistasis

Answer 22

Phenotypic expression of a gene at one locus that alters the gene at a second different locus

Question 23

What is an example of epistasis in labradors?

Answer 23

First gene codes for whether the dog will be black or brown, second gene determines whether pigment will be deposited in the hairs

Question 24

What is pleiotropy

Answer 24

Single gene that influences multiple traits or characteristics

Question 25

What is genetic linkage

Answer 25

Alleles located closer more likely to be inherited together more frequently as they are less likely to be separated during meiosis due to genetic recom or crossing over

Question 26

What is nondisjunction

Answer 26

chromosomes do not distribute to the poles as expected in either meiosis I or II resulting gametes contain abnormal no of chromosomes

Question 27

What is aneuploidy

Answer 27

abnormal number of chromosomes in a cell e.g down syndrome

Question 28

Examples of how environment affect gene expression

Answer 28

hydrangeas grown in basic soil are pink, grown in acidic soil are blue