Sex chromosomes and dosage

Question 1

incomplete dominance

Answer 1

heterozygote has phenotype that is intermediate between that of homozygotes

Question 2

co-dominance

Answer 2

different alleles give qualitatively different dominant traits and you see both traits in heterozygotes at the same time

Question 3

ABO blood types

Answer 3

example of co-dominance; there are different carbs on the blood’s surface and can cause transfusion reactions

Question 4

I gene

Answer 4

the gene that codes for blood type

Question 5

pleiotropy

Answer 5

a single mutation may affect many tissues and processes

Question 6

autosome

Answer 6

non sex chromosomes

Question 7

pseudoautosomal region

Answer 7

region on sex chromosomes that allows homologous pairs to be linked (the coding regions match)

Question 8

SRY gene

Answer 8

in males, encodes a master transcription factor for the creation of testes and testosterone

Question 9

sex linked gene

Answer 9

many genes that are found on X are not found on Y and vice versa

Question 10

hemizygous

Answer 10

half diploid, ex. X and Y do not have the same genes so an XY zygote would only have one of each gene region