Mendelian Inheritance II

Question 1

when does inheritance of a single gene deviate from mendels laws

Answer 1

when ptypes of alleles are not completely dominant or recess
when a gene has > 2 alleles (multiple alleles)
when a gene produces multiple ptypes (pleiotropy)

Question 2

incomplete dominance

Answer 2

offspring has intermediate ptype of parents

ex. white flower plus red flower = pink

Question 3

codominance

Answer 3

both ptypes of each allele expressed

Question 4

what is a disease that displays multiple layers of ptypes

Answer 4

Tay Sachs

Question 5

at organismal level… tay sachs is

Answer 5

recessive

Question 6

at the biochemical level, Tay Sachs is…

Answer 6

incompletely dominant

Question 7

at molecular levle, Tay Sachs is

Answer 7

codominant

Question 8

dominant human disorders

Answer 8

Huntingtons, achondroplasia, polydactyl

Question 9

multiple alleles

Answer 9

ABO blood group

codominant ptype

Question 10

pleiotropic

Answer 10

most genes
causes multiple ptypes
ex. sickle cell causes kidney and heart failure, paralysis, weakness and fatigue

Question 11

define quantitative characters

Answer 11

vary along a continuum

indicates polygenic inheritance

Question 12

polygenic inheritance

Answer 12

additive effect of 2 or more genes on a single ptype

many genes contributing to one ptype that is additive, ex. skin color

Question 13

epistasis

Answer 13

gene at one locus changes ptypic expression of a gene at second locus
ex dog coat color…one gene is black or brown color other gene determines whether pigment will be deposited or not