Extensions of Mendelian inheritance 3

Question 1

Mendelian Inheritance

Answer 1

Are inheritance patterns that obey the law of segregation & law of independent assortment

Question 2

___________ alleles often cause a reduction in the amount or function of the encoded protein

Answer 2

Recessive allele

Question 3

Wild allele

Answer 3

Alleles in a natural population

Question 4

Mutant Alleles

Answer 4

Random mutations that alter preexisiting alleles

Question 5

_______________ disrupt gene functions & don’t always express a functional gene & they are inherited by a recessive alleles

Answer 5

Random mutations

Question 6

____________ alleles ususally contains a mutation that causes a defect in the synthesis of a protein

Answer 6

Recessive Alleles

Question 7

What are the 3 ways that dominant mutant alleles usually exert their effects?

Answer 7

1. Gain of function
2. Dominant-negative mutations
3. Haploinsufficiency

Question 8

Gain of function mutation

Answer 8

Changes the gene (or protein encodedby a gene) so that it gains an abnormal (new) function (ex. Mutant gene may be overly expressed producing too much encoded proteins)

Question 9

Dominant negative mutations

Answer 9

Changes a protein so that the mutant protein act against the normal protein (Ex. In heterozygote the mutant protein counteracts the effects of the normal protein which alters the phenotype)

Question 10

Haploinsufficiency

Answer 10

Pattern of inheritance where a heterozygote (one which a functioning allele & one with a inactive allele) exhibits an abnormal or disease phenotype (Ex. Having extra fingerings)

Question 11

Traits may skip a generation due to ________________

Answer 11

Incomplete penetrance

Question 12

Incomplete pentrance

Answer 12

When an allele that is expected to cause a particular phenotype doesn’t

Question 13

Expressively

Answer 13

Degree to which the trait is expressed

Question 14

Norms of reaction

Answer 14

Refers to the effects of environmental varation on a phenotype

Question 15

_____________ can affect the phenotype of an individual or species

Answer 15

Environment

Question 16

Incomplete dominance

Answer 16

Occurs when two alleles produce a mixture of the two genotype as its phenotype (intermediate phenotype) (Ex. crossing red & white flowers & getting pink flowers)

Question 17

Overdominance

Answer 17

Occurs when heterozygote have greater reproductive sucess (Ex. Sickle cell disease)

Question 18

Multiple alleles

Answer 18

Genes that found in 3 or more alleles (Ex. The ABO blood groups which determines blood type)

Question 19

Codominance

Answer 19

When two dominant alleless are both expressed

Question 20

Sex - influeneced inhertiance

Answer 20

An allele is dominant in one sex but recessive in the oppsite sex (Ex. Girls have certain traits guys dont)

Question 21

Sex-limited inheritance

Answer 21

Only one sex can inherit a certain trait (Ex. Guys have traits girls dont)

Question 22

Lethal alleles

Answer 22

Alleles that could cause someone to die

Question 23

Conditional lethal alleles

Answer 23

Lethal alleles that could kill someone under certain conditions

Question 24

Semilethal alleles

Answer 24

Act only in certain groups of people

Question 25

Pleiotropy

Answer 25

Occurs when a single gene has multiple effects on a phenotype

Question 26

Gene interaction

Answer 26

When two different genes affect a single trait

Question 27

Gene interaction can exhibit _____________ & _______________

Answer 27

Epistasis & complementation

Question 28

Epistasis

Answer 28

When alleles of one gene masks the phenotype of alleles on another gene at a different location (locus)

Question 29

Complementation

Answer 29

When an offspring is prodcued with a phenotype from parents that have the same or similar recessive phenotype

Question 30

Due to ______________ loss of function alleles may have no effect on a phenotype

Answer 30

Gene Redundancy

Question 31

Gene Redundancy

Answer 31

When one gene can compensate for the loss of function of another gene