genetics 2

Question 1

Variations on Mendelian genetics with one gene
Alleles not completely dominant/recessive
Gene with more than two alleles
Gene produces multiple phenotypes

Answer 1

Variations on Mendelian genetics with one gene
Alleles not completely dominant/recessive
Gene with more than two alleles
Gene produces multiple phenotypes

Question 2

Complete dominance(seed form)- 
phenotypes of heterozygote and dominant homozygote identical 
Incomplete dominance- phenotype of heterozygote intermediate 
the dominant allele is not completely express when the recessive allele is around
Codominance- two dominant alleles affect phenotype in separate, distinguishable ways

Answer 2

Complete dominance-
phenotypes of heterozygote and dominant homozygote identical
Incomplete dominance- phenotype of heterozygote intermediate
the dominant allele is not completely express when the recessive allele is around
Codominance- two dominant alleles affect phenotype in separate, distinguishable ways

Question 3

Codominance:
both trait show up
\_\_\_\_\_\_
•RR= red cow hairs 
•RW= red and white cow hairs 
•WW= white cow hairs 
•Erminette chickens 
•BB= black feathers 
•BW= black and white feathers 
•WW= white feathers

Answer 3

Codominance:
both trait show up
Roan cows 
•RR= red cow hairs 
•RW= red and white cow hairs 
•WW= white cow hairs 
•Erminette chickens 
•BB= black feathers 
•BW= black and white feathers 
•WW= white feathers

Question 4

polygenic gene:
Polygenic inheritance- additive effect of two or more genes on single phenotype
many gene affect one trait
example:
eyecolor
height

Answer 4

polygenic gene:
Polygenic inheritance- additive effect of two or more genes on single phenotype
many gene affect one trait
example:
eyecolor
height

Question 5

epistasis:
multifactorial traits
gene at one locus alters phenotypic expression of gene at second locus
eg: fur color
Coat color (one gene= pigment, second gene= whether pigment is deposited)

Answer 5

epistasis:
multifactorial traits
gene at one locus alters phenotypic expression of gene at second locus
eg: fur color
Coat color (one gene= pigment, second gene= whether pigment is deposited)

Question 6

multifactorial trait:
Multifactorial traits- traits depend on multiple genes combined with environmental influences
eg: cancer

Answer 6

multifactorial trait:
Multifactorial traits- traits depend on multiple genes combined with environmental influences
eg: cancer

Question 7

sex-linked trait:
Sometimes genes are found only on X (usually) or Y chromosome •______ •Orange coat gene in cats •Females compensate with X inactivation (random in non-marsupial mammals)

Answer 7

sex-linked trait:
Sometimes genes are found only on X (usually) or Y chromosome •Hemophilia •Orange coat gene in cats •Females compensate with X inactivation (random in non-marsupial mammals)

Question 8

common recessive disease:
_______, sickle-cell anemia
carriers have recessive allele but the normal phenotype

Answer 8

common recessive disease:
cystic fibrosis, sickle-cell anemia
carriers have recessive allele but the normal phenotype

Question 9

dominant disorders:
dominant disorders are rare, arsie by mutation
eg: Huntington’s disease
dominant are not common

Answer 9

dominant disorders:
dominant disorders are rare, arsie by mutation
eg: Huntington’s disease
dominant are not common

Question 10

Polygenic inheritance is the additive effect of two or more genes on single ____________ (e.g. skin color)

Answer 10

Polygenic inheritance is the additive effect of two or more genes on single phenotype (e.g. skin color)

Question 11

____________ is when a gene influences multiple phenotypic traits (e.g. _______).

Answer 11

pleiotropy is when a gene influences multiple phenotypic traits (e.g. cystic fibrosis). mucus buildup in organs, abnormal nutrient absorption

Question 12

Many genetic disorders are rare and caused by recessive alleles. The chance of mating between ____________ increases for relatives (e.g. albinism).

Answer 12

Many genetic disorders are rare and caused by recessive alleles. The chance of mating between relatives increases for disease (e.g. albinism)

Question 13

Polygenic inheritance is the additive effect of two or more genes on single ____________ (e.g. _____)

Answer 13

Polygenic inheritance is the additive effect of two or more genes on single phenotype (e.g. skin color)

Question 14

Multifactorial traits depend on _______ combined with _____ influences (e.g. _____)

Answer 14

Multifactorial traits depend on multiple genes combined with environment influences (e.g. cancer).

Question 15

Many genetic disorders are rare and caused by recessive alleles. The chance of mating between ____________ increases for relatives (e.g.).

Answer 15

Many genetic disorders are rare and caused by recessive alleles. The chance of mating between relatives increases for disease (e.g. albinism)白化病

Question 16

____________ genetic disorders are rare (e.g. Achondroplasia dwarfism) and lethal disorders are likely to show late onset symptoms (e.g. ______)

Answer 16

dominant genetic disorders are rare (e.g. Achondroplasia dwarfism) and lethal disorders are likely to show late onset symptoms (e.g. Huntington’s)