Genetic analysis

Question 1

law of segregationn

Answer 1

two alleles for each gene separate during gamete formation

Question 2

law of independent assortment

Answer 2

alleles of genes on nonhomologous chromosomes assort independently during gametes

Question 3

different alleles of the same gene always

Answer 3

segregate independently during meiosis

Question 4

phenomenon of independent assortment reflects the behavior

Answer 4

alleles of genes that are located on different chromosomes

Question 5

Gene

Answer 5

the DNA sequence required to synthesize a product important for the function of a cell

Question 6

Allele

Answer 6

A copy of a gene. Diploids have two alleles of each gene. These alleles can be the same or different

Question 7

Variant

Answer 7

a specific version of the DNA of a gene

Question 8

locus

Answer 8

The physical location on the chromosomes of a gene.

Question 9

How many locus do each gene have in a diploid genome?

Answer 9

one

Question 10

null mutation

Answer 10

no protein made at all

Question 11

weak mutation

Answer 11

encoded mutated protein works but not as well

Question 12

conditional mutation

Answer 12

under some condition, the mutated encoded protein doesn’t work when the wild type protein does

Question 13

gain-of-function mutation

Answer 13

encoded protein works differently and more than wild type (always on)

Question 14

Why are alleles recessive?

Answer 14

usually because they are loss of function mutations

Question 15

What is the phenotype of heterozygote of?

Answer 15

functional protein

Question 16

Tyrosinase

Answer 16

catalyzes the first step in melanin production

Question 17

Example of conditional allele in tyrosinase gene

Answer 17

temperature-sensitive mutation

Question 18

temperature sensitive mutation

Answer 18

different colors concentrated on certain body parts away from heat

Question 19

incomplete dominance

Answer 19

occurs when 50% of gene product is not sufficient full function

Question 20

co-dominance

Answer 20

both alleles are visible

Question 21

3/4 of the progeny of the F2 progeny of a plant heterozygous for the P (purple) and p (white) alleles have purple flowers. What fraction of the purple plants will produce progeny with white flowers by a self cross

Answer 21

2/3

Question 22

epistasis

Answer 22

two unlinked loci(genes) ‘interact’

Question 23

Summarize epistasis

Answer 23

mutation at one locus/gene influences a second locus/gene

Question 24

Name human diseases whose genetic contribution is polygenic (5)

Answer 24

1. hypertension
2. Type 1 and 2 diabetes
3. schizophrenia
4. inflammatory bowel disease
5. asthma

Question 25

quantitative variation in humans

Answer 25

distributed around mean

Question 26

environmental impact

Answer 26

influences phenotypes of gene alleles

Question 27

Genome-wide association studies

Answer 27

studies human genetics of complex traits

Question 28

effect of snp

Answer 28

particular snp more or less frequent in affected individuals than in unaffected individuals

Question 29

multifactorial traits

Answer 29

polygenic and environment plays a role