theme 4a-mendelian inheritance

Question 1

what is mendels principle of segregation?

Answer 1

1.each organism is diploid (has two alleles)
2.homozygous- same two alleles which produce one type of gamete
3. heterozygous- two allels are different which produce two types of gametes

Question 2

what is a test cross?

Answer 2

mating to an individual with the homozygous recessive genotype (a/a)

Question 3

what isa test cross used for?

Answer 3

to determine whether the dominant phenotype is a homozygote or heterozygote

Question 4

what would you expect if the dominant phenotype is heterozygous in a test cross?

Answer 4

we would see 1:1 of dominant and recessive phenotypes

Question 5

what would we expect if the dominant phenotype was homozygous in a test cross?

Answer 5

we would see all dominant phenotypes

Question 6

what did sutton notice when studying fertilization and meiosis in grasshoppers

Answer 6

-chromosomes occur in pairs in diploid organsims
-chromosomes of each pair sperated in gametes
-seperation of each pair of chromosomes is indpependant of other pairs

Question 7

what are the exceptions to dominant traits masking recessive ones?

Answer 7

incomplete dominance
codominance

Question 8

what is incomplete dominance?

Answer 8

one allele is not completely dominany to the other allele
-intermediate phenotype

Question 9

what is codominance?

Answer 9

codominant alleles have equal effects
-2 distinct pheontypes being expressed at the same time

Question 10

what is polygenic?

Answer 10

multiple genes contibuting to one trait

Question 11

what is blending inheritance?

Answer 11

offspring have traits that are intermediate tot heir parents

Question 12

what is inhetritance of aquired traits?

Answer 12

favourable traits acquired by parents are passed on to offspring

Question 13

what are some issues with blending inheritance?

Answer 13

-variation will be reduced over time
-doesn’t explain why more black bunnies appear
-dilution of traits