Transmission genetics

Question 1

when are reccessive alleles expressed?

Answer 1

If homozygous

Question 2

What is P1, F1, F2

Answer 2

Parental generation, First filial generation, second filial gen

Question 3

What does progeny mean

Answer 3

Offspring

Question 4

advantages of studying pea plant (pisum sativum)

Answer 4

1. different discrete traits can be studied
2. self fertilizer
3. quickly reproduces

Question 5

What’s Mendel’s first postulate? UNIT FACTORS IN PAIRS

Answer 5

One aspect of a trait comes from one parent and another aspect of a trait comes from the other parent

Question 6

What’s Mendel’s second postulate? Dominance/recessive

Answer 6

If two alleles are heterozygous then the dominant one will determine the appearance and the recessive doesn’t have any noticeable effect

Question 7

if crossed Tt and Tt in the F1 gen, what would the F2 gen look like?

Answer 7

1/4 TT
2/4 Tt
1/4 tt

Question 8

Mendel’s third postulate (first law) SEGREGATION

Answer 8

If heterozygous then 50% gametes contain one allele type and 50% the other. If homozygous then alleles identical then so are all the gametes.

Question 9

What’s the phenotypic ratio in F2 MONOHYBRID

Answer 9

3(dominant):1(recessive)

Question 10

Genotypic ratio in complete dominance in F2

Answer 10

1 (Dominant): 2 (heterozygous): 1(recessive)

Question 11

What’s dihybrid inheitance?

Answer 11

2 genes on different chromosomes each with 2 alleles. looking at 2 phenotypes at the same time. in ON

Question 12

Mendels 4th postulate (second law) INDEPENDENT ASSORTMENT

Answer 12

a pair of traits segregates independently of another pair during gamete formation.
different traits get equal opportunity to occur together.

Question 13

What’s the phenotypic ratio in F2 DIHYDRBRID

Answer 13

9(a dominant pheno):3(the otuer dom pheno):3(recessive):1(recessive)

in ON

Question 14

What is incomplete dominance

Answer 14

E.g red flower (RR) and White flower (rr) makes pink Rr instead of just red.

No complete dominance

Question 15

What’s the F2 ratio in incomplete dominance

Answer 15

1:2:1
RR:Rr:rr

Question 16

What blood type can accept blood from any donor? Often referred to as universal recipients

Answer 16

AB

Question 17

What blood type can donate blood to any recipient? Often referred to as universal donors

Answer 17

O

Question 18

Codominance

Answer 18

Includes phenotypes of both homozygous parents.
E.g blood type AB

Question 19

What does a ratio of 2:1 suggest?

Answer 19

Lethality, lost a 1/4 of the offspring

Question 20

What are Dihybrid gene interactions

Answer 20

Two separate genes each with two alleles. They both give a single phenotype together.

Normally would expect a 9:3:3:1 but can get really weird ratios.

Question 21

What’s recessive epistasis

Answer 21

Ratio = 9:3:4

E.g Labrador dogs, can get black brown and yellow

Dominant A allele produces Black, recessive a produces brown, dominant. Dominant B allows the pigment of the colour to show.
in ON