2.3 Monohybrid and Dihybrid Crossing Part 2

Question 1

What is a test cross?

Answer 1

when an individual that has a dominant phenotype but unknown genotype is crossed with a known homozygous recessive individual

Question 2

What is a dihybrid cross?

Answer 2

looking at two characteristics simultaneously

Question 3

How many different possible combinations are there in a dihybrid cross?

Answer 3

16

Question 4

What is Mendel’s 9:3:3:1 dihybrid ratio?

Answer 4

states that every F1 x F1 crossing will result in this ratio of offspring

Question 5

What is Mendel’s fourth postulate?

Answer 5

during gamete formation, segregating pairs of unit factors assort independently of each other

Question 6

What does the product law of probabilities state?

Answer 6

the probability of two or more independent events occuring simultaneously is equal to the product of their individual probabilities

Question 7

What methods can be used to easily calculate the probabilities of inheriting any combination of traits?

Answer 7

fork line method
branch diagram

Question 8

In what case does the product law not apply?

Answer 8

when genes do not assort with complete independence