Classical Genetics

Question 1

What are the different types of genetics?

Answer 1

Molecular genetics
Population genetics
Classical genetics

Question 2

What are the different types of genetic crosses?

Answer 2

Establishing dominance
Test cross
Reciprocal cross
Dihybrid self-cross
Dihybrid test cross

Question 3

What is establishing dominance?

Answer 3

Cross two pure-breeding strains
F1 will have the phenotype of the dominant allele
If not, there is allele interaction

Question 4

What is a test cross?

Answer 4

Cross the organism with the dominant phenotype to a recessive tester
Either all dominant phenotypes or a mix of dominant and recessive

Question 5

What is a reciprocal cross?

Answer 5

Cross strain A and strain B in both directions
F1 results will be the same
If not then the gene is on a sex chromosome

Question 6

What is a dihybrid self-cross?

Answer 6

Cross a homozygous dominant and recessive together
Self-cross the F1
Will result in a 9:3:3:1 phenotype ratio
If not then there is gene interaction

Question 7

What is a dihybrid test cross?

Answer 7

Cross a dominant phenotype with an unknown recessive tester to determine the genotype
F2 will have a 1:1:1:1 phenotype ratio
If not then the genes are on the same chromosome

Question 8

What is the multiplication rule?

Answer 8

The probability that two events both occur is equal to the probability that one event occurs times the probability that the other event occurs

Question 9

What is the addition rule?

Answer 9

The probability that either of two events occurs is equal to the probability that one event occurs plus the probability that the other event occurs

Question 10

What is the subtraction rule?

Answer 10

Either something will happen or it won’t

Question 11

What is a gambler’s fallacy?

Answer 11

Past events influence future probabilities

If something hasn’t come up recently it is more likely to now