M5: Deviations from Mendel's Ratio's

Question 1

sex determination?

Answer 1

the way which sex chromosomes seperare during meiosis and then recombine during fertilisation. females 22 autosomes + x, males 22 autosomes + y

Question 2

non-disjunction?

Answer 2

When a pair of homologous chromosomes/sister chromatids fail to separate during cell division. eg down syndrome

Question 3

sex linkage?

Answer 3

Sometimes genes on X and Y code for traits other than gender. If a gene occurs on the X chromosome, females will have 2 alleles for the gene, men only one, therefore, men are more frequently.

Question 4

incomplete dominance?

Answer 4

blending of features of two > alleles expressed giving a hybrid that is intermediate. eg red flower plus white flower = pink flower

Question 5

co-dominance?

Answer 5

both are expressed. eg a red bull plus white cow = roan calf