The quality of earwax is also an autosomal dominant trait. It is an innocuous phenotype that has two forms. There is wet, sticky earwax and dry earwax. Wet earwax is a result of a single dominant gene (WW or Ww). Dry earwax is from the result of ww combination. Wet earwax is more common in Caucasians and people of African origin (80-90% wet earwax). Dry earwax is more common in Asians (94% dry earwax). A widow’s peak is not dependent on ethnic background but rather dominant in all populations (PP or Pp) while no widow’s peak is recessive. a) Based on this information, create a  Punnett square where a Caucasian male, with no widow’s peak and wet earwax (WW), mates with an Asian female with dry earwax who is heterozygous for a widow’s peak. Give the possible phenotypes.  b) If the F1 generation PpWw then mates with an individual who has no widow’s peak and has dry earwax, give the Punnett square, and genotypic and phenotypic ratios. (I, 5 marks)

In tomato plants, let R = round-shaped tomatoes, r = pear-shaped tomatoes, T = tall vines, t = short vines. A tomato plant with short vines and round fruit has which possible genotypes?

In the formation of gametes by a hybrid individual of genotype Bb, the allele B will go to one gamete, and the allele b will go to a different gamete. This illustrates Mendel’s law of

Centromeres hold duplicated chromosomes together

    Karyotype diagrams are commonly used as a diagnostic tool for which of the following?

An individual carrying two different alleles for a particular trait is known as

After the process of meiosis, the resulting gametes can best be described as

If a woman is a carrier for sex-linked colour blindness, under what conditions can she have a colour-blind daughter?

The series of involuntary muscular contractions by which food moves through the digestive tract is called:

Which of the following is true for homologous chromosomes?