Genetics questions | form four Biology

Sickle cell anaemia is an inherited disease of humans. The disease is controlled by a single pair of alleles. People homozygous for recessive allele develop the disease, while heterozygous do not suffer from it.

1. Using the symbol (A) for dominant allele and (a) for recessive allele, write down the possible genotypes of the following 

1. people who suffer from the disease
2. people who do not suffer from the disease

2. If a homozygous normal male marries a woman suffering from the disease, write down the ratio of children suffering: children not suffering in the F2 Generation.

Answer / Solution

UNSOLVED

Distinguish between test-cross and back-cross.

Answer / Solution

UNSOLVED

The chromosomes for two sexes in human beings are

1. female YY and male XY
2. female XY and male XX
3. female XX and male YY
4. female XX and male XY
5. female X and male Y

Answer / Solution

UNSOLVED

Write down the components of the DNA (Deoxyribo-Nucleic-Acid)

Answer / Solution

UNSOLVED

Give three differences between DNA and RNA.

Answer / Solution

UNSOLVED