Genetics questions | form four Biology

The offspring of two AB blood group parents will possibly be

1. group AB only
2. half of group A, half of group B
3. half of group AB, half of group A
4. of group A,AB and B

In the plant Rosa alba, a pure breed white flowered plant was crossed to a pure breed red flowered plant. All F1 plants had pink flowers. When the pink flowered plants were selfed, offspring in F2 had 102 plants with red flowers , 207 plants with pink flowers and 101 plants with white flower:..
(a) Draw genetic diagrams to show all the eros es involved.
(b) Why were the pink flowered plants produced?

The offspring of crosses between round rooted and long-rooted raddishes were always found to be oval shaped. This is an example of

1. crossing over
2. incomplete dominance
3. mutation
4. recessiveness

Two gray cats are crossed . The female gives birth to 5 gray and 3 black kittens. Which of the following is most probably true?

1. Gray colour is dominant to Black
2. Black colour is dominant to Gray
3. Black and Gray are codominant
4. Colour trait in cats is sex linked

During blood transfusion, a person receiving blood can only accept blood of the correct type. Copy the table below and put inthe box space  a tick if the donor`s blood is compatible with the recipient`s blood and put a cross(X) if the donor`s blood is incompatible with the recipient`s blood.

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.

Distinguish between test-cross and back-cross.

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

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

Give three differences between DNA and RNA.