What is the effect of DNA copying, which is not perfectly accurate, on the reproduction process? How does the amount of DNA remain constant though each new generation is a combination of DNA copies of two individuals?

How can you grow money plant bv vegetative propagation?

State the advantages of sexual reproduction over asexual reproduction.

List six specific characteristics of sexual reproduction.

What are sexually transmitted diseases. List two example of each diseases caused due to,

1. Bacterial infection.
2. Viral infection.

Which device or devices may be used to prevent the spread of such diseases.

Explain budding in Hydra with the help of diagrams only.

1. Write the names of those parts of a flower which serve the same function as the following do in the animals:

1. Testis.
2. Sperm.
3. Ovary.
4. Egg.

2. State the function of flowers in the flowering plants.

Draw a neat diagram of a flower showing its various parts. In this diagram mark stem, receptacle, sepals, petals, stamen and carpel.

1. Explain the terms:

1. Implantation.
2. Placenta.

2. What is the average duration of human pregnancy?

Describe the grafting method for the artificial propagation of plants with the help of labelled diagrams.