The organisms A, B and C can obtain their food in three different ways. Organism A derives its food from the body of another living organism which is called its D, without killing it. The organism B takes in the solid food by the process of ingestion, digests a part of this food and throws out undigested food in the process called E. The organism C obtains its food from dead and decaying plants.

1. What is the mode of nutrition of (i) organism A (ii) organism B, and (iii) organism C?
2. What is the organism like D called?
3. Name the process E.
4. Give one example each of organisms like A, B and C.
5. What is the general name of three modes of nutrition exhibited by organisms A, B and C?

Describe the working of human blood circulatory system with the help of a suitable diagram which shows all the steps involved.

With a schematic diagram, explain the overall process of respiration in animals.

Valves are present in between the auricles and ventricles of the heart. Give one reason.

How is double circulation different from single circulation?

Write the difference between nutrition in plants and animals.

What are the methods used by plants to get rid of their waste products?

1. A gas is released during photosynthesis. Name the gas and also state the way by which the gas is evolved.
2. What are stomata? What governs the opening and closing of stomata?

Plants absorb water from the soil. How does this water reach to the top of the tree? Explain in detail.