How is double circulation different from single circulation?

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

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

‘Aerobic respiration produces more ATP than anaerobic respiration’. Justify this statement.

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?

Draw a neat labelled diagram of the human excretory system.

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?

Explain the principle of dialysis with the help of a labelled diagram.

1. Draw a diagram of human alimentary canal and label - gall bladder, pancreas, liver and small intestine on it.
2. Give two reasons to explain why absorption of digested food occurs mainly in the small intestine.

Draw a labelled diagram of the human digestive system. With the help of this diagram, describe the process of digestion of food in man (humans).