Draw a neat labelled diagram of the human excretory system.

How are fats digested in our bodies? Where does this process take place?

Draw the diagram of alimentary canal of man and label the following parts.Mouth, Oesophagus, Stomach, Intestine.

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

Describe the mechanism of urine formation in human excretory system. Draw a labelled diagram to illustrate your answer.

How do carbohydrates, proteins and fats get digested in human beings?

1. Draw the structure of a nephron and label the following on it: Glomerulus, Bowman’s capsule, Renal artery, Collecting duct.
2. What happens to glucose that enters the nephron along with filtrate?

Some sugar solution is taken in a test-tube and a little of substance X in powder form is added to it. The mouth of test - tube is closed with a cork and allowed to stand for sometime. On opening the cork, a characteristic smell of substance Y is obtained and a gas Z is also observed to be formed. The gas Z extinguishes a burning matchstick.

1. What could be X, Y and Z?
2. What is the process of converting sugar into substance Y by the action of X known as?
3. What type of respiration is exhibited by X in the above process?

State the location of salivary glands.

The partially digested food coming from the stomach of a person enters a long and narrow organ A in his body. The organ A receives the secretion of two glands: liver and pancreas. Liver secretes a greenish - yellow liquid B which is normally stored in the organ C. Pancreas secretes pancreatic juice which contains three digestive enzymes D, E and F. The intestinal juice completes the process of digestion of food. The inner wall of organ A has millions of tiny finger - like projections G which help in the rapid absorption of digested food into blood stream. The undigested part of food then passes into wider tube H which absorbs most of the water from undigested food. The last part of tube H called I stores this undigested food (or waste) for some time. The undigested food is then passed out though opening J as faeces in the process known as K.

1. Name the organ A.
2. Name liquid B and organ C.
3. What are the digestive enzymes D, E and F?
4. Name the projections G present on the inner wall of organ A.
5. Name Tube H, Part I, Opening J and Process K.