Which of the following is an autotroph?
$(A)$ Green plant
$(B)$ Man
$(C)$ Fungi
$(D)$ Virus

Amino acids are formed by the decomposition of which component of our diet?

What is the name of the cells in the leaf of a plant that control the opening and closing of stomata?

$(a)$ Draw a diagram of the human alimentary canal and label the following: gall bladder, pancreas, liver, and small intestine.
$(b)$ Give two reasons to explain why the absorption of digested food occurs mainly in the small intestine.

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 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.
$(a)$ What is the mode of nutrition of $(i)$ organism $A$ (ii) organism $B$, and (iii) organism $C$?
$(b)$ What is the organism like $D$ called?
$(c)$ Name the process $E$.
$(d)$ Give one example each of organisms like $A$, $B$ and $C$.
$(e)$ What is the general name of the three modes of nutrition exhibited by organisms $A$, $B$ and $C$?

Represent the equation of photosynthesis. Explain the steps involved in photosynthesis. In which way are the steps of photosynthesis different in desert plants?