State any one difference between autotrophic and heterotrophic modes of nutrition.

How is the small intestine designed to absorb digested food?

In the following questions, a statement of Assertion is given followed by a statement of Reason. Mark the correct answer as:
Assertion: Nutrition in $Amoeba$ takes place with the help of $pseudopodia$.
Reason: Different stages of nutrition in $Amoeba$ are ingestion, digestion, absorption, and egestion.

Name the enzyme present in human saliva. What type of food material is digested by this enzyme?

What will happen to the rate of photosynthesis in a plant under the following circumstances?
$(i)$ Cloudy day in the morning but bright sunshine in the afternoon.
(ii) No rainfall in the area for a considerable time.
(iii) Gathering of dust on the leaves.

Explain the process of digestion of food in the mouth, stomach, and small intestine in the human body.