Select the correct statement.

On which type of food does salivary amylase act in the buccal cavity,and what is the name of the initial product formed due to the action of this enzyme?

$(a)$ State the reason for the following:
$(i)$ Herbivores need a longer small intestine,while carnivores have a shorter small intestine.
$(ii)$ The lungs in human beings are designed to maximize the area for the exchange of gases.
$(b)$ The rate of breathing in aquatic organisms is much faster than that seen in terrestrial organisms.

How do desert plants perform the photosynthesis process even though their stomata remain closed during the daytime?

During respiration,the exchange of gases takes place in:

What are the factors needed for maintaining the direction of diffusion in plants?