Pseudorumination is

Vitamin $A$ is synthesized from carotene in the ...... .

Which of the following will release more energy on oxidation? Arrange them in ascending order.
$(a)$ $1 \; g$ of fat
$(b)$ $1 \; g$ of protein
$(c)$ $1 \; g$ of glucose
$(d)$ $0.5 \; g$ of protein $+ 0.5 \; g$ of glucose

Given below are two statements:
$Statement I$: The cardiac sphincter prevents regurgitation of food from the stomach to the duodenum.
$Statement II$: The pyloric sphincter regulates the flow of food from the oesophagus to the stomach.
In the light of the above two statements, choose the most appropriate answer from the options given below.

Which one of the following vitamins can be synthesized by bacteria inside the gut?

State the function of saliva.