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

A student weighed some raisins and recorded the weight as $x$. She then soaked the raisins in distilled water. After about $2 \text{ hours}$, she removed the raisins, wiped them dry, and weighed them again, recording the weight as $y$. The percentage of water absorbed by the raisins can be determined using the relationship:

What substance is mixed with food in the mouth during chewing by the teeth?

What is the function of enzymes in the human digestive system?

Which of the following organisms exhibits a parasitic mode of nutrition?

When carrying out the starch test on a leaf, why is it important to boil the leaf in alcohol?