Are specialized cells that conduct impulses through the nervous system.

hey there!

so, when you eat, your teeth chew and grind food into smaller pieces. this is mechanical digestion. then reactions aided by digestive enzymes break down large food molecules into smaller molecules. this is chemical digestion. the two processes change the food into simpler substances that can be used by the body for raw materials and energy.

hope this

tobey

it has one origin of replication, but it proceeds in two directions - d)