Questions

Alternative (a) refers to a delta

Eating raises blood sugar levels, insulin stimulates the lowering of blood sugar level. In this example the response to the stimulus (increased blood sugar levels) opposes that stimulus (by lowering blood sugar levels).

Trees that lose all of their leaves for part of the year are known as deciduous trees. Those that don't are called evergreen trees.

When hierarchical routing is used, the routers are divided into what we call regions, with each router knowing all the details about how to route packets to destinations within its own region, but knowing nothing about the internal structure of other regions

A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This allows for faster reflex actions to occur by activating spinal motor neurons without the delay of routing signals through the brain.

An orthodontist is the type of doctor that specializes in teeth and jaw alignment. When the teeth don't align properly, it can cause uneven wear in the teeth.

The jaw is a hinge joint. Strong muscles in the face open and close the jaw. Teeth are implanted in the jaw and serve to rip, tear and crush food in preparation for swallowing it.