A(n) is a molecule, cell, or organ that directly carries out a response to a stimulus and restores homeostasis.

What causes the force that pushes magma from the magma chamber through the pipe and vent of a volcano?

Which of the following is an effect of the uneven heating of the earth by the sun? a sea breeze a land breeze a convection current all of the above

The breakdown of food is accomplished by enzymes. a. physical b. chemical c. mechanical d. none of the above