In the stomach lining, neighboring cells must communicate in order to release chemicals in a coordinated way. It is also important that those chemicals not leak between cells and into surrounding tissues. These cells are MOST LIKELY held together by _________.

The smallest level of organization considered alive is _________.

_______ is a system primarily responsible for protection.

Which of these is NOT an exchange system?

Which of these is NOT one of the four major elements found in the human body?

Which of these will alter the activity of an enzyme?

BONUS: Horizontal shoots that grow along the surface and give rise to new plant shoots are called [BLANK-1].

The maintenance of normal muscle tone and the coordination of multiple muscles is the job of the ___________.

Osteoporosis is a condition that results in reduced bone density due to low blood calcium levels. The reduced bone density is due to excess release of ____________.

Which of these does NOT have to be maintained at a constant level in the human body?