The body's ability to maintain a relatively constant internal environment is called homeostasis. this stability can be challenged by:
(select all that apply)
a. reduced water or food intake
b. infectious organisms
c. elevated or depressed blood ph
d. extreme temperatures.

What organ systems are working to you cool down after a workout?

Which of the following best describes the purpose of the parathyroid hormone? a. it decreases the blood calcium level and decreases blood phosphorus level. b. it decreases the blood calcium level and increases the blood phosphorus level. c. it increases the blood calcium level and increases blood phosphorus level. d. it increases the blood calcium level and decreases blood phosphorus level.

Dna replication occurs in preparation for