which one of the statements describes an event that takes place during gene regulation at the level of the chromosome?

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.

Agroup of organisms that changes over time is said to

Where is pericardial fulid located