Placing a rat in a cage where electrical shocks over which the rat has no control are occasionally administered through the floor is a way to create

The illustration shown is an ovum, a female sex cell. a mutation in this cell may be passed to the woman’s offspring during a) birth. b) mitosis. c) dna replication. d) sexual reproduction

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.

What could happen if two base pairs on a strand of dna or switched