Ivan pavlov, a russian repeatedly exposed dogs to the sight of food and, at the same time, the sound of a at first, the dogs salivated because of the food; this reaction is known as but after a while, the dogs begin to salivate when they heard the sound, even if no food was present. this learned reaction is known as and the sound is called a

Migration is a. the movement of organisms from a native location to a foreign location b. the movement of organisms from a foreign location to a native location the movement of organisms from their water supply to their food supply d. the seasonal movement of organisms between locations c. select the best answer from above

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 do we call an individual that has inherited two identical alleles for the same trait? a.homozygous b.heterozygous c.monozzygous