Classify each of the following as a stimulus or a response a. the recess bell ringing in an elementary school

b. your mouth watering at the sight of food on a plate

c. a sudden drop in air temperature

d. a flu virus entering your body

e. getting “butterflies” in your stomach before giving a speech

Calvin ate a candy bar, which caused his body's blood glucose levels to become unbalanced. his body responded by initiating a feedback mechanism to return his body to homeostasis. place the steps of this feedback mechanism in order, starting with the blood glucose imbalance that occurred after calvin consumed the candy bar. a) calvin's blood glucose levels decreased. b) calvin's pancreas stopped secreting insulin. c) calvin's body cells started to take up glucose and store it as glycogen. d) calvin's blood glucose levels increased. e) calvin's pancreas started secreting insulin.

Which of the following sex and generation combinations directly produces the pollen tube of angiosperms? a) male gametophyteb) female gametophytec) male sporophyted) female sporophyte

!if we removed the wolf, snake, and hawk from this food web, what best explains the impact it would have? a) the number of producers would increase. b)the number of decomposers would increase. c)the number of primary consumers would increase. d)the numbers of primary consumers would decrease.