Base your answer to the question on the information below and on your knowledge of biology.

a student designed an experiment to determine if the air temperature had an effect on the rate of photosynthesis in corn plants.

the independent variable in this experiment is the:

a) air temperature at which the corn plants were grown

b) amount of carbon dioxide used by the corn plants

c) volume of oxygen produced by the corn plants

d) number of corn plants used

endo:

regulates body hormones, aldosterone, vasopressin

neural:

signal, regulates body using electric signals, reflex

endo has to do with hormones; aldosterone and vasopressin are both hormones. i also had this question and got it right : d

these muscles maintain the blood pressure in the vessels. the smooth muscles are innervated by nerves of the autonomic nervous system. when the muscles contract, they cause vasoconstriction of the vessels and increase blood pressure. when the muscles relax, they enable vasodilation of the   blood vessels hence reduce blood pressure.