Answer to Question 1
B
Explanation: A) The pineal gland does not directly regulate many other endocrine glands.
B) Correct. The pituitary is the master gland because it directly regulates so many other endocrine glands.
C) The hypothalamus does not directly regulate many other endocrine glands.
D) The gonads do not directly regulate many other endocrine glands.
Answer to Question 2
B
Explanation: A) Veins return blood to the heart.
B) Correct.
C) Capillaries are the smallest vessels between the arteries and veins.
D) The atria are the upper chambers of the heart.