Answer:
Iodine
Explanation:
Iodine is needed by animals because the body's metabolic rate is controlled by the action of an iodine hormone, called thyroxine, which is secreted by the thyroid gland in the neck.
If the animal fails to supply enough iodine through food to be able to make a normal amount of this compound, then the thyroid gland enlarges or expands trying to create enough, resulting in a common type of goiter.
Actually, heavier objects fall faster. The difference is infinitesimal, but there is a tiny difference because more mass causes objects to fall faster (e.g. objects fall faster on earth than on the moon). On earth, the different rate of fall between heavier and lighter objects is negligible (because objects are tiny compared to the earth's mass), so objects of different weights fall at virtually the same rate. But not at exactly the same rate. Objects of different weights must accelerate at different rates because accel.
Oxygen and Hydrogen Atoms!
Answer:
B is most likely used for reproduction.
