In one day, a zebra eats 10 kg of grass. a lion kills and eats the zebra. about how much of the energy contained originally in the grass is usable by the lion? a.) 0.1 kg b) 10 kg c.) 5 kg d.) 1 kg

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.