One function of the human excretory system is *
a
Making materials that the body cells need
b
removing excess heat energy from the body
c
moving substance to and from the body cells
d
controlling the body's responses to stimuli

You and a group of friends are spending your vacation hiking through the mountains. it is cold in the mountains. you will be expending a lot of energy while hiking and you will need plenty of energy to keep you warm. you should pack foods high in to provide the most energy or kilocalories per gram of food. a) carbohydrates b) lipids (fats) c) proteins d) sugars