Which of these work together in a feedback loop?
A. Insulin and glucagon
B. Pancreas and large intestine
C. Testes and sweat glands
D. Glucose and calcium ions

What type of lipids are found in all biological membranes?

Which of these transport mechanisms moves glucose from the blood into a cell? active transport diffusion facilitated diffusion osmosis

What causes eclipses? check all that apply. earth's rotation on its axis moon's shadow covering the sun earth's shadow covering the moon earth's orbit and moon's orbit occasionally aligning the moon and sun's gravity pulling in the same direction