What organ, from the digestive system, produces an enzyme/molecule that digest fats?

A complete cardiac cycle of the heart consists of the heart filling with blood, diastole (relaxed period), and then pumping out the blood, systole (contraction phase).

How does negative feedback work?

What is the name of the body part at number 8?  

Kidneys absorb digested nutrients into the bloodstream were Villi and microvilli increase the surface area for nutrient absorption.

Which chamber of the heart receives the oxygenated blood returning from the lungs first?

What is the energy molecule of the cell?

When a neuron is at rest the voltage, that will need to be overcome to send the signal down the neuron is called?

  The structure at number 9 is?

Which term is used to define the exchange of gases between blood and air?