What is an analogy for active transport and passive transport?

Explanation:

Active transport occurs when a solute must pass through the cell membrane against its concentration gradient. A good analogy is that this is like pushing the water that fell over a waterfall, back up the river to the falls above.

answer: all : )

explanation:

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.