Biology Questions

Receptors for hearing the organ of corti or the spiral organ is located in the the mammalian cochlea.

The oxygenated blood  flows through pulmonary veins then leaves the lungs, which return it to the left heart, completing the pulmonary cycle.

Arteries carry oxygenated blood away from the heart to the tissues, except for pulmonary arteries, which carry blood to the lungs for oxygenation (usually veins carry deoxygenated blood to the heart but the pulmonary veins carry oxygenated blood as well).

"Glycolysis" means the splitting of glucose. The first step of the process occurs in the cytoplasm of the cell and yields a small amount of energy (measured in units of ATP) and two molecules of pyruvate.

The other steps occur in the mitochondria. It is an ongoing process as your cells have a constant need for energy.

Urea is a by product of amino acid catabolism, Which occurs in the liver. The nitrogen in the  amino acid becomes converted to ammonia and this is further converted by the liver into urea