How do cells maintain homeostasis in different environmental conditions?

Homeostasis at the cellular level is critical to maintaining homeostasis in the whole organism. Animal cells have several ways to help them stay in equilibrium.

The cell membrane functions as a boundary separating the internal cellular environment from the external environment. It is selectively permeable which means it lets some materials pass through but regulates the passage of other materials.

There are several ion transport mechanisms within the cell membrane that function to maintain proper levels of solutes inside and outside the cell. One of the most important is the sodium-potassium ATPase pump.Another critical pump is the calcium ATPase pump which moves calcium out of the cell or pumps it into the endoplasmic reticulum. This transfer of ions back and forth across the membrane creates a membrane potential that drives the ionic currents.

There are three basic kinds of intercellular communication used to maintain homeostasis. The first is when direct contact occurs between the membranes of two cells and they signal to each other. The second is when cells use short range chemical signals over short distances. The third is long ranged signals that are secreted into the bloodstream and can be carried anywhere in the body.

cellular respiration oxidizes food into energy in the form of atps.

glycolysis (6 c hexose) > 2x atps are used > 6c hexose biphosphate > 2 x 3c triphosphate >

2 x 3c pyruvate (2x nadh produced from nad) and (4x atp produced)

pyruvate actively pumped mitochondrial matrix.