AP BIOLOGY

Detailed explanation-1: -The cellular organelle/part present in all cells and helps maintain homeostasis are Endoplasmic reticulum (organelle) and plasma membrane (cellular part). They both effectively keep the homeostatic rate of the cell constant via osmosis and thus play a vital role in controlling cellular activities.

Detailed explanation-2: -Role of mitochondria in nutrient homeostasis The mitochondrion also earned the center stage. In addition to its traditional role as the cell’s power plant, this organelle engages in homeostatic processes such as nutrient sensing and lipid catabolism.

Detailed explanation-3: -Homeostasis is maintained by a series of control mechanisms functioning at the organ, tissue or cellular level. These control mechanisms include substrate supply, activation or inhibition of individual enzymes and receptors, synthesis and degradation of enzymes, and compartmentalization.

Detailed explanation-4: -By serving as the major intracellular calcium (Ca2+) storage compartment, the ER plays a critical role in maintaining Ca2+ homeostasis among various cellular organelles [5, 6].

Detailed explanation-5: -Final Answer: Homeostasis in the cell is maintained by a plasma membrane.