BIOMOLECULES AND ENZYMES

Detailed explanation-1: -In endocrine signaling, the signaling molecules (hormones) are secreted by specialized endocrine cells and carried through the circulation to act on target cells at distant body sites.

Detailed explanation-2: -Multiple hormones such as ghrelin, leptin, cholecystokinin, and other peptides all relay peripheral signals to the hypothalamus.

Detailed explanation-3: -There are four categories of chemical signaling found in multicellular organisms: paracrine signaling, endocrine signaling, autocrine signaling, and direct signaling across gap junctions (Figure 9.2).

Detailed explanation-4: -The endocrine system uses chemical signals called hormones to convey information from one part of the body to a distant part of the body. Hormones are released from the endocrine cell into the extracellular environment, but then travel in the bloodstream to target tissues.

Detailed explanation-5: -Insulin signaling is an example of endocrine signaling. Insulin signaling is an important form of cell signaling for the maintenance of homeostatic blood sugar levels. The ductless gland that produces insulin is known as the Islets of Langerhans. It is part of the pancreas.