Although there are many different hormones in the human body, they can be divided into three classes based on their chemical structure. What are these classes and what is one factor that distinguishes them?
Although there are many different hormones in the human body, they can be divided into three classes based on their chemical structure: lipid-derived, amino acid-derived, and peptide hormones. One of the key distinguishing features of the lipid-derived hormones is that they can diffuse across plasma membranes whereas the amino acid-derived and peptide hormones cannot.
Where is insulin stored, and why would it be released?
Secreted peptides such as insulin are stored within vesicles in the cells that synthesize them. They are then released in response to stimuli such as high blood glucose levels in the case of insulin.
Glucagon is the peptide hormone that signals for the body to release glucose into the bloodstream. How does glucagon contribute to maintaining homeostasis throughout the body? What other hormones are involved in regulating the blood glucose cycle?
Glucagon acts in opposition to insulin, the peptide hormone that stimulates cells to take up glucose from the bloodstream, to maintain blood glucose within healthy levels. When glucagon is released into the blood in response to falling blood sugar levels, the liver catabolizes its glycogen stores to release glucose. If glucagon does not function properly, the blood sugar will drop too low from insulin signaling driving cellular uptake from the blood.