Local and Long Distance Communication
Endocrine:
Paracrine:
Feedback Pathway:
All hormones are secreted from a specific gland and released to act upon the target cells.
Endocrine:
- Long distance communication between cells
- Regulators (signal) is released in the bloodstream
- Ex. Epinephrine is released into the bloodstream in response to a fight or flight situation
Paracrine:
- Local communication between cells
- Cell-cell recognition
- Regulator (signal) diffuses through extracellular fluid
- Ex. Blood clotting usually only occurs where there is an injury
Feedback Pathway:
All hormones are secreted from a specific gland and released to act upon the target cells.
Insulin
Insulin is a hormone produced by the pancreas. It's role in the body is to help cells absorb glucose. After a meal, glucose levels in the bloodstream become higher as carbohydrates and other sugars from the foods are absorbed. When this happens, it triggers the pancreas to release insulin into the bloodstream. The presence of insulin in the blood alerts the cells to the presence of glucose which the cells then absorb. This keeps the sugar level in the blood constant.