Endocrine glands release hormones into the bloodstream. This lets the hormones travel to cells in other parts of the body. The endocrine hormones help control mood, growth and development, the way our organs work, metabolism , and reproduction. The endocrine system regulates how much of each hormone is released.

The chemicals secreted by endocrine glands are called hormones, not enzymes.

Explanation:
- The endocrine glands are a group of ductless glands that secrete hormones directly into the bloodstream.
- Hormones are chemical messengers that are responsible for regulating various bodily functions and maintaining homeostasis.
- Unlike enzymes, which are proteins that act as catalysts for biochemical reactions, hormones are not directly involved in chemical reactions.
- Enzymes facilitate specific chemical reactions by lowering the activation energy required for the reaction to occur.
- On the other hand, hormones act as signaling molecules that bind to specific receptors on target cells and trigger a response.
- Enzymes are typically produced by various cells throughout the body, while hormones are primarily produced by specialized endocrine glands.
- Some examples of endocrine glands include the pituitary gland, thyroid gland, adrenal glands, pancreas, and ovaries/testes.
- Each endocrine gland secretes specific hormones that regulate different physiological processes in the body.
- For example, the pituitary gland secretes growth hormone, which regulates growth and development, while the thyroid gland secretes thyroxine, which controls metabolism.
- It is important to note that hormones are highly specific in their actions and usually act on target cells that have specific receptors for the hormone.
- Once a hormone binds to its receptor, it triggers a series of cellular responses that ultimately regulate the target cell's activity.
- Enzymes, on the other hand, are not specific to certain cells or tissues and can catalyze reactions throughout the body.
- In summary, while both hormones and enzymes are involved in regulating bodily functions, they have distinct functions and mechanisms of action. Hormones are the chemicals secreted by endocrine glands, not enzymes.