Functional Organization of the Endocrine System

These flashcards cover key terms and concepts associated with the functional organization of the endocrine system, including hormone classification, signaling mechanisms, and hormone interactions.

Levels of Organization

A hierarchy of biological structures, starting from atoms and increasing to organisms.

Endocrine System

A control system composed of glands that secrete hormones into the circulatory system.

Hormones

Chemical messengers secreted by endocrine glands that regulate body functions.

Half-life

The time it takes for half of a substance to be eliminated from the circulatory system.

Chronic Secretion

A hormone secretion pattern where a relatively constant concentration of hormone is maintained.

Acute Secretion

Rapid increase in hormone levels in response to a specific stimulus.

Episodic Secretion

A hormone release pattern that occurs at regular intervals.

Negative Feedback

Regulation mechanism where the output of a process inhibits its own production.

Receptor

Specific site where hormones bind to initiate a response in target cells.

Agonist

A drug that mimics the action of natural hormones.

Antagonist

A substance that blocks the action of a natural hormone.

G Protein-Coupled Receptors

A class of membrane receptors that activate intracellular signaling pathways.

Second Messengers

Intracellular mediators that transmit signals initiated by hormones.

Ligand-gated Ion Channels

Membrane proteins that open or close in response to hormone binding.

Signal Amplification

The process by which a single hormone activates multiple second messengers.

Synergistic Interaction

When two or more hormones work together to produce a greater effect.

Antagonistic Interaction

Hormones that counteract each other's effects in regulating physiological processes.

Nuclear Receptors

Receptors for lipid-soluble hormones that act on DNA to regulate gene expression.

Membrane-bound Receptors

Receptors for water-soluble hormones that trigger a rapid cellular response.

Cyclic AMP (cAMP)

A common second messenger that mediates the effects of many hormones.