classnotes9 - Hormones definition a chemical signal...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Hormones: definition - a chemical signal released into body fluids. Generally this regulates or causes a specific action. Usually, only specific cells known as target cells will respond, but some hormones can affect many different systems: A simple example: Adrenal gland -> epinephrine -> raises blood sugar level, increases heart rate, generally increases metabolic activity. [target cells include liver, heart, lungs.] Endocrine glands - glands that secrete hormones. The human body has lots, only some of which will be covered here [Fig. 26.3, p. 520] . (Also, exocrine glands -> essentially hormones that are released outside body e.g., pheromones). See table on p. 521 for a list of hormones in humans (not exhaustive). Hypothalamus/pituitary: Pituitary - a small gland at base of brain. Composed of two parts : Anterior pituitary - directly controlled by the hypothalamus (through a portal vein system). - synthesizes and secretes hormones depending on whether or not a “releasing hormone” or “inhibiting hormone” is produced by the hypothalamus. All hormones made here have at least a “releasing hormone”. - hormones produced here include:
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 07/21/2011 for the course BIO 101 taught by Professor Staff during the Spring '08 term at Northern Virginia Community College.

Page1 / 3

classnotes9 - Hormones definition a chemical signal...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online