Endocrine System Flashcards
What is the endocrine system? What do the glands do?
Endocrine glands secrete hormones into the bloodstream
What are hormones
Chemical messages release in one part of the body, travel through bloodstream and affect the activities of target cells in other parts of the body
Example of nervous x endocrine system
Endocrine system is much slower than the nervous system, but they work together
Nervous system: reaction to a hot stove
Endocrine: growth rate as a teenager
Endocrine hormones
We have over 200 hormones or hormone like chemicals within the body
They can
Regulate growth and development
Change metabolism
Blood sugar
Blood pressure
Immune response
Gigantism
When too much growth hormones (GH) are released in early childhood
Pituitary dwarfism
Too few growth hormones produced
Regulation of hormones
The hypothalamus receives signals from various sensors in the body and releases “releasing hormones” these stimulates the pituitary gland
Tropic hormones
Hormones that stimulate endocrine glands to release other hormones are called tropic hormones. Most released from hypothalamus and pituitary glands are tropic hormones
2 types of hormones
Steroid hormones: fat soluble molecules made from cholesterol : cortisol
Protein hormones: water soluble, molecules derived from amino acids or chains of amino acids
Steroid hormones
Lipids and hydrophobic, meaning they can easily interact with cell membranes that consist of phospholipids
Therefore when a steroid hormone travels through the blood and encounters a cell, it does not stop at an cell membrane to get in. It simply can shoot through!
Protein hormones
A hydrophilic hormone cannot get into a cell, it can only bind to a receptor located on the outside of its target cells membrane
But the hormone is brining a message from your body to that target cell
Because the hormone tells the target cell that it needs to carry our some function for the body it is refereed to as the first messenger
Second messenger?
Within a target cell and must continue to carry the message of the hormone within the cell to get the job done
—> known as cAMP