Endocrine Part 1 Intro Miliotis Flashcards
What is homeostasis?
The process of maintaining a constant internal environment, despite external changing conditions
What is the meaning behind dynamic steady state?
Homeostasis is not equilibrium, but a stable state with oscillations around the setting point
What is negative feedback?
Mechanism that stabilizes the system by reversing the direction of the change
What is an example of negative feedback in involving cortisol regulation?
High levels of cortisol inhibit CRH and ACTH
What is positive feedback?
A mechanism that reinforces a change, moving a system further away from its setpoint
What is an example of positive feedback involving oxytocin?
Oxytocin during childbirth, when contraction leads to more oxytocin release
What are the different types of short distance communication?
Gap junctions, contact dependent, autocrine
What is the process of gap junctions?
Ions and molecules move between cells
Describe the process of contact dependent.
Membrane proteins bind to each other
Describe the process of autocrine .
Cells release signals affecting themselves
What is the type of long distance communication?
Neuroendocrine
How does the neuroendocrine system work?
Nervous system signals release into bloodstream
What do conflict reflexes involve?
Involve both systems and multiple integrating centres
What are simple reflexes mediated by?
Meditated by either neurons or endocrine system
What are the features of hormones? (3)
Can act on multiple tissues, alter target cell activity, must be regulated
What are hormones?
Chemicals produced by endocrine glands or other tissues and transported by the blood to target cells
Where are exocrine hormones released?
Into ducts like sweat glands
Where are the endocrine hormones released?
Into the bloodstream
What are the three methods of how hormones are identified?
Gland removal, gland replacement, extracts
What is the purpose of gland removal?
Observe effects of missing gland
What was the process of gland replacement?
Add missing gland back
What is the process of gland extract?
Test gland extracts in biological assays
