Lecture 1-Homeostasis And Cell Function Flashcards
Why is homeostasis important to physiological processes?
All life has certain parameters (Temp, BP, BGL, etc.) that must be maintained for continued survival physiologic processes work to keep these in check.
Define homeostasis
The “stable internal environment” of an organism.
A change to hemostasis produces an effect that reduces the change.
Negative feedback
A change in homeostasis occurs, and the effector increases the degree of change.
Positive feedback
Something that creates a change to the internal environment.
Stress
Most abundant extracellular cation
Na
Most abundant intracellular ion
K
Most abundant extracellular anion
Chloride
F(x)s of the plasma membrane:
- selectivity filter
- endo/exocytosis
- receptors tell about environment
Intracellular trafficking organelles
Golgi
E.R.
Organelle associated with ATP production
Mitochondria
Transport compounds to the lysosome
Endo some
Digests phagocytized material
Lysosome
Describe the process of endocytosis.
- molecule to be phagocytized binds to extracellular receptor
- clathrin coated pit forms
Invaginate so to become endosome - fuses w/1* lysosome to form 2* lysosome
- digestion
- exocytosis
What is contained in lysosome?
Acidic hydrolases at low pH (p+ pump)
