Lecture 3: Homeostasis Flashcards
Homeostasis is the envelope of ____ conditions which allows us to live. What’s the difference between external and internal perturbations?
Internal. External perturbations would be things like environmental temp. change, internal would be sugar in food.
The _____ nervous system is dedicated to maintaining homeostasis. Animals, humans included, maintain _____ balance.
Autonomic, dynamic.
The two ways the regulate homeostasis are ______ and _______ feedback loops. The _______ is the ‘thing’ to regulate. The movement of the system away from its ___ _______ is the ________.
Positive, negative, variable, set point, stimulus.
A ________ or _________ to detect change in variable. A _____ ________ to figure out what to do when stimulus is detected. An _______ to move the variable back to set point.
Detector, receptor, control center, effector.
Large deviations from the ___ ______ make it impossible to maintain _________.
Set point, homeostasis
The body is run by __________ signaling. The voltage of the cell cytoplasm is between ____ and _____ mV.
Electrochemical, -40, -70
Potential ____ occurs when there is a separation of ___________ charge. There is _______ energy due to the __________ in distribution of electrical charges.
Difference, electrical, potential, difference
There are more _____ ions on the _______ of the plasma membrane so there is a small charge separation. Why do sodium ions want to enter the cell?
Negative, inside. Sodium wants to go down its concentration gradient, go down the charge gradient.
Why do potassium ions want to leave the cell?
Potassium wants to go down the concentration gradient. When it leaves the cell, the potential difference becomes greater.
What maintains RMP homeostasis?
The membrane is much less permeable to sodium ions than potassium ions. There is always a slight negative charge inside.
___________ feedback mechanisms bring homeostasis further from the set point. Name 3 examples of these feedback loops.
Positive. Ex. orgasm, ovulation, blood clotting, uterine contractions, etc.
Any prolonged __________ from homeostasis results in some sort of ______ or ________.
Departure, disorder, disease
