14. Thirst Flashcards
What do drive reduction theories place emphasis on? (Thirst psychobiology)
Homeostasis
What is the equation for motivation? (Thirst psychobiology)
motivation = homeostasis + negative feedback
What is negative feedback? (Thirst psychobiology)
The effect produced by an action that serves to diminish or terminate that action
What is a system variable? (Thirst psychobiology)
Variable controlled by the system
What is the set-point? (Thirst psychobiology)
Desired level of the variable
What is sensory? (Thirst psychobiology)
Mechanism for measuring the variable
What is the effector system? (Thirst psychobiology)
behavioural/physiological mechanisms to change variables and restore homeostasis
How do humans generate heat? (Thirst psychobiology)
Via metabolism
How much of our lean body mass is made up of water? (Thirst psychobiology)
70%
What is osmometric thirst? (Thirst psychobiology)
Cellular dehydration
What does it lead to when water is lost and salt concentration increases? (Thirst psychobiology)
Osmotic imbalance between extracellular and intracellular compartments
What is organum vasuulosum of the lamina terminalis? (Thirst psychobiology)
Holds the osmotic receptors to sense changes
What is hypovolemic thirst? (Thirst psychobiology)
Sensed through pressure, dealing with volume of fluid, not to do with water loss
What does hypovolemia cause? (Thirst psychobiology)
The release of renin enzyme from the kidneys
What does the renin enzyme do? (Thirst psychobiology)
Converts angiotensinogen into angiotensin
