Ch 13 - Homeostasis Flashcards
Homeostasis
Maintaining physiological traits w/in a specific range (set point or set range)
Motivation
A drive state that prompts homeostatic behaviors
Obligatory losses
Unavoidable loss of a regulated variable such as energy, water, or temp, as a consequence of life processes.
POA body temp regulation
Physiological responses (ex. Shivering)
Lateral hypothalamus (LH) body temp
Behavioral responses. Ex change exposure of skin.
Receptors that detect body temp
In skin, body core, hypothalamus.
Report to spinal cord, brainstem, and hypothalamus.
Intracellular compartment
The fluid space of the body that is contained within cells
Exrracellelar compartment
The fluid space of the body that exists outside the cells
Aquaporins
Channels spanning cell membranes that are specialized for conducting water molecules in or out of cell
Osmotic pressure
The tendency of a solvent to move through a membrane in order to equalize the concentration of solute.
Osmolality
Number of solute particles per unit volume of solvent
Hypovolemic thirst
Thirst based on reduced volume of extracellular fluid. Lose equal amounts of salt and water
Osmotic thirst
Thirst stimulated by loss of water from the extracellular compartment. More water lost than salt. Alters solute concentration between intra and extra cellular space
Atrial natriuretic peptide (ANP)
Released from heart that normally reduces bp, inhibits drinking and promotes excretion of water and salt at the kidneys. Decreases w hypovolemic thirst
Vasopressin aka ADH
Secreted by posterior pituitary. Tells kidney to conserve water, constricts blood vessels to raise bp
