Homeostasis and Feeding Behavior Flashcards
Homeostasis
The active process of maintaining and particular physiological parameter relatively constant.
Set Point
The point of reference in a feedback system
Set Zone
Range of variable that a feedback system tries to maintain
Examples of a set zone
Temp, pH, [Na+], hormone levels, …
Homeostatic Control Mechanisms
Regulates Homeostasis
2 types of Homeostatic Control Mechanisms
Positive and Negative Feedback
Negative Feedback
V COMMON, Output of a system feeds back to reduce the effect of input signals
Pathway of Homeostatic Control Mechanisms
Stimulus, Receptor, Afferent Pathway, Integrating, Efferent Pathway, Effector, Response, Negative Feedback ->
Positive Feedback
V RARE, End products of an action causes more of the action to occur
Osmoregulation
Maintenance of constant balance of water and dissolved materials
Osmosis
Passive movement of water molecules from one place to another until uniform concentration is achieved
2 Triggers of Osmoregulation
Osmotic Thirst, Hypovolemic Thirst
Osmotic Thirst
Ingestion of Salty Foods, loss of water more than salt (sweat, urine).
Osmosensory Neurons of Hypothalamus
Osmoreceptors- Trigger Drinking
Hypovolemic Thirst
Decrease in overall volume of extracellular fluid (NOT A CHANGE IN CONCENTRATION)
Examples of hypovolemic thirst
Hemorrhage, Vomiting, Chronic Diarrhea
RAAS
Renin-Angiotensin-Aldosterone System
Feeding
Needed to build, maintain, and fuel our bodies
Nutrients
Chemicals required for effective functioning, growth, and maintenance of our body
Digestion
Process of breaking down ingested food
Digestion Facts
33% of food lost via digestion; 55% of food consumed by basal metabolism; 12% of food for active behavioral processes
Satiety Hormones
Insulin, Leptin
Hunger Hormones
Grehlin, Orexin
3 Sources of Energy
Protein, Carbohydrates, Fats
