Chapter 6 Flashcards
motivation
refers to the factors that initiate, sustain, and direct behaviors
instinct
-complex behavior that is automatic and unlearned
-been replaced by learned behaviors
incentive
-people are motivated by external stimulus
-can meet biological or nonbiological need
arousal
people behave to satisfy a certain level of their preferred sensation
drive
the body maintains homeostasis in it system
Homeostatic Drives
-motivate behavior
-state of the brain not conditions of the tissue
Temperature regulation
-control system maintains certain bodily conditions around a set point
-located in preoptic area of hypothalamus
ectotherms
cannot regulate body temperature internally
endotherms
maintain a constant internal temperature
Thirst
-our body is about 70% water
-maintaining our water is critical for life
— keeps our blood flowing
— maintains our body cells
— aids digestion
osmotic thirst
-when fluid in cells drop
-usually from eating a salty meal
-initiates drinking behavior
osmotic thirst pathway
OVLT -> median preoptic nucleus
Hypovolemic thirst
-when blood volume drops
-detected by baroreceptors and kidneys
hypovolemic thirst pathway
vagus nerve -> nucleus of the solitary tracts (NST) in medulla -> preoptic area
hunger
feeding behavior to provide energy for fuel and for maintaining body temp, growth, and repair cells
hunger pathway
taste buds -> NST -> insula (primary gustatory cortex)
Preoptic area regulates…
temperature and drinking behavior
Sensory-specific satiety
-food is less appealing the more you eat
-encourages variation in choices
-takes place in NST
learned taste acersion
avoiding food associated with illness or poor nutrition
learned taste preference
preference for the flavor of a food that contains a needed nutrition
Steps of Digestion
- Mouth - saliva breaks down starches into glucose
- Stomach - hydrochloric acid and pepsin mix with food to digest proteins into amino acid
- Small Intestine - duodenum is where the rest of digestion takes place
-fats transformed into fatty acids and glycerol by bile
-hepatic portal vein transports products to liver
Absorptive fase
glucose -> parasympathetic activation -> pancreas secretes insulin
-glucose enters body cells
-glucose stored in liver and muscles as glycogen
-fat is stored in adipose cells as triglycerides
Fasting phase
glucose decreases -> sympathetic activation -> pancreas secretes glucagon
-glycogen transformed to glucose
-stored fat is released as fatty acids and glycerol
Glucoprovic
low on glucose
lipoprovic hunger
low on fatty acids
ghrelin hunger
hormone released into blood stream at stomach empties during fasting
