PSY 3460 Ch. 9
motivation
changes in internal environment can affect this; the psychological process the induces or sustains a certain behavior
set point
desired value our bodies are trying to maintain; when it is deviated from, compensatory action may begin
Basal metabolism
energy used for heat production, maintenance of membrane potentials, and life-sustaining processes
lipid
fat molecules that can be stored for long-term energy
Orexin
from the lateral hypothalamus participates in control of feeding behavior
glycogen
glucose stored in the liver and muscles for a short-term; regulated by the pancreatic hormone insulin
leptin
hormone that signals the hypothalamus and brain stem to reduce appetite and increase the amount of energy used; provides information to the brain about long-term energy reserves
aldosteron
hormone that stimulate the body to retain sodium (NA+)
Vasopressin
hormone that stimulate the body to retain water
osmosensory neurons
in the hypothalamus and in the OVLT; monitor the concentration of extracellular fluid.
GLP-1
increased during meals; suppresses appetite; blocks effects of ghrelin
Bulimia
individuals believe themselves to be fatter than they are; periodically gorge themselves and then either vomit or take laxatives to avoid weight gain
anorexia nervosa
is a syndrome in which individuals deprive themselves of food; they are often obsessed with food
arcuate nucleus
key in integrating peptide hormone signals from the body
hypovolemic thirst
low extracellular volume from a loss of bodily fluids; the concentration of the fluid has not changed - salt and ions are also lost
diffusion
molecules of a substance (solute) dissolved in another substance (solvent) will move until a uniform concentration is achieved.
Hormones
molecules released by a cell into the bloodstream, where they can travel to the body's target tissues and bind to their receptors in the tissue, causing some sort of effect
ossmosis
passive movement of water through a semipermeable membrane between solutions of different solute concentrations until both sides are equal.
binge eating
people gorge themselves with excess food, to the point of illness
glucose
principle sugar used for energy
PYY3-36
released by intestinal cells; reaches high levels after eating and works as an appetite suppressant
diabetes mellitus
results from failure of insulin to induce glucose absorption; type I: the pancreas stops producing insulin; type II: great reduction in tissue sensitivity to insulin
extracellular compartment
the fluid in the space outside of cells, divided between interstitial fluid and blood plasma
Intracellular compartment
the fluid part of the body contained within cells
osmotic pressure
the force that pushes or pulls water across the membrane
Homeostasis
the maintenance of a stable, balanced internal environment
ventromedial hypothalamus (VMH)
the part of the hypothalamus that can cause one to stop eating; believed to be the satiety center
osmotic thirst
thirst for water may be triggered by high extracellular solute concentration, or very salty fluids
ghrelin
A hunger-arousing hormone secreted by an empty stomach; high-levels before they eat.
negative feedback
A primary mechanism of homeostasis, when homeostasis is achieved, the behavior will stop until we fall out of homeostasis again
ectotherms
An animals that warms itself mainly by absorbing heat from its surroundings
a
An excess of glucose in urine is symptomatic of a. diabetes mellitus. b. the ingestion of too much salt. c. the ingestion of too much sugar. d. dehydration.
endotherms
Animals (such as birds or mammals) that can regulate their body temperature.
c
Research on the effects of leptin indicates that activation of POMC neurons in the hypothalamus a. induces hunger. b. promotes orexin release. c. suppresses hunger. d. promotes leptin biosynthesis.
a
The hormone _______ is generated in the kidney via a cascade of enzymatic actions in response to hypovolemia. a. angiotensin II b. ANP c. vasopressin d. insulin
lateral hypothalamus
The part of the hypothalamus that produces hunger signals
c
The population of beneficial bacteria, fungi, and viruses that inhabit the large intestine of human beings is referred to as a a. microtype. b. fecal transplant. c. microbiome. d. biome regulator.
c
The receptors that detect drops in extracellular volume are located in the a. kidneys. b. hypothalamus. c. vascular system. d. ventricular system.
c
The response to an increase in the salt concentration of the extracellular solution is called _______ thirst. a. hypovolemic b. osmoreceptive c. osmotic d. hypotonic
a
Which example demonstrates ectothermic behavior? a. A turtle basking on a sunny log b. A person shivering in a cold house c. A dog panting on a hot day d. A group of birds roosting together at night
c
Which pancreatic hormone promotes the conversion of glycogen to glucose? a. Aldosterone b. Insulin c. Glucagon d. CCK
d
Which response is not a physiological response of the mammalian thermoregulatory system? a. Sweating b. Constriction of cutaneous blood vessels c. Increased thyroid activity d. Lying in the shade
c
Which statement about anorexia nervosa is true? a. It affects both young men and women equally. b. It is characterized by bouts of binging and purging. c. People with anorexia think about food a great deal. d. The word "anorexia" is derived from a Greek word meaning "great hunger."
glucagon
a hormone that converts glycogen to glucose when glucose levels drop
Cholecystokinin (CCK)
a peptide released by the gut after feeding and acts on the vagus nerve to inhibit appetite
Endocannabinoids
act directly on the hypothalamic appetite regulation
gut microbiota
all of the microorganisms that live in the gut
circumventricular organ
any of multiple distinct sites that lie in the wall of a cerebral ventricle and monitor the composition of the cerebrospinal fluid; contains the OVLT
Baroreceptors
blood vessels in the heart that detect a drop in pressure