Chapter 12: Ingestive Behavior Flashcards by Fritzy Gletch Berdin

Four essential features of regulatory mechanism.

System variable
Set point
Detector
Correctional mechanism

How well did you know this?

Not at all

Perfectly

The characteristic to be regulated.

System variable

How well did you know this?

Not at all

Perfectly

The optimal value of the system variable.

Set point

How well did you know this?

Not at all

Perfectly

Monitors the value of the system variable.

Detector

How well did you know this?

Not at all

Perfectly

Restores the system variable to the set point.

Correctional mechanism

How well did you know this?

Not at all

Perfectly

A process whereby the effect produced by an action serves to diminish or terminate the action; regulates the activity of the system.

Negative feedback

How well did you know this?

Not at all

Perfectly

Brain-based mechanisms that reduce hunger or thirst related to behaviors that result in adequate intake of nutrients or water.

Satiety mechanisms

How well did you know this?

Not at all

Perfectly

The fluid portion of the cytoplasm of cells.

Intracellular fluid

How well did you know this?

Not at all

Perfectly

Includes the intravascular fluid, the cerebrospinal fluid, and the interstitial fluid.

Extracellular fluid

How well did you know this?

Not at all

Perfectly

The blood plasma.

Intravascular fluid

How well did you know this?

Not at all

Perfectly

Fluid that bathes our cells.

Interstitial fluid

How well did you know this?

Not at all

Perfectly

A condition where if the blood volume falls too low, the heart can no longer pump the blood effectively; if the volume is not restored, heart failure will result.

Hypovolemia

How well did you know this?

Not at all

Perfectly

Refers to the metering (measuring) of the volume of the blood plasma.

Volumetric

How well did you know this?

Not at all

Perfectly

Refers to an increase in osmotic pressure on intracellular fluid that occurs when a cell is dehydrated; refers to the fact that the detector cells are actually responding to (metering) changes in the concentration of the interstitial fluid that surrounds them.

Osmometric

How well did you know this?

Not at all

Perfectly

Refers to a sensation that people say they have when they are dehydrated; a tendency to seek water and to ingest it.

Thirst

How well did you know this?

Not at all

Perfectly

Occurs when the solute concentration of the interstitial fluid increases.

Osmometric thirst

How well did you know this?

Not at all

Perfectly

Substances, such as salts, dissolved in a solution.

Solute

How well did you know this?

Not at all

Perfectly

The movement of water through a semipermeable membrane from a region of low solute concentration to one of high solute concentration.

Osmosis

How well did you know this?

Not at all

Perfectly

Neurons whose firing rate is affected by their level of hydration.

Osmoreceptors

How well did you know this?

Not at all

Perfectly

A brain region where the osmoreceptors responsible for osmometric thirst are located.

Lamina terminalis

How well did you know this?

Not at all

Perfectly

Two specialized circumventricular organs contained in the lamina terminalis; found outside the blood-brain barrier.

Organum Vasculosum of the Lamina Terminalis (OVLT)
Subfornical Organ (SFO)

How well did you know this?

Not at all

Perfectly

Occurs when the volume of the blood plasma—the intravascular volume—decreases.

Volumetric thirst

How well did you know this?

Not at all

Perfectly

A hormone that initiates drinking and a salt appetite, causes the kidneys to conserve water and salt, and increases blood pressure.

Angiotensin

How well did you know this?

Not at all

Perfectly

A small nucleus wrapped around the front of the anterior commissure; part of the lamina terminalis; receives and integrates osmometric and volumetric information.

Median preoptic nucleus

How well did you know this?

Not at all

Perfectly

A fiber bundle that connects the amygdala and anterior temporal lobe.

Anterior commissure

Refers to lack of drinking caused by the damage in the lamina terminalis region.

Adipsia

Takes place while the digestive tract is empty.

Fasting phase

Takes place while the digestive tract is full; occurs when food is present in the digestive tract.

Absorptive phase

A complex, insoluble carbohydrate.

Glycogen

A peptide hormone produced by the pancreas.

Insulin

A peptide hormone that stimulates the conversion of glycogen into glucose.

Glucagon

Are complex molecules that contain glycerol (also called glycerine) combined with three fatty acids (stearic acid, oleic acid, and palmitic acid).

Triglycerides

Protein molecules that are situated in the membrane and are similar to those responsible for the reuptake of transmitter substances.

Glucose transporters

A peptide hormone that is released from the gastrointestinal system when individuals are in the fasting phase and the digestive system is empty.

Ghrelin

A fall in blood glucose level.

Hypoglycemia

Deprive cells of glucose.

Glucoprivation

Depriving cells of lipids.

Lipoprivation

Connects the liver with the brain.

Vagus nerve

Include information about the appearance, odor, taste, texture, and temperature of food.

Sensory factors

A peptide hormone which causes the gallbladder (cholecyst) to contract, injecting bile into the duodenum.

Cholecystokinin (CCK)

A drug extracted from chile peppers that destroys sensory axons in the vagus nerve.

Capsaicin

Is released by the small intestine after a meal in amounts proportional to the calories that were just ingested.

Peptide YY 3–36 (PYY)

A peptide hormone that is normally secreted by well nourished fat cells.

Leptin

Disconnects the motor neurons of the brain stem and spinal cord from the neural circuits of the cerebral hemispheres that normally control them.

Decerebration

Peptides that stimulate hunger and decrease metabolic rate, thus increasing and preserving the body’s energy stores.

Melanin-concentrating Hormone (MCH) Orexin

Appetite-inducing chemicals.

Orexigens

A system of neurons that secrete a neurotransmitter which is an extremely potent stimulator of food intake.

Neuropeptide Y (NPY)

Where the cell bodies of most of the neurons that secrete NPY are found; located in the hypothalamus at the base of the third ventricle.

Arcuate nucleus

A region of the hypothalamus where infusions of NPY affect metabolic functions, including the secretion of insulin.

Paraventricular nucleus (PVN)

A potent and extremely long-lasting orexigen.

Agouti-related protein (AGRP)

A peptide anorexigen that appears to play an important role in satiety; injection into the cerebral ventricles inhibits feeding, including the feeding stimulated by NPY.

Cocaine- and Amphetamine-regulated Transcript (CART)

An anorexigen that is released by CART neurons; an agonist of the melanocortin 4 receptor (MC4R); binds with the receptor and inhibits feeding.

α-melanocyte-stimulating hormone (α-MSH)

Caused by genetic differences—and their effects on development of the endocrine system and brain mechanisms that control food intake and metabolism.

Obesity

People with an efficient metabolism have calories left over to deposit in the long-term nutrient reservoir, and these calories accumulate in the form of increased adipose tissue.

Thrifty phenotype

People with an inefficient metabolism that can eat large meals without getting fat.

Spendthrift phenotype

Designed to reduce the amount of food that can be eaten during a meal or interfere with absorption of calories from the intestines.

Bariatric surgery

This procedure produces a small pouch in the upper end of the stomach; the effect is to produce a small stomach whose contents enter the jejunum, bypassing the duodenum.

Roux-en-Y gastric bypass (RYGB)

A drug that interferes with the absorption of fats by the small intestine.

Orlistat

Type of therapies for obesity.

Surgery Drug treatment Exercise

A disorder where people eat too little, even to the point of starvation.

Anorexia nervosa

A disorder that is characterized by a loss of control of food intake.

Bulimia nervosa

A disorder that is characterized by eating a large quantity of food in a relatively short period of time and a loss of control over eating behavior.

Binge-eating disorder

Is caused by blood loss, vomiting, and diarrhea.

Pure volumetric thirst

Sustains our fuel needs for several hours between meals; supplies nutrients to the brain during brief periods of fasting (between meals).

Short-term reservoir

Consists of adipose tissue; filled with fats or, more precisely, with triglycerides; supplies nutrients to the brain and body during prolonged periods of fasting.

Long-term reservoir

Apparently contains receptors that can detect the presence of nutrients.

Stomach

Are activated by the entry of food into the stomach.

Gastric satiety factors

Are activated by the passage of food from the stomach into the duodenum.

Intestinal satiety factors

Possess nutrient detectors that convey satiety signals.

Intestines

Contains neural circuits that are able to control acceptance or rejection of sweet or bitter foods and can even be modulated by satiation or physiological hunger signals, such as a decrease in glucose metabolism or the presence of food in the digestive system.

Brain stem

A special form of gastric bypass operation, is one successful form of bariatric surgery; its effectiveness is probably due primarily to its suppression of ghrelin secretion and stimulation of PYY secretion.

The RYGB procedure