Chapter 12 - Hunger, Eating, and Health Flashcards
Set point
The value of a physiological parameter that is maintained constantly by physiological or behavioral mechanisms; for example, the body’s energy resources are often assumed to be maintained at a constant optimal level by compensatory changes in hunger
Digestion
The process by which food is broken down and absorbed through the lining of the gastrointestinal tract
Gut microbiome
The bacteria and other organisms that live inside our gastrointestinal tract
Lipids
Fats
Amino acids
The building blocks of proteins
Glucose
A simple sugar that is the breakdown product of complex carbohydrates; it is the body’s primary, directly utilizable source of
energy
Cephalic phase
The metabolic phase during which the body prepares for food that is about to be absorbed
Absorptive phase
The metabolic phase during which the body is operating on the energy from a recently consumed meal and is storing the excess as body fat, glycogen, and proteins
Fasting phase
The metabolic phase that begins when energy from the preceding meal is no longer sufficient to meet the immediate needs of the body and during which energy is extracted from fat and glycogen stores
Insulin
A pancreatic hormone that facilitates the entry of glucose into cells and the conversion of bloodborne fuels to forms that can be stored
Glucagon
A pancreatic hormone that promotes the release of free fatty acids from adipose tissue, their conversion to ketones, and the use of both as sources of energy
Gluconeogenesis
The process by which protein is converted to glucose
Free fatty acids
The main source of the body’s energy during the fasting phase; released from adipose tissue in response to high levels of glucagon
Ketones
Breakdown products of free fatty acids that are used by muscles as a source of energy during the fasting phase
Set-point assumption
The assumption that hunger is typically triggered by a decline in the body’s energy reserves below their set point
Negative feedback systems
Systems in which feedback from changes in one direction elicit compensatory effects in the opposite direction
Homeostasis
A stable internal environment
Glucostatic theory
The theory that eating is controlled by deviations from a hypothetical blood glucose set point
Lipostatic theory
The theory that eating is controlled by deviations from a hypothetical body-fat set point
Positive-incentive theory
Theories holding that the primary factor in most cases of addiction is the craving for the positive-incentive (expected pleasure-producing) properties of the drug
Positive-incentive value
The anticipated pleasure associated with a particular action, such as taking a drug
Satiety
The motivational state that terminates a meal when there is food remaining
Nutritive density
Calories per unit volume of a food
Sham eating
The experimental protocol in which an animal chews and swallows food, after which the food immediately exits its body through a tube implanted in its esophagus
Appetizer effect
The increase in hunger that is produced by the consumption of small amounts of food
Cafeteria diet
A diet offered to experimental animals that is composed of a wide variety of palatable food
Sensory-specific satiety
The fact that the consumption of a particular food produces greater satiety for foods of the same taste than for other food
Ventromedial hypothalamus (VMH)
The area of the hypothalamus that was once thought to be a satiety center
Lateral hypothalamus
The area of the hypothalamus once thought to be the feeding center
Hyperphagia
Excessive eating
Dynamic phase
The first phase of the VMH syndrome, characterized by grossly excessive eating and rapid weight gain
Static phase
The second phase of the VMH syndrome, during which the obese animal maintains a stable level of obesity
Aphagia
Complete cessation of eating
Adipsia
Complete cessation of drinking
Lipogenesis
The production of body fat
Lipolysis
The breakdown of body fat
Paraventricular nuclei
Hypothalamic nuclei that play a role in eating and synthesizing hormones released by the posterior pituitary
Arcuate nucleus
A nucleus of the hypothalamus that contains high concentrations of both leptin receptors and insulin receptors
Duodenum
The upper portion of the intestine through which most of the glucose and amino acids are absorbed into the bloodstream
Cholecystokinin (CKK)
A peptide that is released by the gastrointestinal tract and is thought to function as a satiety signal
Prader-Willi syndrome
A neurodevelopmental disorder that is characterized by insatiable appetite and exceptionally slow metabolism
Diet-induced thermogenesis
The homeostasis-defending increases in body temperature that are associated with increases in body fat
Basal metabolic rate
The rate at which energy is utilized to maintain bodily processes when resting
Settling point
The point at which various factors that influence the level of some regulated function (such as body weight) achieve an equilibrium
Leaky-barrel model
An analogy for the settling-point model of body-gat regulation
Nonexercise activity thermogenesis (NEAT)
Nonexercise activity thermogenesis, which is generated by activities such as fidgeting and the maintenance of posture and muscle tone
Gut microbiome
The bacteria and other organisms that live inside our gastrointestinal tract
Leptin
A protein normally synthesized in fat cells; it is thought to act as a negative feedback signal normally released by fat stores to decrease appetite and increase fat metabolism
Ob/ob mice
Mice that are homozygous for the mutant ob gene; their body fat produces no leptin, and they become very obese
Subcutaneous fat
Fat stored under the skin
Visceral fat
Fat stored around the internal organs of the body cavity
Neuropeptide Y
A gut hunger peptide
Melanocortins
A class of peptides that includes the gut satiety peptide α-melanocyte-stimulating hormone
Melanocortin system
Neurons in the arcuate nucleus that release melanocortins
Gastric bypass
A surgical procedure for treating obesity in which the intestine is cut and connected to the upper portion of the stomach, which is isolated from the rest of the stomach by a row of staples
Adjustable gastric band procedure
A surgical procedure for treating obesity in which an adjustable band is implanted around the stomach to reduce the flow of food
Anorexia nervosa
An eating disorder of underconsumption that results in health-threatening weight loss
Bulimia nervosa
An eating disorder characterized by periods of not eating interrupted by bingeing followed by purging
