Homestasis

Homeostasis

Stable internal environment maintained by physiological systems.

Set Point

Optimal range for physiological system function.

Set Zone

Range within which homeostasis operates effectively.

Negative Feedback

Counteraction of deviation to restore set point.

Thermoregulation

Process maintaining ideal body temperature.

Metabolism

Chemical processes generating heat in the body.

Behavioral Thermoregulation

Actions taken to prevent heat loss.

Hypothalamus

Brain region regulating homeostatic functions.

Preoptic Area (POA)

Hypothalamic area managing physiological temperature responses.

Shivering

Heat generated through muscle activity for warmth.

Vasoconstriction

Reduced blood flow to conserve body heat.

Lateral Hypothalamus

Region controlling behavioral temperature regulation.

Osmotic Thirst

Triggered by increased salt concentration in fluids.

Hypovolemic Thirst

Triggered by decreased blood volume or fluids.

Circumventricular Organs

Brain regions detecting fluid concentration changes.

Osmosensory Neurons

Neurons sensing salt concentration in cerebrospinal fluid.

Osmosis

Diffusion of solvent across a permeable membrane.

Fluid Loss

Reduction of body water due to normal processes.

Salt Retention

Kidneys conserve salts during dehydration.

Heat Exposure

Increased body surface area for warmth.

Reptilian Thermoregulation

Behavioral reliance on external heat sources.

Motivational Response

Behavioral drive to restore fluid balance.

Osmosis

Diffusion of solvent across a semipermeable membrane.

Hypovolemic thirst

Thirst triggered by low blood volume detection.

Osmotic thirst

Thirst due to high salt concentration outside cells.

POA

Region activating thirst responses in the brain.

Vasopressin

Hormone that promotes water retention by kidneys.

Baroreceptors

Sensors detecting blood vessel stretch or contraction.

Generator potential

Change in neuron potential due to cell shrinking.

Action potential

Electrical signal fired by neurons in response to stimuli.

Essential nutrients

Nutrients that must be obtained from diet.

Glucose

Primary sugar used for energy in the body.

Insulin

Hormone allowing glucose entry into cells.

Glycogen

Stored form of glucose in muscles and liver.

Glucagon

Hormone converting glycogen back to glucose.

Adipose tissue

Long-term storage site for excess glucose.

Metabolic adaptation

Decrease in metabolism with reduced energy intake.

Basal metabolism

Energy expenditure at rest for vital functions.

Trytophan

Amino acid precursor for serotonin neurotransmitter.

Omega-3

Essential fatty acids important for health.

Diabetes

Disease from insulin failure to regulate glucose.

Type-I diabetes

Juvenile-onset diabetes from insulin production failure.

Type-II diabetes

Adult-onset diabetes from cellular insulin resistance.

Basal Metabolism

Rate of energy expenditure at rest.

Metabolic Adaptation

Physiological adjustment to changes in energy intake.

Setpoint Theory

Body weight regulation point influenced by metabolism.

Hunger

Motivational drive to eat food.

Satiety

Feeling of fullness; absence of hunger.

Hypothalamus

Brain region regulating hunger and satiety.

POMC Neurons

Neurons that signal satiety and inhibit hunger.

NPY Neurons

Neurons that signal hunger and promote feeding.

Ghrelin

Hormone that stimulates hunger when food is absent.

Insulin

Hormone that reduces hunger after food intake.

Leptin

Hormone indicating long-term energy reserves from fat.

GLP-1

Hormone that stimulates insulin release and satiety.

Semaglutide

GLP-1 receptor agonist used for diabetes and weight loss.

Hedonic Eating

Eating driven by pleasure rather than hunger.

Energy Intake Regulation

Control of food consumption based on energy needs.

The Biggest Loser Study

Illustrates long-term weight regain post-weight loss.

Physiological Bias

Tendency to gain weight over losing it.

Arcuate Nucleus

Hypothalamic region monitoring hunger and satiety hormones.

Homeostasis

Body's process to maintain optimal internal balance.

Caloric Load

Energy content of food influencing eating behavior.

Pleasurable Flavors

Taste preferences linked to high-calorie foods.

Dose

Amount of substance administered in experiments.

Nucleus Accumbens (NAcc)

Brain region involved in motivation and reward.

Mu-opioid receptor

Receptor activated by endogenous opioid neurotransmitters.

Kappa-receptor agonists

Substances that activate kappa-opioid receptors.

U50488H

Kappa-opioid receptor agonist with no significant effects.

Dynorphin

Endogenous opioid that did not affect ingestive behavior.

DAMGO

Mu-opioid receptor agonist increasing sugar consumption.

Hedonic feeding

Eating driven by pleasure rather than hunger.

Endogenous opioid signaling

Neurotransmitter system regulating feeding behavior.

Selectivity of DAMGO

Specific effects of DAMGO on sucrose intake.

Bliss point

Optimal ingredient level for maximum food pleasure.

Ultra-processed foods

Foods engineered to maximize taste and consumption.

Sensory specific satiety

Decreased desire for a specific food after consumption.

Homeostasis

Body's process to maintain optimal physiological conditions.

Hypothalamus

Brain region regulating homeostatic responses.

Ingestive behavior

Actions related to eating and drinking.

Caloric intake

Total calories consumed from food and drink.

Motor activity

Physical movements and actions of an organism.

Sugar water consumption

Increased intake due to DAMGO administration.

Intra-Acb infusion

Direct injection into the nucleus accumbens.

Experimental design

Methodology used to test hypotheses in studies.

Nutrient matching

Equal nutrient content in different diet types.

Weight gain

Increase in body mass due to excess calorie intake.