Chapter 6

Question 1

Arcuate Nucleus (ARC)

Answer 1

master hypothalamic centre for food intake control
- main part of hypothalamus

Question 2

NYP/ AgRP

Answer 2

increase eating and reduce metabolism by releasing these peptides

Question 3

POMC Neurons

Answer 3

decrease eating; release POMC and activate neurons that make you feel full therefore decreasing eating
- also glutamate

Question 4

GABA

Answer 4

increases eating

Question 5

Lateral Hypothalamus

Answer 5

brain region that initiates eating and controls aspects of feeding behaviour and metabolic responses
- gastric juice secretion
- insuline production
- process reward value of different food and how palatable different foods are

Question 6

Orexin

Answer 6

increase eating and wakefullness in response to food deprivation
- excites the NPY neurons and inhibits the POMC neurons

Question 7

Paraventricular Nucleus

Answer 7

regulate eating and metabolic process
- body temp, fat storage and cellular metabolism
- POMC stimulate this and that causes a reduction in eating
- NYP and AgRP inhibit this

Question 8

Ventromedial Hypothalamus

Answer 8

brain region that reduces satiety and increase metabolism
- only receives info from POMC

Question 9

Ghrelin

Answer 9

orexigenic peptide hormone synthesized in the stomach and released into bloodstream during fasting
- increases eating
- stimulates growth hormone release
- anticipatory hormone; released before each meal and drops immediately after you begin eating

Question 10

Cholecystokinin

Answer 10

peptide hormone that is best known satiety signal, released by stomach and small intestine as food passes into duodenum
- limits mean size and aids digestion
- does not reduce total food intake

Question 11

PYY

Answer 11

released in the intestine in response to food, suppressing appetite over longer period of time
- increased PYY, decrease total food intake

Question 12

Leptin

Answer 12

peptide hormone secreted by fat cells that inhibits eating
- reduce meal size and total daily intake

Question 13

BMI

Answer 13

quantifier of leanest or obesity calculated by dividing persons weight in kilograms by squared height in meters
- increased health risks; diabetes, high blood pressure, heart disease, stroke, cancer , alheizmers, shorter life spans
- cannot be characterized by lack of impulse control, inability to delay gratification, or maladaptive eating style
- factors that lead to obesity are common to the ones that lead to drug addiction

Question 14

Obesity Gene

Answer 14

gene on chromosome 6 linked to obesity in mice, signified as ‘ob’
- recessive gene

Question 15

Diabetes

Answer 15

gene on chromosome 4 linked to obesity in mice, signified as db
- recessive gene

Question 16

Epigenetic

Answer 16

modifications to DNA that turn genes ‘on; or ‘off’ without changing dene’s DNA sequence

Question 17

Methylation

Answer 17

attach methyl group to gene, which makes it difficult for a gene to function

Question 18

Sleep Deprivation

Answer 18

plays a role in weight gain
- this is because when you are awake, your body is producing orexin which increases hunger

Question 19

Basal Metabolism

Answer 19

energy required to fuel brain and other organs and to maintain body temperature
- metabolism will increase or decrease in order to defend a set joint weight
- goal of 10% weight reduction can be more practical than return to normal weight
- 10% reduction also associated with reduced risk for chronic disease

Question 20

Anorexia

Answer 20

historical; cases dating back 300 years ago
- 56% heritability

Question 21

plays a role in understanding eating disorders

Answer 21

Serotonin and Dopamine
- so largely involved in mood disorders and eating so we believe it plays
- using anti-depressants increases serotonin and decreases food binges for bulimia
- dopamine brings back the reward circuit for food making you feel good

Question 22

Bulimia

Answer 22

up to 84% heritability

Question 23

Motivation

Answer 23

set of factors that initiate , sustain, and direct behaviours
- unable to be explained solely in terms of outside stimuli

Question 24

Instinct

Answer 24

complex behaviour that is automatic, unlearned, and unmodifiable occurring in all members of a species
- migration and parental behaviour in animals
- relying more on instinct less on learned behaviour

Question 25

drive theory

Answer 25

body maintains condition of homeostasis

Question 26

Homeostasis

Answer 26

the state in which any particular system is in balance or equilibrium

Question 27

drive

Answer 27

an aroused condition

Question 28

Incentive Theory

Answer 28

people motivated by external stimuli, not just internal needs

Question 29

Arousal Theory

Answer 29

people behave in ways that keep them at preferred level of stimulation

Question 30

Set Point

Answer 30

point of homeostasis for system to return to 37 degrees celsius

Question 31

Ectothermic Animals

Answer 31

rely on certain behaviours to maintain body temperature - lizards and snakes

Question 32

Endothermic Animals

Answer 32

use energy reserves as well as environment to maintain a body temperature - birds and mammals

Question 33

Preoptic Area

Answer 33

brain area in mammalian hypothalamus that contains separate warmth-sensitive and cold-sensitive cells - ex. tells body to shiver to warm up

Question 34

Thirst

Answer 34

dry mouth and throat influence when to drink, not how much to drink

Question 35

Hypovolemic Thirst

Answer 35

condition of thirst occurring when blood volume drops due to loss of extracellular water - often singled by baroreceptors

Question 36

Osmotic Thirst

Answer 36

condition of thirst occurring when fluid content decreases inside body cell - outside environment is too salty

Question 37

Subfornical Organ (SFO)

Answer 37

brain structure adjacent to third ventricle that sense and regulates internal water balance with OVLT

Question 38

Organum Lamina Terminalis (OVLT)

Answer 38

brain structure adjacent to third ventricle that senses and regulates internal water balance with SFO

Question 39

Circumventricular

Answer 39

outside blood-brain barrier with direct access to blood circulation - SFO and OVLT

Question 40

Osmoreceptor

Answer 40

fires more as volume decreases due to fluid loss