Chapter 7 Flashcards
What is the main source of energy for the mammalian brain?
- glucose!
- (neurons have highest energy demand)
Distinguish homeostatic vs hedonic motivation to consume food
- homeostatic: energy balance
- hedonic: highly palatable foods
Stress-related changes in eating are usually related to (homeostatic/hedonic) control
hedonic!
What is the prandial state?
- after consuming a meal
- anabolism
- blood is filled w nutrients
- energy stored as glycogen and triglycerides
What is the postabsorptive state?
- fasting condition
- catabolism
- glycogen and triglycerides broken down to be used as fuel
Well-fed animals have:
- high blood conc of ___, ___, ___, and ___
- high stores of ____ and ____
- high ___ enzymes
- high ___, ___, and ___
Word bank:
- glucose, glucagon, insulin, leptin, glucocorticoids, amino acids
- free fatty acids, body fat in adipose tissue, glycogen in liver
- lipolytic enzymes, lipogenic enzymes, ketone bodies, circulating ghrelin
- CCK, NPY, melanin-concentrating hormone, a-melanocyte-stimulating hormone, orexin, corticotropin-releasing factor, cocaine/amphetamine regulated transcript, catecholamines
- high blood conc of glucose, amino acids, insulin, and leptin
- high stores of body fat in adipose tissues and glycogen in liver
- high lipogenic (fat-synthesizing) enzymes
- high CCK, a-melanocyte-stimulating hormone, and cocaine and amphetamine regulated transcript
Fasting animals have:
- high blood conc of ___ and ___
- high ____
- high ___ enzymes, ___, and ___
- high ___, ___, ___, ___, and ___
Word bank:
- glucose, glucagon, insulin, leptin, glucocorticoids
- free fatty acids, body fat in adipose tissue, glycogen in liver
- lipolytic enzymes, lipogenic enzymes, ketone bodies, circulating ghrelin
- CCK, NPY, melanin-concentrating hormone, a-melanocyte-stimulating hormone, orexin, corticotropin-releasing factor, cocaine/amphetamine regulated transcript, catecholamines
- high blood conc of glucagon and glucocorticoids
- high free fatty acids
- high lipolytic enzymes, ketone bodies, and circulating ghrelin
- high NPY, melanin-concentrating hormone, orexin, corticotropin-releasing factor, and catecholamines
What are orexigenics and anorexigenics?
- orexigenic: appetite stimulant
- anorexigenic: reduces appetite
During the postabsorptive phase, ___ secretion rises while ____ secretion falls
insulin; glucagon
Metabolism during the well-fed state:
- conversion of ___ to ___ in liver
- ___ is stored in liver and muscle
- ___ facilitates transport of glucose and amino acids into into muscle and fat cells
- conversion of amino acids to ___ in liver
- conversion of glucose to glucagon in liver
- glycogen is stored in liver and muscle
- insulin facilitates transport of glucose and amino acids into into muscle and fat cells
- conversion of amino acids to ketone bodies in liver
Metabolism during the fasting state:
- ___ are formed which can be used by brain when glucose is scarce
- ___ is released from the pancreas
- ____ breaks down stored glycogen in liver
- ____ in adipose tissue releases free fatty acids and glycerol
- ketones are formed which can be used by brain when glucose is scarce
- glucagon is released from the pancreas
- glycogenolysis breaks down stored glycogen in liver
- lipolysis in adipose tissue releases free fatty acids and glycerol
What is glycogenolysis?
- breakdown of stored glycogen in liver or muscles to provide steady supply of glucose for energy
- during fasting state
What is lipolysis?
- breakdown of adipose tissue into free fatty acids
- during fasting state
What is gluconeogenesis?
- production of glucose from amino acids
- occurs in liver in response to mild fasting
- during fasting phase
Type 1 diabetes can be characterized as insulin-(resistant/dependent) while type 2 as insulin-(resistant/dependent)
type 1 = dependent
type 2 = resistant
Distinguish type 1 and type 2 diabetes
TYPE 1
- beta c of pancreas destroyed by immune system
- less insulin so less glucose absorbed and more glucose in blood
- genetic, early onset, more rare
- managed by insulin injections
- INSULIN DEPENDENT
TYPE 2
- pancreas prod enough insulin but c are not responsive to it so glucose stays in blood
- lifestyle related, 80-90% of all diabetes
- INSULIN RESISTANT
(T/F) usually obesity PRECEEDS increased food intake
TRUE!!
Leptin is produced by ____ and circulates in concentrations proportional to ____. High levels signal (satiety/starvation)
adipose cells, proportional to total amount of fat in body
high levels signal satiety!
Why can’t we use leptin as a treatment for human obesity?
- bc they don’t lack leptin, more like leptin resistance
High levels of leptin (increase/decrease) appetite and (increase/decrease) energy expenditure
decrease appetite; increase energy expenditure
What role do insulin receptors play in metabolism? Where are they located?
- monitors of metabolic fuels (eg glucose levels in brain)
- located in brain (esp arcuate nuclei)
Insulin concentrations act similarly to (leptin/ghrelin), and (increase/decrease) with higher food intake
leptin; increase
Ghrelin (increases/decreases) food intake
increases
when do blood concentrations of ghrelin peak?
around time of meal onset
