FNDH 620 Exam 2 Questions and Answers |Complete Solutions Graded A+ |100% Correct
Describe the transitional nature of the metabolic states - Metabolic states overlap due to
shifting concentrations of hormones
- Many metabolic intermediates are crossroads between energy pathways & metabolic states.
How does the insulin:glucagon ratio affect different metabolic pathways under normal (non-
exercise) conditions insulin:
Decreased muscle protein catabolism
Fatty oxidation stops
Glucose oxidaition
Glucagon:
Opposite
- If insulin is higher, then more glucose will be taken up
- If glucagon is higher, then less glucose will be take up
What is the importance of increased glucose-6-phosphate concentration formed during early
refeeding? Maintain gradient
Net effect of intermediate-long fed state on blood glucose (normal circumstances) Blood
glucose levels decrease
Hormones highest in post-fed and fasting states post-fed: insulin
fasting: Glucagon
Fed State, AKA - Postprandial State •Ingested food absorbed into either the hepatic portal
vein or the lymphatic system.
,•Liver removes half of glucose and amino acids, and removes almost all galactose and fructose
during the first pass
•Remaining glucose and AA go to circulation and stimulate insulin release
Fasting State •Begins several hours after a meal
•Blood glucose levels slowly shift toward Hypoglycemia
•Catabolic effects of glucagon become prominent
•Glucose in the blood is provided from energy stores
•Increased use of alternate energy substrates throughout the body
•Glycogen stores are liberated
•Gluconeogenesis increases
Starvation •Fasting beyond 1 day
•Hepatic glycogen stores become exhausted (24-36 hours)
--Can no longer be used as energy source
•Skeletal muscle amino acids and other gluconeogenic precursors become important
•Production of ketone bodies increases as more and more fatty acids are mobilized and
oxidized in the liver
•Ketone bodies become major energy source for brain/skeletal muscle after longterm
fasting/starvation
•Body adaptation - more ketones are used and protein is spared
Approximate water content of body fat vs. fat free mass Fat-free mass (lean muscle etc) has
more water content than than fat.
Effect of increased skeletal muscle on RMR Increases RMR
, Hydrostatic or Underwater Weighing - body density can be determined by dividing body wt
on land by body wt under water & accounting for residual air
Air Displacement (Bod Pod) an egg-shaped chamber that uses air displacement to determine
total body volume, total body density, and percent body fat
Duel Energy X-Ray Absorptiometry (DEXA) - measures FM, FFM, & bone mineral mass
- allows est. of osteoporosis risk
- less radiation than a normal x-ray
- quick and easy
- large and costly
Skinfold Assessment Assesses subcutaneous fat deposits, limb circumference, and skinfold
thickness.
- assumes direct relationship b/w subcutaneous fat and TBF
- assumes skin and fat thickness & compressibility is uniform all over body
- skin thickness is negligible & constant
Bioelectrical Impedance Analysis (BIA) A method of assessing body composition by running a
low-level electrical current through the body.
Influence of leptin, ghrelin, CCK and NPY on appetite Increase Appetite:
- Ghrelin
- Insulin
Decrease Appetite:
- Leptin
Describe the transitional nature of the metabolic states - Metabolic states overlap due to
shifting concentrations of hormones
- Many metabolic intermediates are crossroads between energy pathways & metabolic states.
How does the insulin:glucagon ratio affect different metabolic pathways under normal (non-
exercise) conditions insulin:
Decreased muscle protein catabolism
Fatty oxidation stops
Glucose oxidaition
Glucagon:
Opposite
- If insulin is higher, then more glucose will be taken up
- If glucagon is higher, then less glucose will be take up
What is the importance of increased glucose-6-phosphate concentration formed during early
refeeding? Maintain gradient
Net effect of intermediate-long fed state on blood glucose (normal circumstances) Blood
glucose levels decrease
Hormones highest in post-fed and fasting states post-fed: insulin
fasting: Glucagon
Fed State, AKA - Postprandial State •Ingested food absorbed into either the hepatic portal
vein or the lymphatic system.
,•Liver removes half of glucose and amino acids, and removes almost all galactose and fructose
during the first pass
•Remaining glucose and AA go to circulation and stimulate insulin release
Fasting State •Begins several hours after a meal
•Blood glucose levels slowly shift toward Hypoglycemia
•Catabolic effects of glucagon become prominent
•Glucose in the blood is provided from energy stores
•Increased use of alternate energy substrates throughout the body
•Glycogen stores are liberated
•Gluconeogenesis increases
Starvation •Fasting beyond 1 day
•Hepatic glycogen stores become exhausted (24-36 hours)
--Can no longer be used as energy source
•Skeletal muscle amino acids and other gluconeogenic precursors become important
•Production of ketone bodies increases as more and more fatty acids are mobilized and
oxidized in the liver
•Ketone bodies become major energy source for brain/skeletal muscle after longterm
fasting/starvation
•Body adaptation - more ketones are used and protein is spared
Approximate water content of body fat vs. fat free mass Fat-free mass (lean muscle etc) has
more water content than than fat.
Effect of increased skeletal muscle on RMR Increases RMR
, Hydrostatic or Underwater Weighing - body density can be determined by dividing body wt
on land by body wt under water & accounting for residual air
Air Displacement (Bod Pod) an egg-shaped chamber that uses air displacement to determine
total body volume, total body density, and percent body fat
Duel Energy X-Ray Absorptiometry (DEXA) - measures FM, FFM, & bone mineral mass
- allows est. of osteoporosis risk
- less radiation than a normal x-ray
- quick and easy
- large and costly
Skinfold Assessment Assesses subcutaneous fat deposits, limb circumference, and skinfold
thickness.
- assumes direct relationship b/w subcutaneous fat and TBF
- assumes skin and fat thickness & compressibility is uniform all over body
- skin thickness is negligible & constant
Bioelectrical Impedance Analysis (BIA) A method of assessing body composition by running a
low-level electrical current through the body.
Influence of leptin, ghrelin, CCK and NPY on appetite Increase Appetite:
- Ghrelin
- Insulin
Decrease Appetite:
- Leptin
