Module 1: Carbohydrates I Part 1 Flashcards
Anabolism
Building up
Catabolism
Breaking down
Hormones for Anabolism
- Insulin
- Sex Steroids
- Thyroxine & GH (protein)
Hormones for Catabolism
- Glucagon
- Epinephrine
- Glucocorticoids
- Thyroxine & GH (fat & carbs)
What is the metabolic hub?
Acetyle Coenzyme A (Acetyle CoA)
Stages of Metabolism
- Digestion & Hydrolysis
- Degradation
- Oxidation
Stages of Metabolism: 1. Digestion & Hydrolysis
Break down large molecules to smaller ones that enter the bloodstream
Stages of Metabolism: 2. Degradation
Further breaking & some oxidation of molecules to 2- & 3- carbon compounds
Stages of Metabolism: 3. Oxidation
Oxidation of small molecules to CO2 & H2O in the citric acid cycle and electron transport provides energy for ATP synthesis
Monosaccharides
- Simple sugars with multiple OH groups
- Based on number of carbons (3, 4, 5, 6)
- Can be a triose, tetrose, pentose or hexose
Disaccharides
2 monosaccharides covalently linked
Oligosaccharides
2-10 monosaccharides covalently
linked
Polysaccharides
polymers consisting of chains of
> 10 monosaccharides or > 5 disaccharide units
Stachyose
- A constituent of many plants: white jasmine, yellow lupine, soybeans, lentils
- Causes flatulence because humans cannot digest it
Beano
- Contains enzyme alphagalactosidase
- Alphagalactosidase that breaks down oligosaccharides such as stachyose and raffinose
Dextrantriose
A constituent of sake’ and honeydew
Glycemic Index
- How quickly carbohydrates enter the blood stream after intake
- Proteins and fats are not on the glycemic index
- Carbohydrates are chosen 1st for breakdown and metabolism over proteins and fats
Glycemic Load
- How much insulin would need to be released by the pancreas into the blood stream to allow tissues to absorb that specific amount of that specific carbohydrate and reduce blood sugar levels effectively
- BOTH the quality and quantity of the carbohydrate amount in 1 number
What are the ranges of scores for glycemic index?
- Low: 0-55
- Moderate 56-69
- High 70-100
Glycemic Load Equation
100
Blood glucose - exercising muscle (fed or starved)
– Low G6P (being used in glycolysis)
– No inhibition of HK
– High glycolysis from glycogen or blood glucose
Blood sugar in liver - feeding
– Blood glucose concentration high
– GLUT-2 taking up glucose
– Glucokinase induced by insulin
– High cell glucose allows GK to phosphorylate glucose for use by liver
Blood sugar in liver - post-absorptive state
– Blood & cell glucose low
– GLUT-2 not taking up glucose
– Glucokinase not phosphorylating glucose
– Liver not utilizing glucose during post-absorptive state
Blood sugar in liver - starvation
– Blood & cell glucose concentration low
– GLUT-2 not taking up glucose
– GK synthesis repressed
– Glucose not used by liver during starvation
Blood sugar in muscles - feeding and at rest
– High blood glucose, high insulin
– GLUT-4 taking up glucose
– HK phosphorylating glucose
– If glycogen stores are filled, high G6P inhibits HK, decreasing glucose utilization
Blood sugar in muscles - starving and at rest
– Low blood glucose, low insulin
– GLUT-4 activity low
– HK constitutive
– If glycogen stores are filled, high G6P inhibits HK, decreasing glucose utilization
How does low blood sugar affect adipose?
– Stimulates lipolysis and release of fatty acids
