Week 3 Flashcards
What is the main difference between glycogen and dietary fiber?
Glycogen is digestable
dietary fibre is not digestable
What are simple carbohydrates and what are complex carbohydrates?
simple: monosaccarriade, and disarracaride
complex: olygo and polysaccaride
How is glucose produced in plants?
photosynthesis
What is the role of carbohydrates?
- structure in plants
- source of energy and blood glucose homeostasis
- substrate in the biosynthesis of other compounds
- cell to cell regonition
Whatis a glycoprotein?
a carbohydrate cell receptor
Name the 3 main 6-carbon monosaccharides
Glucose
Frutose
Galactose
Name the 2 3-carbon monosaccharides?
ribose
deoxyribose
Draw the structures of glucose, fructose, and galactose
see notes
How is insulin-dependent glucose uptake by the body?
glucose transporter 4 (GLUT4).
What is galactosemia?
Reduction in the metabolism of galactose to glucose due to deficient galactokinase or other metabolism genes
What are the 3 main disaccharides?
Lactose
Maltose
Sucrose
What is lactose made of?
what glycosidic bonds does it have?
Galactose and glucose
beta 1,4 glycosidic bond
What is Maltose made of?
what glycosidic bonds does it have?
Glucose and glucose
alpha 1,4 glycosidic bond
What is sucrose made of?
what glycosidic bonds does it have?
glocose and frutose
alpha 1,2 glycosidic bond
Lactose intolerance is the inability to digest lactose.
What are the primary and secondary type of lactose intolerance?
Primary:
shortage of the enzyme lactase in
adulthood because of lactase non-persistence, which is the “default” program in humans post weaning
Secondary:
in lactase persistence phenotypes (in certain ethnicities and population with dairy farming ancestry), LI is associated with damage of the lactase producing cells
What are the three main polysaccharides?
starch
glycogen
cellulose
What has a higher GI; amylose or amylopectin?
amylopectin
Are Oligosaccharides digestable?
mostly not
What are the two forms of starch?
Amylopectin and amylose
What is amylose?
continuous chain of glucose molecules
linked by α-1,4 glycosidic bonds
What is Amylopectin?
branched chain of glucose molecules linked by α-1,4 and α-1,6 glycosidic bonds.
Why is amylopectin quicker to digest then amylose?
More quickly digested as more sites available to enzymes activity
What is the glycogen storage capacity in the liver and muscle post meal?
liver: 90-120g in average adult
muscle: 300g
What is glycogen?
storage form of glucose in the human body
How is liver glycogen and muscle glycogen used differently?
Liver glycogen: used for BGL homeostasis principally
Muscle glycogen: substrate for energy production in muscle during exercise
What is glycogen storage disease?
Liver cannot convert glycogen to glucose or glucose to glycogen
What enzymes break down maltose, sucrose and lactose?
Maltose: maltase
Sucrose: sucrase
Lactose: lactase
What can excess glucose lead to?
Excess glucose availability can result in fatty acids via acetyl CoA being diverted to lipogenesis (fed state, high insulin conditions)
How are glucose, galactose absorbed?
active, passive and facilitated
how is fructose absorbed?
facilitated
Liver converts fructose and galactose to intermediates of glycolysis for energy production.
True or false?
true