Q 5: CHO Metabolism: Glucose Regulation & Formation Flashcards
What do pancreatic Beta cells produce?
insulin
What do pancreatic alpha cells produce?
glucagon
What is the metabolic fx of pancreas?
release insulin, glucagon, and numerous hormones
what is the name for a pancreatic cell?
islet cell
what is the name for a liver cell?
hepatocyte
what is the name for a muscle cell?
skeletal/smooth/cardiac myocytes
what is the name for adipose tissue cell?
adipocyte
what is the metabolic fx of the liver?
maintains metabolic homeostasis (normalize blood glucose), store glycogen,
synthesize and degrade glycogen, glucose, FA’s, nucleic acids, proteins, and ketone bodies
Generally, what is cellular respiration?
Glucose broken down into ATP
What are three fates of glucose 6-phosphate?
glycolysis/respiration
pentose phosphate pathway
storage of glycogen (glycogenesis)
What are the catabolic pathways?
glycolysis
citric acid cycle
oxidative phosphorylation
glycogenolysis
what are the anabolic pathways?
glycogenesis
gluconeogenesis
What does lactase do?
breaks lactose into galactose and glucose
What does sucrase do?
breaks sucrose into fructose and glucose
what does maltase do?
breaks maltose into glucose
Amylase breaks starch into maltotriose, maltose, or a-limit dextrin (which become glucose)
What happens to glucose molecules after being broken down by enzymes?
transported across the epithelium into blood and transported to the liver
- -becomes energy source
- -stored in liver or adipose tissue
- -glucose transporters move glucose into cells
What benefit does glycogen structure provide over glucose structure in terms of cellular osmolarity?
glucose would pull tons of water to it making it hard to store, glycogen on the other hand doesn’t pull much water
What structure does glucose have intracellularly?
branched glucose homopolysaccharide, glycogen
Glycogenesis pathway (glucose to glycogen)
Glucose –hexokinase–>
glucose 6-phosphate
–phosphoglucomutase–>
glucose 1-phosphate
–UDP-glucose pyrophosphorylase–>
uracil diphosphate-glucose
–glycogen synthase–>
glycogen chain
–glycogen branching enzyme–>
glycogen particle
What two enzymes can work bidirectionally in glycogenesis?
hexokinase and phosphoglucomutase
On which end are new glucose molecules placed by glycogen synthase?
the nonreducing end
How many glucose residues does each chain contain in glycogen?
12-14
What enzyme allows for more storage of glucose in glycogenesis when the glucose residue chain has already reached 12-14 residues?
glycogen-branching enzyme
Where is the only place where glucose 6-phosphatase is located?
in the liver ER
