TJ SG Flashcards
Committed Step
The first irreversible step unique to a pathway
Distinguishing features of anabolic and catabolic pathways
Must Be: linked Regulated Enzyme Catalyzed Irreversible
What coenzymes are associated with the following vitamins:
- Riboflavin
- Thiamin
- Vitamin B12
- Niacin
- Folic Acid
- FADH and FADH2
- Thiamin Phosphate
- Cyanobolamine
- NADH
- Tetrahydrofolate
What are the stages in energy extraction from foodstuffs?
- macromolecules broken down to monomers
- Oxidation of monomers to Acetyl CoA with limited ATP formation
- Complete Aerobic Oxidation of acetyle CoA to CO2 and H2O with the formation of ATP in the mitochondria
How does the glucose oxidase assay work?
- HIGHLY specific for Glucose
- forms gluconic acid and H2O2
- H2O2 reacts with an organic chromagen to from a colored product
How does the Hexokinase assay work?
- Gold Standard
- Uses G6 dehydrogenase
- amount of NADPH produced is measured at 340 nm
What accounts for decrease in blood glucose between eating and two hours?
Glucose Uptake
What accounts for stabilization of blood glucose after 2 hours and beyond?
Release of Glucose by the liver
T or F: when you digest food the osmolarity is higher in the lumen, which pulls H2O into the lumen
True
What is the difference between paracellular and transcellular movement of fluid?
Transcellular - through the cell
Paracellular - beside the cell
Does water ever undergo facilitated diffusion?
Yes, through aquaporins
What is the difference between moving in amino acids and di and tripeptides?
both use sodium cotransport, however Di and Tri peptides use an H+ dependent contransport mechanism
What does emulsification do to fats and how does this facilitate their entry into the apical surface of epithelial cells?
- Emulsification by bile salts causes monoglyceride formation from fatty acids.
T or F: Ca2+ has a major passive diffusion paracellular transport pathway in the duodenum and jejunum
True
What type of transport is exemplified by calcium rushing in via voltage dependent calcium channels?
Secondary Active transport