MBS 217 Lecture 12 Flashcards
Intermediary metabolism
the sum of all intracellular chemical processes by which nutritive material is converted into cellular components
Anabolism:
Energy-requiring process where small molecules joined to form larger molecules
Catabolism:
Energy-releasing process where large molecules broken down to smaller
Essential Materials
Oxygen
Water
Nutrients:
vitamins
mineral ions
organic substrates
Cellular Metabolism
Includes all chemical reactions within cells. Provides energy to maintain homeostasis and perform essential functions
Functions of Organic Compounds
Perform structural maintenance and repairs
Support growth
Produce secretions
Store nutrient reserves
Glycogen:
Most abundant storage carbohydrate
A branched chain of glucose molecules
Triglycerides:
Most abundant storage lipids
Primarily of fatty acids
Proteins:
Most abundant organic components in body
Perform many vital cellular functions
NADH how many electrons and hydrogen molecules
NAD+ is reduced by taking on two electrons but only one hydrogen
Vitamin B3 (green vegetables, tuna, chicken, etc.)
FADH2 how many electrons and hydrogen molecules
FAD is reduced by taking on two hydrogens and two electrons
Vitamin B2 (milk, nuts, red meat, etc.)
Isomer
is a molecule with the same molecular formula as another molecule, but with a different chemical structure.
Phosphorylation
A biochemical process that involves the addition of phosphate to an organic compound
Hydride
hydrogen atom which has an extra electron. This means that it is a negatively charged ion, or anion. That is why Hydride ion (H-) has the minus sign distinguishing it from a regular Hydrogen atom (H).
Glycolysis is also called
Embden-Myerhof Pathway
Hexokinase:
muscle and other tissues
Glucokinase:
liver
What does glycolysis mean?
“splitting sugar”
Takes place in the presence or absence of oxygen
Takes place in the cytosol of cells
Splitting in glycolysis
glucose (6 C sugar) is split into two molecules of the 3 C sugar pyruvate
Glycolysis Factors
Glucose molecules
Cytoplasmic enzymes
ATP and ADP
Inorganic phosphates
NAD (coenzyme)
Products of Glycolysis
- 2 pyruvate
- 2 ATP (net production)
- 2 NADH
Phases of glycolysis
Input of ATP (sugar activation)
Sugar cleavage (fructose 1,6-biphosphate)
NADH production
ATP and pyruvic acid production
Glycolysis Requires Enzymes
Kinases – hexokinase, phosphofructokinase, phosphoglycerokinase, pyruvate kinase
Mutases – phosphoglyceromutase
Dehydrogenases – triose phosphate dehydrogenase (also called glyceraldehyde-3-phosphate dehydrogenase)
Isomerases – phosphoglucoisomerase (also called phosphohexose isomerase), triose phosphate isomerase
Enolase
Aldolase
Pyruvate can be further processed
anaerobically or aerobically
pyruvate anaerobically
lactate
Pyruvate aerobically
completely oxidized to CO2, and H2O generating much more ATP (through the citric acid cycle and electron-transport chain)
lactate is constantly produced from pyruvate via the enzyme
lactate dehydrogenase (LDH) in a process of fermentation during normal metabolism and exercise.
Glycogenesis
Excess glucose used to form glycogen
Lipogenesis
When glycogen stores filled, glucose and amino acids used to synthesize lipids
Glycogenolysis
Breakdown of glycogen to glucose
Gluconeogenesis
Formation of glucose from amino acids and glycerol
