ME03 - Intro to Metabolism Flashcards
Require energy thus endergonic; combine small molecules, such as proteins
Anabolic Pathways
Serve to capture chemical energy in the form of ATP from the degradation of energy_rich fuel molecules; typically oxidative, and require conenzyme (NAD+)
Catabolic Pathways
A group of metabolic reactions with a dual function, providing small metabolites for further catabolism toend products or for use as precursors in synthetic, anabolic reactions eg. TCA cycle
Amphibolic Pathways
What are the Four Stages of Metabolism:
- Hydrolyzed to form monomeric building blocks
- Various pathways transform intermediates to common metabolic intermediate
Acetyl CoA - Acetyl Coa_a_ CO2 (Citric Acid Cycle)
- ATP Synthase (Oxidative
phosphorylation)
Explain Absorptive state.
The pancreas is stimulated by the high concentration of glucose to release insulin into the blood stream
_ Insulin activates the liver to transport glucose into the liver cells. Insulin activates glycolysis to generate ATP.
_ Once liver glycogen reaches its maximum, excess glucose is diverted towards triacylglycerols.
_ The liver synthesizes both fatty acids and the glycerol from glucose.
_ Triacylglycerides are not normally stored in the liver. They are packaged with lipoproteins, phospholipids and cholesterol to form VLDLs which are released into the blood stream. Some of the fatty acids of the VLDL are taken up by the tissues, but most end up being stored in the adipose tissue.
_ Insulin activates the uptake of glucose. Insulin also stimulates the adipose to tissue to absorb the fatty acids carried by the VLDLs. The adipose tissue needs glucose to generate glycerol to produce triacylglycerols
Important enzymes in TCA
*Cindy Is Kinky So She Fornicates More OftenCitrate, Isocitrate, alpha_Ketoglutarate, Succinyl_CoA, Succinate, Fumarate, Malate, Oxaloacetate
Final pathway where oxidative catabolism of
carbohydrates, amino acids and fatty acids converge, their carbon skeletons being converted to CO2
TCA Cycle/Krebs cycle/ Citric Acid Cycle
_ Occurs in the mitochondria Oxidation provides energy for the production of the majority of ATP
_ Occurs in the mitochondria
The conversion of glucose to Pyruvate
Glycolysis
A process in which the NADH and [FADH2] produced during glycolysis, __oxidation, and other catabolic processes are oxidized thus releasing energy in the form of ATP
ETC
_ Located in the inner mitochondrial membrane
_ Final common pathway by which electrons derived
from different fuels of the body flow to oxygen
ETC
In ETC, what is the final electron acceptor
Oxygen
Inability of insulin to go into our tissue Causes thirst, excess urination, hunger,
thinning, blurred vision
Diabetes
Explain POST-ABSORPTIVE STATE
_ After a meal, blood glucose level begins to fall.
_ The insulin concentration also begins to fall and
the glucagon concentration begins to rise.
_ Glucagon stimulates glycogenolysis, the break down of liver glycogen to maintain the blood glucose concentration. Glucagon also stimulates gluconeogenesis, synthesizing glucose from
lactate, alanine, and glycerol.
_ The liver glycogen stores are depleted, and
gluconeogenesis is generating all of the blood glucose. Only the glycerol moiety of triacylglycerols can be used as source of glucose. Glucagon also stimulates the break down of proteins and the catabolism of amino acids.
_ This generates ammonia, which the liver converts into urea to be excreted.
_ During fasting, the triacylglycerols stored in the adipose tissue become the major energy source.
The glycerol component is used for gluconeogenesis and the fatty acids released are oxidized by tissues such as muscle and heart tissue.
_ The liver absorbs these fatty acids and converts
them into ketone bodies, which are released in the blood. These ketone bodies can fuel the muscles and heart saving glucose for the brain.
Storage form of carbohydrates but inefficient
Glycogen
riglyceriede; cannot be transported (hydrophobic), _ Becomes VLDL (Very low density lipoprotein)
Fat
