Review 9 Flashcards
Short and Long Fatty acids Absorption
- Short-chain fatty acids are absorbed across the intestine into the blood.
- Long-chain fatty acids are absorbed as micelles and assembled into chylomicrons for release into lacteals of the LYMPHATIC system and re-enter the bloodstream via the thoracic duct.
Hormone-sensitive lipase of Adipocytes Regulators
- Inhibitors - Insulin
2. Activators - Epinephrine and Cortisol
HDL function
Picks up cholesterol accumulating in blood vessels Delivers cholesterol to liver and steroidogenic tissues.
LDL Function
Delivers cholesterols into cells.
Cholesterol Metabolism Notes
- HMG-CoA reductase
- Activator - Insulin
- Inhibitor - Cholesterol
Fatty Acid Notes
- Occurs in liver and stimulated by Insulin.
2. Synthesized in the CYTOPLASM from acetyl-CoA transported from MITOCHONDRIA.
Citrate Lyase
Splits citrate into acetyl-CoA and oxaloacetate.
Fatty Acid Synthesis Acetyl-CoA carboxylase
- Rate limiting enzyme.
- Adds CO2 to acetyl-CoA to form malonyl-CoA
- Requires Biotin and Citrate.
- Activator - insulin and ATP
Fatty Acid Beta Oxidation
- Activator - Glucagon
2. Inhibitor - Insulin
Fatty Acid Beta-Oxidation Notes
- Occurs in mitochondria (some B-oxidation in peroxisome)
- Activation: fatty-acyl-CoA synthetase attaches fatty acid to CoA
- Fatty acids Transported into MITOCHONDRIA by the carnitine shuttle
- Short-chain fatty acids (two to four carbons) and medium-chain fatty acids (six to twelve carbons) diffuse freely into mitochondria. Long-chain fatty acids (14 to 20 carbons) require transport via a carnitine shuttle.
- β-oxidation uses cycles of oxidation, hydration, oxidation, and cleavage
- Releases acetyl group and produces 1 FADH2 and 1 NADH.
LOOK AT DIAGRAM OF BETA-OXIDATION
PLEASE :-)
Ketogenesis vs. Ketolysis
Ketogenesis - Ketones form during a prolonged starvation state due to excess acetyl-CoA in the liver.
Ketolysis - Regenerates acetyl-CoA for use as an energy source in peripheral tissues.
Triglycerides Catabolism
- A 16 carbon fatty acid is cleaved 7 times and produces 7 FADH2 and 7 NADH as it is converted into 8 acetyl-CoA.
- Acetyl CoA enters into the Krebs cycle as usual.
- Glycerol backbone is converted into PGAL and used in glycolsis.
Homeostasis
- A physiological stable state that is maintained and adjusted, often with the expenditure of energy.
- Usually different from equilibrium
- Nervous tissue and red blood cells are INSENSITIVE to insulin and both tissues derive energy almost exclusively from GLUCOSE. Also, the nervous tissue may also use KETONES.
Insulin Notes
- Secreted by pancreatic BETA cells.
2. Increases the rate of anabolic metabolism.
Carbohydrates and Insulin
- insulin INCREASES the uptake of glucose and INCREASES carbohydrate metabolism in muscle and fat cells.
- Insulin INCREASES glycogen synthesis in the liver by increasing the activity of GLUCOKINASE and GLYCOGEN SYNTHASE while DECREASING the activity of enzymes that promote glycogen breakdown (GLYCOGEN PHOSPHORYLASE and GLUCOSE-6-PHATASE).
Glucagon Notes
- Secreted by pancreatic ALPHA cells
2. Activator - Low glucose and high protein.
Glucagon and Glucose
- INCREASES liver glycogenolysis, ACTIVATES glycogen phosphorylase and INHIBITS glycogen synthase.
- INCREASES liver gluconeogenesis. INCREASES the conversion of pyruvate to phosphoenolpyruvate by PYRUVATE CARBOXYLASE and PHOSPHOENOLPYRUVATE CARBOXYKINASE (PEPCK).
- INCREASES the conversion of fructose 1,6-bisphosphate to fructose 6-phosphate by fructose-1,6-bisphosphate.
- Increases liver ketogenesis and DECREASES lipogenesis.
- INCREASES lipolysis in the liver. Glucagon INCREASES hormone-sensitive lipase in the liver.
- Glucagon is not considered a major fat-mobilizing hormone.
LEARN INSULIN AND GLUCAGON RELATIONSHIP
Look at the handout
Glucocorticoids
- Increase blood glucose in response to stress (including exercise, cold, and emotional stress) by BREAKING DOWN fat stores, INCREASING gluconeogenesis and DECREASING glucose uptake.
Catecholamines
- INCREASE glycogenolysis and lipolysis -> INCREASE basal metabolic rate through their SYMPATHETIC nervous system activity..
- INCREASE the activity of liver and muscle glycogen phosphorylase.
Thyroid Hormone
- INCREASE basal metabolic rate.
- T3 is more potent than T4 (thyroxine) but have a shorter half-life.
- T4 is converted to T3 in tissues.
Hypothyroidism
Cold intolerance, fatigue, weight gain, and depression
Hyperthyroidism
Weight loss, anxiety, jitteriness, and fever
Glucose Synthesis Source
Lactate
Glycerol
Amino Acids
Fast-twitch muscles
Fast-twitch muscle fibers have a high capacity for anaerobic glycolysis but are quick to fatigue. They are involved primarily in short-term, high-intensity exercise.
Slow-twitch Muscles
Slow twitch muscle fibers in arm and leg muscles are well vascularized and primarily oxidative. They are used during prolonged, low-to-moderate intensity exercise and resist fatigue.
Ghrelin and Orexin Function
- Secreted by the stomach. Sight, sound, taste, and especially smell all act as signals for their release.
- Increases appetite.
Leptin
- Hormone secreted by fat cells
- Decreases appetite.
- Lipids are the primary factor in the gradual change of body mass over time.
Calorimetry
Can measure basal metabolic rate based on heat-exchange with the environment.
Respirometry
Measures O2 consumption and CO2 release
Consumption tracking
Measurement of blood concentrations of substrates and hormone (glucose, thyroid hormones, and thyroid-stimulating hormone, insulin, glucagon, oxygen, and carbon dioxide).
Skeletal Muscle and Functioning
An active muscle may use anaerobic metabolism, oxidative phosphorylation of glucose, direct phosphorylation from creatine phosphate, or fatty acid oxidation, depending on fiber type and exercise duration.
Hell-Voland Zelinsky (HVZ)
- Method of bromination with Br2, PBr3, and H2O.
2. It is method to synthesize alpha amino acids.
Reactivity of the carboxylic acids and its derivatives
- Acid Chlorides > Anhydrides > Ester > Amides (Induction reduces and resonance increases)
Induction vs. Resonance
Induction is electron-withdrawing from electronegative
Resonance stabilizes electron and spread of electron density. It competes with induction.
Nucleophilic acyl substitution
- Addition of a nucleophile to a carboxylic acid or its derivative (even carbonyl directly to its C).
End result - substitution of Nucleophile for Y group
How do substituents affect reactivity?
- Acyl chlorides contribute to reactivity for example.
- Steric effects - If R = tert-butyl; nucleophile will not affect.
- Nucleophile needs to be strong.
- Need a LG that is stable. Those with -1 are very stable.
Acid vs. Base Catalyzed Ester hydrolysis Products
Carboxylic acid with the H in acid-catalyzed, while carboxylic acid without the H in base-catalyzed.
Beta-Lactam and Bacteria
Beta-lactam is an amide in a ring. The mechanism of action involves the breakage of the ring and attaching to the carbonyl carbon
Unit of K in zeroth, 1st, and 2nd Order
Zeroth - M/S
1st - 1/s
2nd - 1/M.S
1st Order Equation Graph, shape, and Slope
Straight line with negative slope
Half-life 1st Order Equation Graph, shape, and Slope
Negative Slope Slope turning into U
2nd Order Equation Graph, shape, and Slope
Positive straight line slope with a coefficient depending on 1/A0
Half-life 2nd Order Equation Graph, shape, and Slope
Negative slope slanting turning into U
Difference between half-life k of 2nd order and 1st Order
k of 2nd order depends on A0 while k for 1st order half-life k is independent on anything
3 Conditions for Reaction to occur
- Molecules must collide to react
- Collisions must have the correct orientation
- Collisions must have enough energy
Formula for k with Arrhenius equation
Ae^(-Ea/RT)
2 other forms of k equation
- lnk = (-Ea/R)(1/T) + lnA
2. lnk2/k1 = (-Ea/R)(1/t2 - 1/t1)
First Order formula and Half-life
ln[A]t = -kt + ln[A]0
Half-life: 0.693/k
Second Order formula and Half-life
1/[A]t = kt + 1/[A]0
Half-life: 1/[A]0 *1/k
Zeroth Order formula and Half-life
[A]t = -kt + [A]0 (-ve slope)
Half-life: [A]0/2k
Regioselective
Look at the products and the different isomers it forms of the product
Stereoselective
Forms stereoisomers (usually enantiomers)
Stereospecific
Depends on the isomers of the reactant
Hoffman Product
Less substituted product
Zaistev’s Rule
H is lost from the carbon with the least Hs because it can be easily stabilized.
Markovnikov
H is added to the most substituted Carbon while anti-markovnikov is vice-versa
Anti-Peri-planar concept
H is axial and also axial to the chlorine or leaving group
Zaistev Product
More substituted product
Kinetic vs. Thermodynamic
Kinetics:
- Forms fastest
- Less substituted and less stable
- Because steric and higher number of H
- Low temperature
- Large base
Thermodynamics:
- Most Stable
- Forms slowly
- High temperature
- Small base
- Most substituted
Aldehyde/Ketone plus alcohol with heat/without heat
With heat = Alkene and aldehyde or ketone together where it is trans
Without heat - Alcohol together joined with ketone or aldehyde
Intramolecular Aldol Condensation
Alcohol, heat without any additional other ketone or something to attach to it. Also, I think length plays a big role. So I guess without water like other.