Chapter 9 HARDEST ONE:( Flashcards
What is metabolism?
The sum of all chemical and physical processes by which the body breaks down and builds up moles.
Metabolic Pathways are
a group of bio chemical reactions that occur in progression from beginning to end.
Intermediates are..
compounds formed along way in a pathway.
What is Anabolism?
Making new molecules from smaller ones. Building up. Requires energy.
What is Catabolism?
breakdown of larger complex molecules into smaller more basic ones. During digestion, chemical reaction break down proteins lipids and carbs. releases energy.
ATP
the body’s source of immediate energy. it happens when a phosphate bond is broken and energy is released.
ADP
cells break high phosphate bond from ATP. results in ADP and a free P.
AMP
hydrolysis of ADP.
ATP synthesis depends on…
the transfer of electrons in a series of reactions from energy yielding compounds to oxygen.
Oxidized substances…
gain oxygen, loses electron and hydrogen
Reduced substances….
lose oxygen, gain electron and hydrogen.
What controls redox reactions?
enzymes
What are known as coenzymes?
vitamins.
Mitochondria is..?
is the site of energy production in the cell. POWERHOUSE!!
Cellular Respiration is the
process of obtaining energy in order to make ATP molecules.
Aerobic…
with oxygen, efficient
Anaerobic
little or no oxygen, not as efficient. example: Fermentation.
What are the 4 stages of Cellular Respiration of Glucose?
Glycolysis, Transition Reaction, Citric Acid Cycle, Electron Transport Chain.
Glycolysis is when
glucose is converted to pyruvate which produces NADH +H+. in the cytosol cell.
Transition Reaction is when…
pyruvate is oxidized and joined with CoA, which produces acetyl CoA and NADH + H+ releasing CO2 as waste. this happens in mitochondria.
Citric Acid Cycle is when…
Acetyl CoA enter cycles producing NADH + H+, FADH2, ATP and CO2. this happens in mitochondria.
Electron Transport Chain is when…
NADH + H+ and FADH2 are oxidized in to NAD+ and FAD. happens mitochondria. at the end O combines with H to form water. here is where most ATP are formed.
Anaerobic Glycolysis
happens in cells with no mitochondria or oxygen. pyruvate is converted to lactate/lactic acid. Lactate is picked up from the liver. The liver will synthesize compounds used in aerobic metabolism.
NOT AS EFFICIENT AS AEROBIC!
Lipolysis
Dietary and Adipose Triglyceride. broken down into 3 fatty acids and 1 glycerol.
Free Fatty Acids are used for
energy or stored
Beta oxidation is when
fatty acids are transported to working cells needing energy. Long chain fatty acids are broken down into 2 carbon segments that lead to the formation of acetyl CoA.
CHO Aids Fat Metabolism
ocaloacetate needed to combine with acetyl CoA to enter CAC. because the CAC has to many functions, the production of oxaloacetate may not be able to keep up with Beta oxidation.
Ketone bodies are formed by
imcomplete fatty acid oxidation.
Ketogeneis is mainly with
hormonal imbalances. The build up of ketones are converted back to acetyl CoA and is excreted through the lungs.—Fruity breath!
Ketosis is found in (what types of people/diseases)?
Type 1 Diabetes, semi starving or fasting.
What happens in ketosis?
as ketone bodies increase, glucose decreases. it reduces the need for the liver and kidney to produce glucose from AA or glycerol. spares a body protein as fuel sources.
Death will occur in ketosis when…
half the body protein is depleted. point of no return! about 50-70 days of fasting!
Fasting encourages what? (4 things)
Glycogen breakdown, fat breakdown, gluconeogenesis, synthesis of ketone bodies
Feasting encourages what? (4 things)
Glycogen synthesis, fat synthesis and storage, protein synthesis, urea synthesis
Stored energy can be used during which 3 times?
Sleep, fasting, or exercise
Extra energy is stored as carbohydrates in what amount and as what?
Limited amounts as liver and muscle glycogen
Extra energy is stored as fat (trigylercides) in what amount size?
Unlimited
The body has no mechanism for storing which two things?
Amino acids, nitrogen
What is gluconeogenesis?
Making glucose from non-glucose substances
Gluconeogenesis PRIMARILY comes from what?
Amino acids
Gluconeogenesis derives SMALL amounts from what?
Glycerol
Gluconeogenesis maintains blood glucose during which 4 activities?
Sleep, fasting, illness, exercise
______ ______ for glucose production can draw on vital tissue proteins (skeletal and heart muscles and organ proteins)
Protein catabolism
What is lipogenesis?
Making fat from nonfat substances such as carbohydrates, amino acids, and alcohol
Lipogenesis occurs when?
Consuming excess calories beyond burn
In lipogenesis, acetyl CoA units assemble into what?
Fatty acid chains
In lipogenesis, fatty acids combine with glycerol to form what?
Triglycerides
Lipogenesis mostly occurs where in the body?
Liver cells
What is amino acid synthesis?
The body makes the carbon skeleton of nonessential amino acids
In amino acid synthesis, the amino group comes from what?
Transamination
Synthesis of NEAA (non-essential amino acids) occurs only when the body has enough what?
Energy and nitrogen
In amino acide synthesis, since essential amino acids CANT be synthesized, they must be what?
Consumed
What is the primary anabolic hormone?
Insulin
The body prefers using what for energy
Carbohydrates and fat
Protein is reserved for
metabolic function that cannot be performed by others (building and repair body tissues)
What is used to fuel primarily low total energy or carb intake?
protein
Protein metabolism happens where?
primarily in the liver.
Deamination is the…
loss of amino group from an amino acid. it requires Vitamin B6. Carbon skeleton is left to enter CAC as Acetyl CoA
Glucogenic Amino Acids contain
carbons that can become C’s of glucose. Any part of the skeleton can form pyruvate or bypass Acetyl CoA and enter CAC directly
Ketogenic Amino Acids is
any part of carbon skeleton that become sAcetyl CoA. C’s cannot become part of glucose.
Gluconeogenesis is a
metabolic pathway that results in the generation of glucose from non-carbohydrate carb substrates such as pyruvate, lactate, glycerol, glucogenic amino acid, and odd-chain fatty acid.
Gluconegogenesis is only found where?
liver and certain kidney cells.
Where does gluconeogensis begin?
in mitochrondria; returns to cytosol
Typically fatty acids cannot be
converted to glucose, although glycerol can.
Insulin does what 3 things?
Increases in the blood after eating, activates storage enzymes, signals cellular uptake of glucose, fatty acids and amino acids
Glucagon, epinephrine, and cortisol are ____ hormones
Catabolic
Catabolic hormones trigger the breakdown of what 3 things for energy?
Triglycerides, glycogen, and body protein
Looking at inborn errors of metabolism, what is PKU or Phenylketonuria?
Unable to metabolize phenylalanine
Looking at inborn errors of metabolism, what is Galactosemia?
Unable to metabolize galactose
Looking at inborn error of metabolism, what is Glycogen Storage Disease?
Inability to convert glycogen to glucose in liver
Disposal of Excess Amino Acid groups
- Catabolism of AA yields amine group in liver.
- converted to ammonia
- excreted by kidney in the urine with urea cycle
Nitrogen in blood can diagnosis disease:
- Liver Disease: ammonia build up in blood. (liver was damaged)
- Kidney disease- urea build up in blood (liver unable to excrete
Alcohol Metabolism: Alcohol Dehydrogenase (ADH) MAIN PATHWAY!
- mostly in liver with 10-30% in stomach
- uses NAD to convert toxic alcohol into non-toxic metabolite acetaldehyde
- occurs in cytosol of liver cells
- NAD supplies become limited- CAC slows-blocks entry of Acetyl CoA directing it to FA and TAG synthesis- results in accumulation of fat in liver
Alcohol Metabolism:
Microsomal ethanol oxidizing system(MEOS)
- secondary pathway
- when ADH path cannot keep up with toxicity of alochol and acetaldehyde (moderate to excessive alcohol)
- uses energy rather than producing energy
- uses oxygen and NADP to convert alcohol into acetaldehyde
- alternative pathway of alcohol metabolism increases after chronic exposure to alcohol
- happens in microsomes of liver cells
Alcohol poisoning
in excessive intake–1st two paths and enzymes incapable of keeping up
Alcohol Metabolism:
Catalase Pathway
- minor pathway for alcohol oxidation
- breakdown alcohol in the presence of hydrogen peroxide
- occurs in peroxisomes of liver cells
Regulation of Liver
nutrient interconversions and storage
Regulation of ATP concentrations regulate metabolism
High ATP promotes Anabolic reaction
High ADP stimulate Catabolic reactionsvv
Vitamins and Minerals are
coenzymes and enzymes
