oat bio unit 5

i cry tears of gasoline when i have a bad rngdle

mitochondria

Site of aerobic cellular respiration to synthesize ATP. Cells that require more energy (like muscle) have more mitochondria.

mitochondrial DNA

circular, inherited from mother, and independent of regular DNA.

mitochondria layers

• Outer mitochondrial membrane: smooth and encompasses the entire mitochondria.

• Intermembrane space: area between the inner and outer mitochondrial membranes.

• Inner mitochondrial membrane: Folded to increase surface area (folds are called christae).

• Mitochondrial matrix: Space enclosed by the inner mitochondrial membrane.

cellular respiration equation

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy

• Oxidative and Exergonic

substrate level phosphorylation

Enzyme directly transfers a phosphate to ADP to make ATP.

oxidative phosphorylation

Production of ATP using energy from redox reactions in ETC.

glycolysis equation

Glucose + 2 NAD⁺ + 2 ADP → 2 pyruvate + 2 ATP + 2 NADH + 2 H₂O

glycolysis

turns glucose into 2 pyruvates for CAC. It happens in the cytosol and produces ATP via substrate level phosphorylation. It does not need oxygen to occur.

glucose to glucose-6-phosphate

Hexokinase uses one molecule of ATP to convert glucose into glucose 6-phosphate. This gives glucose a negative charge which prevents it from leaving the cell.

Fructose 6-phosphate to Fructose 1,6-biphosphate

Phosphofructokinase uses one ATP to convert fructose 6-phosphate to fructose 1,6-biphosphate. This is an irreversible step that commits the molecule to glycolysis. It also causes a negative feedback loop for ATP production.

pyruvate decarboxylation equation

pyruvate → acetyl CoA + CO₂ + NADH (remember 1 glucose makes 2 pyruvates)

pyruvate decarboxylation

catalyzed by pyruvate dehydrogenase complex (PDC), is an aerobic process, and occurs in the mitochondrial matrix.

CAC

an aerobic process which produces ATP from acetyl CoA via substrate level phosphorylation. It takes place in the mitochondrial matrix.

CAC steps

Acetyl CoA merges with oxaloacetate to form citrate, which then goes through 7 additional steps, which produces oxaloacetate again at the end. The cycle goes twice for each glucose.

Acetyl CoA yield

1 ATP + 3 NADH + 1 FADH₂ + 2 CO₂ (remember 1 glucose = 2 acetyl CoA)

NADH and FADH₂

• Coenzyme nucleotide molecules

• Reduced from NAD⁺ and FAD during CAC

• Electron carriers used in ETC.

ETC

a series of proteins in the inner membrane of the mitochondria that produce 34 ATP

proton motive force and chemiosmosis

• During ETC, protons are pushed against the gradient from the matrix to the intermembrane space (endergonic process coupled with electron transport).

• To balance concentration of H⁺, it moves back across the membrane through ATP synthase, which drives ATP production

ETC steps

• NADH passes an electron to complex I, becoming NAD⁺.

• FADH₂ passes an electron to complex II, becoming FAD.

• Last step: electrons are transferred from complex IV to O₂.

• O₂, electrons, and protons combine to form water.

ATP synthase

turns ADP into ATP via oxidative phosphorylation (hydrogens move through _______________ into the mitochondrial matrix which drives ATP production).

total yield for one glucose

• Glycolysis: 2 ATP + 2 NADH

• Pyruvate decarboxylation: 2 NADH

• CAC: 2 ATP + 6 NADH + 2FADH₂

• ETC: 34 ATP

cellular respiration net ATP yield

• 36.

  • 2 from glycolysis, 2 from CAC, and 34 from ETC

• 2 are used up to move 2 NADH from cytosol to mitochondria.

cellular respiration table

	Glycolysis	Pyruvate Decarboxylation	CAC	ETC
Location	Cytosol	Mito matrix	Mito matrix	Inner mito membrane
(An)aerobic?	Anaerobic	Aerobic	Aerobic	Aerobic
Purpose	Make ATP Pyruvate for CAC	Synthesis of acetyl-CoA	Make elec carriers (NADH and FADH2)	Make ATP

anaerobic respiration

includes glycolysis, CAC, and ETC, but O₂ is not the final electron acceptor.

• Actual final acceptors: SO₄^2-, NO₃^-, S, etc.

anaerobic fermentation

includes glycolysis, but not CAC or ETC. It occurs in the cytoplasm, and allows for the regeneration of NAD⁺. It is a strictly anaerobic process.

• Two types: Alcohol fermentation and lactic acid fermentation.

alcohol fermentation

happens in yeast and some bacteria.

• Step 1: Pyruvate → acetaldehyde and CO₂

• Step 2: Acetaldehyde + NADH → ethanol + NAD⁺.

lactic acid fermentation

happens in human muscle cells, fungi, and bacteria.

• Happens during intense exercise.

• Pyruvate + NADH → lactate + NAD⁺.

• Makes NAD⁺ so it can be used in glycolysis.

• Lactate is transported to liver to be converted back to glucose via Cori cycle.

prokaryotic cellular respiration

• Aerobic yields 38 ATP due to having no membrane bound organelles.

• ETC happens in cell membranes.

alternate energy sources

when glucose isn’t available, cells can use other carbs, lipids, or proteins for energy.

carbohydrate metabolism pathways

• Glycogenesis

• Glycogenolysis

• Gluconeogenesis

• Glycolysis

glycogenesis

making glycogen from glucose to store it for later use; costs 1 ATP per glucose.

glycogenolysis

breaking down stored glycogen into usable glucose.

gluconeogenesis

synthesis of glucose from non-carbohydrates in the liver and kidney.

insulin

released by pancreas when glucose is too high.

• Tells cells to uptake glucose and start making glycogen.

• Promotes glycolysis.

glucagon

released by pancreas when glucose is too low.

• Triggers glycogenolysis.

• Inhibits glycogenesis and glycolysis.

triglyceride breakdown

• Glycerol can be phosphorylated to be converted into a glycolysis intermediate.

• The three fatty acids are broken down via beta oxidation in mitochondria to make ATP.

beta oxidation

• Two carbons are broken off of a fatty acid chain repeatedly to make acetyl CoA for the CAC.

• Also makes 1 NADH and 1 FADH₂.

• Fat yields a lot of ATP, but it takes longer, so the body uses glucose.

• Happens in the mitochondrial matrix.

ketone metabolism

• Ketones are a byproduct of fat breakdown, and are used as a secondary energy source for the brain.

• Ketones are funneled into CAC to make ATP.

proteins as an energy source

least desirable source of energy, only to be used when carbs and fats are unavailable.

• Amino acids are broken down into CAC intermediates.

oxidative deamination

removing an amino group to make other metabolic intermediates.

• The removed amino group becomes ammonia, which is converted to urea

nucleic acids

not used as an energy source.

orbit

you fell in the ball pit