BIOL Exam 2C - Cellular Resipiration

Zanzot Auburn, BIOL-1020 Principle of Biology I

sunlight

how energy enters ecosystems

heat

how energy leaves ecosystems

photosynthesis

generates O₂ and sugar (org. molecules)

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ATP + heat

formula for cellular respiration

glucose is oxidized

O₂ is reduced

non-reversible

cellular respiration is a ___ process

redox reactions

chemical reactions that transfer electrons between reactants

oxidation (OIL)

a substance loses e- (is oxidized)

reduction (RIG)

a substance gains e-

1. Glycolysis (cytoplasm)

2. Pyruvate Oxidation

3. Citric Acid Cycle

4. Oxidative Phosphorylation

steps in aerobic respiration

NAD+ , FAD

coenzyme, oxidizing agent (e- carrier) during cell respiration

substrate-level phosphorylation

directly takes phosphate group from the substrate, adds it to ADP, makes ATP

makes 10% of ATP

oxidative phosphorylation

uses an e- transport chain and proton gradient for ATP synthesis

powered by redox reactions

makes 90% of ATP

glycolysis

start: glucose

finish: H₂O, ATP, NADH, 2 Pyruvate

where: cytoplasm (euk)

glycolysis

breaks down glucose into 2 pyruvate

energy investment and payoff phase

occurs in cytoplasm

glycolysis

universal cell trait

O₂ independent

PER TURN

• 1 ATP

• 3 NADH

• 2 CO₂

• 1 FADH₂

citric acid cycle ending products

bc glucose molecule splits into 2 CoA molecules , the cycle must turn twice to finish

why citric acid cycle makes products per turn

where: mitochondrial matrix (euk)

oxidative phosphorylation

e- transfer in e- transport chain causes proteins to pump H+ from the mitochondrial matrix to the inter-membrane space

oxidative phosphorylation

where: inner mitochondria (euk)

*only process that consumes O₂ to make H₂O

water, CO₂

cellular respiration makes ___, Glucose makes ___

ATP synthase

enzyme making ATP, produces significantly more than substrate-level phosphorylation

drive ATP synthase by chemiosmosis

protons fx in e^- transport chain

fermentation

uses substrate-level phosphorylation instead of an e- transport chain

keeps glycolysis functioning by receiving e- from NADH

**DOES NOT MAKE ATP DIRECTLY

anaerobic respiration

uses an e- transport chain with a final e- acceptor other than O₂

NAD+

moves e^- from glucose to e^- transport chain

in glycolysis, pyruvate oxidation, & kreb cycle

in fermentation and anaerobic respiration

ethanol fermentation

two steps: pyruvate loses CO₂ to become acetaldehyde, is then reduced to ethanol, makes NAD+

lactic acid fermentation

one step: pyruvate is directly reduced by NADH (to make NAD+)

ATP, keeps glycolysis going to make ATP

O₂ directly makes ___ while fermentation _____

biosynthesis

anabolic pathways

body uses smal molecules to build other comlex substances

catabolic pathways funnel e- from many org. molecules

(glycolysis & acetyl CoA synthesis)

how non-glucose molecules can be used to produce ATP in cellular respiration

glycolysis → pyruvate oxidation → kreb cycle → oxidative phosphorylation

understand the cellular respiration process

• acetyl CoA, 3NAD+, FAD

• → 2 CO₂, 3NADH, FADH₂, ATP

citric acid cycle (start/end products)

energy investment → payoff

products: 4 ATP, 2 NADH, 2 pyruvate, 2H₂O

understand the glycolysis process (& products)

• start: pyruvate

• → acetyl CoA, CO₂ , NADH

understand pyruvate oxidation (start/end products)

H⁺ (protons) are pumped out of matrix and into intermembrane soace

e- transport and chemiosmosis

understand the oxidative phosphorylation

oxaloacetate to form citrate

acetyl CoA joins ___ to form ___

something other than O₂ or pyruvate

anaerobic respiration uses _____

• Citrate

• Isocitrate

• a~Ketoglutarate

• Succinyl CoA

• Succinate

• Fumerate

• Malate

• Oxaloacetate

Can I Keep Some Sugar For My Oatmeal