bio ch 7

cellular respiration

catalysis (breakdown) of glucose to produce atp and organic intermediates used in synthesis of other organic molecules needed, total of 38 atp

glycolysis

oldest metabolic pathway, universal, takes place in cytoplasm

aerobic respiration

krebs cycle/citric acid cycle, ETC, chemiosmosis, takes place in mitochondria

C6H12O6+6O2—>6CO2+6H2O+energy

equation for cellular respiration

anaerobic

fermentation

glycolysis

first step of aerobic and anaerobic, does not require O2

aerobic respiration

3 additional steps, second needs O2 as electron receptor of ETC, krebs cycle, etc, chemiosmosis

krebs cycle

takes place in mitochondrial matrix

ETC

takes place in inner membrane of mitochondria

chemiosmosis

takes place across inner membrane of mitochondria

anaerobic fermentation

one additional step after glycolysis, regenerates oxidizing agent (NAD+) to allow glycolysis to operate in absence of O2

catabolic and redox

both fermentation and cellular respiration

2 atp

energy per glucose in anaerobic

36 atp

energy produced per glucose by aerobic

glycolysis

10 step metabolic pathway catalyzed by enzymes that breaks down one glucose to two molecules of pyruvate, bonds of glucose rearranged, NAD+ reduced to NADH (electron carrier), free energy released as ATP (comes from ADP and Pi), pyruvic acid is transported from cytoplasm to mitochondria for oxidation

shuttle step

conversion of pyruvic acid to acetyl coa occurs in matrix of mitochondria, CoA added, pyruvate oxidized, producing NADH, 3 carbon pyruvate converted to 2 carbon acetyl coa release co2

krebs cycle/ citric acid cycle

series of reactions that continually regenerates oxaloacetic acid

1. produces majority of NADH, FADH2 and CO2

2. NADH and FADH2 carry electrons extracted during cycle reactions and carries to ETC

3. ATP is synthesized from ADP and Pi via phosphorylation, coenzymes capture electrons during cycle

4. oxaloacetic acid is added to acetyl coa to make citrate

ETC

carried out by electron carriers that undergo a series of redox reactions as electrons are passed from one carrier to another

1. occurs in mitochondria

2. NADH and FADH2 deliver electrons and pass them to series of electron acceptors as acceptors move toward final acceptor O2

3. passage of electrons is accompanied by proton gradient

4. no direct ATP is made, must be coupled to oxidative phosphorylation via chemiosmosis

pyruvic acid and NADH

can be processed anaerobically in cytoplasm

NAD+

second step of fermentation produces _, required to keep glycolysis running and produce ATP

lactic acid

produced in muscles to supply atp when oxygen demands cannot be met

alcohol fermentation

glycolysis and additional steps to produce NAD+, ethanol, co2 (yeast)