Cellular Respiration Cellular Respiration Overall word equation reactants

Cellular Respiration

Cellular Respiration Overall word equation: reactants glucose + oxygen Overall chemical equation: C 6 H 12 O 6 + 6 O 2 end product waste products carbon dioxide + water + energy • released into air • exhaled 6 CO 2 + 6 H 2 O + 36 ATP energy used for life functions • movement (heart & lungs) • nerve & brain activity • synthesis & repair of body parts

Where does cellular respiration occur? Cellular respiration can occur in two places: • in the cytoplasm (when no oxygen is present), doesn’t create much energy • in the mitochondrion (when oxygen is present), much more efficient in creating energy

LACTIC ACID FERMENTATION (anaerobic) Overall word equation: glucose used by: 1. animal muscle cells: lactic acid + 2 ATP • 5% of available energy in glucose • not very efficient • lactic acid build up in muscles causes muscle fatigue • under conditions of strenuous activity when muscles can’t get enough O 2 • when O 2 present lactic acid sent to mitochondria for aerobic cellular respiration 2. lactic acid bacteria: • used to make yogurt & other dairy products • lactic acid gives sour taste

ALCOHOLIC FERMENTATION (anaerobic) Overall word equation: glucose alcohol + carbon dioxide + 2 ATP • 5% of available energy in glucose • not very efficient used by: yeast cells: under anaerobic conditions yeast break down glucose to alcohol & CO 2 commercial uses 1. beer & wine 1. make bread rise 2. bio-fuel

ADP – ATP CYCLE the released energy must be trapped, otherwise it would dissipate, if not used immediately all organisms use the same energy trapping compound called ATP (adenosine triphosphate) high energy bonds • a phosphate bond is broken • energy released is used by body for life functions = lots of chemical energy ATP ADP • energy released by cellular respiration is used to add a phosphate to ADP • ATP is reformed • energy is trapped in 3 rd phosphate bond

ADP – ATP CYCLE Overall word equation: • during cellular respiration ADP + energy A ~P~P + energy ATP A ~P~P~P Overall word equation: • when body needs energy to live ATP A ~P~P~P ADP + energy A ~P~P + energy

Homework Page 82 # 2, 3, 7