Cellular Respiration Cellular RespirationConverting Chemical Energy from

Carbohydrates into Chemical Energy of ATP

Converting Chemical Energy from Carbohydrates into Chemical Energy of

ATP

Cellular Respiration (Aerobic ) Cellular Respiration (Aerobic )

• How do cells transform matter and energy?

• What are the major inputs and outputs of cell respiration?

• What is the relationship between cell respiration and study photosynthesis?

Cellular Respiration and PhotosynthesisCellular Respiration and Photosynthesis• These are

‘opposite’ processes

• The products of photosynthesis are the reactants of respiration and vice versa.

• Energy stored through photosynthesis is released through cellular respiration

Cellular Respiration and PhotosynthesisCellular Respiration and Photosynthesis• Photosynthesis

stores small packets of energy in a larger packet.

Like turning in one hundred $1 bills to get a $100 bill

• Cell Respiration takes a lot of energy and breaks it into smaller packets.

Like turning in a $100 bill and getting five $20 bills.

In the mitochondria of living things, oxygen helps the break- down of sugars (glucose) to release energy useable by the cell (ATP)

Cellular Respiration Overview Cellular Respiration Overview

Products and Reactants(1) C6H12O6 + (6) O2 (6) CO2 +

(6) H2O + ATP

GlucoseGlycolysis

Pyruvic acid

Krebs Cycle

Electron Transport

Chain

Mitochondria

CO2 H2O

O2

2 36

H+

• Glycolysis is the anaerobic process of breaking down glucose to generate ATP

• Krebs Cycle and Electron Transport require oxygen to further break down carbon molecules to generate ATP

Cellular Respiration Overview Cellular Respiration Overview

Glycolysis

• Glucose (6 carbon sugar) breaks down into pyruvate (3 carbon molecules ) and ATP (energy)

• Similar to reversing the final stage of photosynthesis when two 3-carbon sugars were used to make glucose

Krebs Cycle

• Pyruvate (3 carbon) breaks down into carbon dioxide (1 carbon) and electrons are used to generate ATP (energy)

• Similar - in reverse - to the Calvin cycle in photosynthesis

Electron Transport ChainElectron Transport Chain

• Electrons generated during glycolysis and Kreb’s cycle are used to generate ATP

• At the end they come together with oxygen to form water

• Again, similar, but in reverse of the electron transport chain in the light dependent reactions of photosynthesis

• 36 ATP units are released from one glucose unit

• A unit of glucose molecules contains 686 kcal of stored energy. A unit of ATP stores 7.5 kcal.

• How efficient is the transformation from energy stored in glucose to energy released as ATP?

Energy Transformed - Cell Respiration

Energy Transformed - Cell Respiration