CELLULAR RESPIRATION Biology I INTRODUCTION TO CELLULAR RESPIRATION

CELLULAR RESPIRATION Biology I

INTRODUCTION TO CELLULAR RESPIRATION Both photosynthesis and cellular respiration provide energy for life. Photosynthesis uses solar energy to produce glucose and O 2 from CO 2 and H 2 O 6 CO 2 + 6 H 20 + ATP C 6 H 12 O 6 + 6 O 2 Occurs in Chloroplasts

Cellular respiration makes ATP and consumes O 2 during the oxidation of glucose to CO 2 and H 2 O C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O + ATP Occurs in mitochondria So what is the relationship between photosynthesis and cellular respiration?

Sunlight energy ECOSYSTEM Photosynthesis in chloroplasts Glucose CO 2 + + H 2 O O 2 Cellular respiration in mitochondria ATP (for cellular work) Heat energy

Breathing (respiration) provides for the exchange of O 2 and CO 2 between an organism and its environment. Happens in the lungs

Cellular respiration breaks down glucose molecules and banks their energy in ATP. Occurs in the mitochondrion of cells. C 6 H 12 O 6 Glucose + 6 O 2 Oxygen gas 6 CO 2 Carbon dioxide + 6 H 2 O Water + ATPs Energy

What is the relationship between respiration and cellular respiration? O 2 Breathing CO 2 Lungs CO 2 Bloodstream O 2 Muscle cells carrying out Cellular Respiration Glucose + O 2 CO 2 + H 2 O + ATP

The human body uses energy from ATP for all its activities. ATP powers almost all cellular and body activities 75% used for life-sustaining activities (involuntary) The other 25% of this is used for. . .

Both plant and animal cells carry out the final stages of cellular respiration in their mitochondria.

Glucose is a main energy source used by all cells. Cells don’t “burn” glucose. Instead, they gradually release the energy from glucose and other food compounds. • This process begins with a pathway called glycolysis. • Glycolysis releases a small amount of energy

First Phase – Glycolysis • Occurs in the cytoplasm • Anaerobic – no oxygen needed • Breaks down glucose into simpler substances • Produces a net gain of 2 ATP molecules

Second Phase – Krebs Cycle • Occurs in the mitochondria • Aerobic – oxygen required • Begins with products from glycolysis

Each “turn” of the Krebs Cycle yields: Totals: 2 ATP molecules 4 CO 2 molecules

Third Phase – Electron Transport Chain Uses the energy stored in the products of the Krebs Cycle make 32 ATP molecules. Water is produced as a byproduct