cellular respiration

Question 1

Respiration

Answer 1

One of the 8 life functions

Physical - organism inhales O2 into the lungs & exhales CO2

Cellular - O2 is used by the mitochondria to completely break down glucose, releasing ATP

Question 2

Breakdown of glucose

Answer 2

Glucose is broken down in a series of steps that releases energy in small amounts

If all of the energy was released at once, the cell would die

Glucose is oxidized, electrons & hydrogen atoms are removed

Question 3

Cellular Energy

Answer 3

ADP - Adenosine Diphosphate

ATP - Adenosine Triphosphate
• stores & transfers the energy released from the breakdown of glucose
• releases the energy it carries by breaking the outer bond attaching the phosphates

Question 4

Aerobic Respiration

Answer 4

Stage 1 : Glycolysis (does not require O2)
• reaction - glucose + 2 atp > 2 G3P > 2 pyruvic acid + 4 atp
• net overall gain of atp = 2

Stage 2 : Aerobic (requires O2)
•reaction - 2 pyruvic acid > 6 CO2 + 6H2O + 34 ATP
• net overall gain of atp = 34

Question 5

Aerobic Phase

Answer 5

• pyruvic acid breakdown
  -krebs cycle (2 atp)
  -electron transport chain (32 atp)

Question 6

Krebs (citric acid) cycle

Answer 6

Following is produced
• 4 CO2 molecules
• 2 ATP molecules
• NADH & FADH2 hold most of the energy previously stored in glucose

Question 7

ETC & chemiosmosis

Answer 7

protons (H+) are pumped out of the inner chamber by proton pumps by the process of active transport
•protons that build up outside rush back into the inner chamber by facilitated diffusion through a protein channel known as ATP synthase, generating ATP

• end of ETC forms water
-requires oxygen bc otherwise ETC would become clogged with electrons
-oxygen is referred to as the final electron acceptor

Question 8

Anaerobic Reaction

Answer 8

• Breakdown of glucose when O2 is not present
• Carried out by yeast, bacterial, and muscle cells
• Occurs in the cytoplasm of a cell
• Less efficient bc it only partially breaks down glucose, producing less ATP (fermentation)

Step 1 : Glycolysis
- splitting of glucose into 2 molecules of pyruvate
-produces a net gain of 2 ATP molecules

Step 2: Fermentation
-electron transport chain does not run
- in yeast, bacterial, and muscle cells

Overall reaction : C6H12O6 + 2 ATP > 2 pyruvic acid + 4 ATP > ethyl alcohol + CO2 and lactic acid

Question 9

Lactic acid

Answer 9

Makes muscles feel sore when overworked and depleted of oxygen