Ch9 - Cellular Respiration

Question 1

What is a calorie?

Answer 1

The amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celcius

Question 2

How much ATP does 1 calorie give?

Answer 2

9000 ATP

Question 3

What is cellular respiration?

Answer 3

process by which energy from glucose/ food compounds is released by being broken down

Question 4

Aerobic vs Anaerobic

Answer 4

Aerobic: using oxygen
Anaerobic: without oxygen

Question 5

What is the equation for Cell Respiration?

Answer 5

C6H12O6 + 6O2 –> 6CO2 + 6H2O (+ energy)

Question 6

What is the pathway for the steps of respiration?

Answer 6

1. Glycolysis
   OXYGEN
2. Krebs Cycle
3. ETC
   WITHOUT OXYGEN
4. Fermentation

Question 7

What is Glycolysis?

Answer 7

Process of breaking down glucose into 2 pyruvates (anaerobic)

Question 8

What are the steps of glycolysis?

Answer 8

• Occurs in cytoplasm
• Uses 2 ATP
  1. Breaks down glucose into 2 PGAL
  2. Phosphates from PGAL are removed to make pyruvate
• 4 ATP are made
• 2 NADH are made

Products:
2 net ATP
2 pyruvate
2 NADH

Question 9

What happens in the preparatory stage?

Answer 9

• CoA (coenzyme A) is added
• CO2 is released
• NADH is formed

Products:
2 Acetyl CoA
2 NADH

Question 10

What is the Krebs Cycle?

Answer 10

AKA Citric Acid Cycle
Process where Acetyl CoA are modified to release energy filled molecules: NADH, FADH2, ATP while releasing CO2

Question 11

What are the steps of the Krebs Cycle?

Answer 11

• Occurs in the mitochondrial matrix

1. Citric Acid Production
   - Acetyl CoA binds to Oxaloacetate (4-carbon) –> Citric Acid (6-carbon)
2. Energy Extraction
   - Citric acid is broken down to a 4-carbon molecule
   - CO2 is released
   - Energy carries (NADH & FADH2) hold released energy

Products of 1 Acetyl CoA
2 CO2
3 NADH
1 FADH2
1 ATP

Question 12

What is the ETC/ where does it happen?

Answer 12

ETC: electron transport chain (inner membrane)
- Uses high-energy electrons from Krebs Cycle to form ATP

Question 13

What are electron carriers?

Answer 13

Electron carriers: move high energy electrons from molecule to molecule

Question 14

What happens at the end of ETC?

Answer 14

enzyme combines electrons from electron chain with hydrogen ions & oxygen → forming water

Question 15

What is fermentation? 2 types of fermentation?

Answer 15

Fermentation: Recycling of electron carriers w/out oxygen
1. Lactic Acid Fermentation
- pyruvic acid (glycolysis) becomes lactic acid
- NADH is oxidized to NAD+ (recycled to glycolysis)

• Lactic acid builds up in muscles during rapid exercise w/out enough oxygen
• Causes burning sensation in muscles

2. Alcoholic Fermentation
   - Allows microorganisms to produce alcohol & CO2
   pyruvate releases CO2 –> acetaldehyde –> ethanol
   - NADH is oxidized to NAD+

Question 16

How many ATP are produced at each stage?

Answer 16

Glycolysis: 2 ATP, 2 NADH = 6 ATP
Preparatory: 2 NADH = 6 ATP
Krebs Cycle: 2 ATP, 6 NADH = 18 ATP, 2 FADH2 = 4 ATP

Total: ~~ 38 ATP

Question 17

How does our body obtain energy?

Answer 17

Body uses stored ATP from muscles for energy

Question 18

What are our sources of ATP?

Answer 18

Stored ATP
Lactic acid Fermentation
Respiration

Question 19

How do we receive short-term energy?

Answer 19

Lactic Acid Fermentation (without Oxygen)
- getting rid of lactic acid requires extra oxygen

Question 20

How do we receive long-term energy?

Answer 20

Cellular respiration
- releases energy slower than fermentation
- uses energy stored in muscles & tissue as carbs
- After carbohydrates, fats are broken down for energy

Question 21

Differences between photosynthesis & cellular respiration

Answer 21

Photosynthesis
- Removes CO2 from atmosphere
- releases Oxygen into atmosphere
- Plants, algae, microorganisms
- function: energy storage
- location: chloroplasts
- Reactants: CO2 & H2O
- Products: Glucose & O

Cellular Respiration
- releases CO2 into atmosphere
- removes oxygen to release energy from food
- all cells
- function: energy release
- location: mitochondria
- reactants: glucose & O
- products: CO2 & H2O

Question 22

What are the parts of mitochondria

Answer 22

1. Outer membrane
2. Inner membrane
   3 inter-membrane space
3. Cristae
4. Matrix