Cellular Respiration & Fermentation: Ch. 7.4 - 7.6

Objectives

1. Importance of mitochondrion’s structure

2. Inputs & outputs of cellular respiration

3. Anaerobic vs. Aerobic conditions

4. Importance of fermentation; when/where it occurs

Transfer of Energy

We Need Energy!

• All living things need energy.

• Forms of Energy: 1. Food = chemical energy

2. ATP = cell energy

• Cells make energy in 2 ways:• Photosynthesis: takes place

in chloroplasts

• Cellular Respiration: takes place in mitochondria

Mitochondrion

• Ideal place to make energy. Why?

• Structure is key. What do you notice?

• Many folds --> large surface area– allows for a lot of ATP

production

Inputs vs. Outputs in Cellular Respiration

Inputs

Outputs

Cellular Respiration

C6H12O6 + 6O2 ---> 6CO2 + 6H2O + ATP (Energy!)

Glucose + Oxygen ---> Carbon Dioxide + Water + ATP (38)

•Is cellular respiration aerobic or anaerobic?

Cellular respiration is aerobic:

requires oxygen

Aerobic. Why?

The End Product

• The result of cellular respiration is the generation of ATP

• 1 molecule glucose --> 38 molecules of ATP!

• This is what keeps us alive!

38ATP

Cellular Respiration: the relationship to breathing

No Oxygen?

• Do all cells need oxygen all of the time?• Anaerobic environment:

– w/o oxygen

• What are some examples? • Sprinting

Fermentation

• Fermentation:– Makes ATP w/o using

oxygen

• Sprinting– Lungs and blood can’t

supply oxygen fast enough to meet muscles needs

– Body resorts to fermentation for short bursts of activity

• What happens?

Feel the Burn!• Fermentation in a muscle cell produces a waste product called lactic acid --> burns!

• Buildup of lactic acid causes soreness during and after exercise

• Body eventually converts lactic acid back to pyruvic acid

More Fermentation

• Yeast (microscopic fungus) cells:

• In anaerobic environment it produces alcohol and CO2 --> beer

• Makes bread rise• Sharp flavor of cheese

– Due to lactic acid

Fermentation

performed by

Muscle cells Bacterial fungi yeast

Lactic acid Ethyl alcohol CO2

Sore muscles Sour/sharp taste bubbles

produces produces & releases

that in the body causes

that in food causes in bread causes