2.8 - Anaerobic Respiration

Question 1

Which stage(s) in cellular respiration does not reqire oxygen to function?

Answer 1

Glycolysis

Question 2

Which stage(s) in cellular respiration does reqire oxygen to function?

Answer 2

Pyruvate oxidation, krebs cycle, and electron transport chain

Question 3

How is lactic acid/ lactate made?

Answer 3

Pyruvate regains the hydrogens & the electrons it lost to NADH. This turns it into lactic acid

Question 4

What happens in Lactic Acid Fermination?

no oxygen present

Answer 4

• pyruvate + NADH –> lactate + NAD+
• NAD+ must be regenerated for glycolysis to occur
• turns glycolysis into a cycle of reusing NAD+ to make ATP (when no O2 is present)
• when O2 is replenished, the lactate goes into the liver to be turned back into pyruvate using even more oxygen

no oxygen present

Question 5

Where does lactic acid fermination occur?

Answer 5

It occurs in animals, in small localized areas.
Ex) runner running marathon

Question 6

What molecule and how does ethanol fermentaion begin?

Answer 6

Pyruvate is decarboxylated (looses a carbon) to form acetaldhyde [a-see-tal-hyde]. This causes it to regain the hydrogen & electron it lost to NADH to become ethanol

Question 7

Ethanol fermentation creates what common dangerous substance?

Answer 7

All alcoholic drinks

Question 8

Give a non-alcoholic example of enthanol fermentation?

Answer 8

Bread
- the carbohydrates sealed in an anaerobic environment with yeast causes the dough to rise
- the CO2 causes bread to rise due to it’s air bubbles