Unit 1 Lesson 12: Fermentation

What are the three main sources of ATP available for human muscle cells?

-ATP already in muscles, ATP made from lactic acid fermentation, ATP produced by cellular respiration

How are the two types of fermentation different and similar?

-Both forms provide energy to the cell in the absence of oxygen, and both produce NAD. They are different because alcoholic fermentation produces alcohol and CO2 and lactic acid fermentation produces lactic acid

What causes humans to become lactic acid fermenters?

-Brief periods without oxygen will cause many cells of the human body to produce ATP by lactic acid fermentation

Lactic acid fermentation

-Converts pyruvic acid to lactic acid -Pyruvic acid + NADH ----> lactic acid + NAD+ -Bacteria that produce lactic acid as a waste product are important to industry: cheese, yogurt -Best human cells for lactic acid fermentation are muscle cells

Lactic acid vs Alcoholic fermentation

-In both types, pyruvate reacts with NADH to form waste products that leave the cell -In lactic acid fermentation, waste product is lactic acid -In alcoholic fermentation, waste products are ethanol and carbon dioxide

Fermentation

-In the absence of oxygen, fermentation releases energy from food molecules by producing ATP -During fermentation, cells convert NADH into NAD+ by passing high-energy electrons back to pyruvic acid -It is an anaerobic process that occurs in the cytoplasm

For short, quick bursts of energy, the body uses ATP already stored in muscles as well as ATP made by _____

-Lactic acid fermentation

What are the two types of fermentation?

-Lactic acid fermentation and alcoholic fermentation

Why does a sprinter have an oxygen debt to repay after the race is over?

-Lactic acid fermentation produces lactic acid as a byproduct. The only way to remove lactic acid is in a chemical pathway that requires extra oxygen

Alcoholic fermentation

-Produces ethyl alcohol and CO2 -Pyruvic acid + NADH ----> Alcohol + CO2 + NAD+

For exercises longer than 90 seconds, _____ is the only way to continue generating a supply of ATP

-cellular respiration

What cells are involved in each type of fermentation?

-lactic acid fermentation occurs in muscle cells when oxygen levels are depleted -Alcoholic fermentation occurs in yeast cells