Muscle cells can still use aerobic breathing to break down food even if they don’t have enough oxygen. This lets them keep making energy. Human muscle cells do not create alcohol like yeast, but lactic acid is a major byproduct of the process.
Let’s explore the full answer to the question:
“In muscle cells, fermentation produces ___.”
A) Alcohol
B) Lactic acid
C) Carbon dioxide
D) Glucose
Correct Answer: B) Lactic acid
Explanation
During conditions of lowered oxygen in muscle cells, lactic acid is generated by fermentation. With this anaerobic pathway, NADH can be recycled into NAD+ so that other glycolysis steps can continue providing ATP energy to the body within a short time. Whilst it produces much less ATP than aerobic respiration, it is vital when there is strenuous exercise, when the amount of oxygen delivered cannot keep pace with its demands.
Examples include
- Sprint or high-intensity interval workouts, as the oxygen usage surpasses the provision
- Intensive moving or tiny spurts of power
- Strong movement exercises in breath-holding
What is Lactic Acid Fermentation?
Lactic acid fermentation. There is a conversion of pyruvate, which is a glycolytic end product, to lactic acid by lactate dehydrogenase. It occurs in the cytoplasm of muscle cells, enabling the continuance of the production of ATP in the presence of no oxygen.
Key features:
- Anaerobic- does not need oxygen
- 2 ATP per mole of glucose
- Reforms NAD+ to maintain the operation of glycolysis
- May cause temporary muscle pains or weakness
Scientific Context
Lactic acidosis fermentation is important in short term high-intensity activity. Upon restoration of normal oxygen levels, lactic acid is passed to the liver, where it is broken down once more into glucose by the Cori cycle.
Key Elements
- Trigger: Low oxygen levels
- Main product: Lactic acid
- Role: To keep up the ATP in anaerobic environments
- Outcome: Potential temporary pain (or impeded muscular productivity)
FAQs
Q1: Why do muscles produce lactic acid?
In case the product of glycolysis is to generate ATP in the absence of oxygen by recreating NAD+.
Q2: Is lactic acid harmful?
Not at normal levels — it is cleared by the liver and recycled into glucose.
Q3: Does lactic acid cause muscle cramps?
Recent researches indicate that cramps have less to do with lactic acid accumulation and more to do with nerve fatigue.
Q4: Do other organisms use lactic acid fermentation?
Yes, it is used in the production of some foods by bacteria; yoghurt and kimchi are examples.
