Question

A research group has discovered an organism with cells that contain a previously undescribed organelle. They do some tests on the isolated organelle to see if it is involved in any major metabolic reactions. To do this, they incubate these organelles for a period of time and determine changes in the amount of various substances in the suspending solution. The results follow.

Based on this analysis, which metabolic process do you conclude is taking place in this organelle?



Select one:

a. pyruvate oxidation

b. citric acid cycle

c. glycolysis

d. electron transport chain/oxidative phosphorylation

e. glycolysis and the citric acid cycle

2. A research group has discovered an organism with cells that contain a previously undescribed organelle. They do some tests on the isolated organelle to see if it is involved in any major metabolic reactions. To do this, they incubate these organelles for a period of time and determine changes in the amount of various substances in the suspending solution. The results follow.



Based on this analysis, which metabolic process do you conclude is taking place in this organelle?

Select one:

a. pyruvate oxidation

b. citric acid cycle

c. glycolysis

d. electron transport chain/oxidative phosphorylation

e. glycolysis and the citric acid cycle

Answer 1

The suitable option will be - B

Citric acid cycle

Explanation:

The results were -

Glucose: None

CO2: Increase

O2: None

ATP: Increase

NADH: Increase

• We know that the Citric acid cycle is also known as the TCA cycle (tricarboxylic acid cycle) or the Krebs cycle. This cycle occurs in Mitochondria in case of eukaryotes. In this cycle acetyl-CoA is oxidized which comes from carbohydrates, proteins and fats and energy is released in the form of ATP.

• water is also used in this process. NAD+ gets reduced to NADPH. In this system carbon dioxide is produced as a waste byproduct. ATP is produced as the main product. ATP is also used as a source of energy.