Glycolysis

Which is a product of glycolysis?

• 2 molecules of pyruvic acid

• 1 molecule of glucose

• NAD+

• oxygen

Answer explanation

Glycolysis breaks down one molecule of glucose into two molecules of pyruvic acid, making pyruvic acid a direct product of this metabolic pathway. The other options are not products of glycolysis.

Glycolysis is the second stage of cellular respiration.

• True

• False

Answer explanation

Glycolysis is actually the first stage of cellular respiration, where glucose is broken down into pyruvate. The second stage is the Krebs cycle. Therefore, the statement is false.

Glycolysis requires oxygen

• True

• False

Answer explanation

Glycolysis is an anaerobic process, meaning it does not require oxygen to occur. It can take place in both aerobic and anaerobic conditions, which makes the correct answer 'False'.

After the NAD+ receives electrons, what does it change to?

• ATP

• NADH

• ADP

Answer explanation

After NAD+ receives electrons, it is reduced to NADH. This process is crucial in cellular respiration, where NADH acts as an electron carrier, facilitating energy production.

During glycolysis, glucose is broken down into how many molecules of pyruvic acid?

• 2

• 3

• 4

• 1

Answer explanation

During glycolysis, one molecule of glucose is converted into two molecules of pyruvic acid. This process involves a series of enzymatic reactions that ultimately split glucose, confirming that the correct answer is 2.

Glycolysis has a net gain of how many ATP molecules?

• 2

• 4

• 6

Answer explanation

Glycolysis produces 4 ATP molecules but consumes 2 ATP, resulting in a net gain of 2 ATP molecules. Therefore, the correct answer is 2.

How many ATP molecules are required to start glycolysis?

• Four

• Three

• Two

• One

Answer explanation

Glycolysis requires an initial investment of 2 ATP molecules to phosphorylate glucose and its intermediates, facilitating the breakdown of glucose into pyruvate. Thus, the correct answer is two.

Where does glycolysis take place in cells?

• Cytoplasm

• Mitochondrion

• Endoplasmic Reticulum

• Ribosomes

Answer explanation

Glycolysis occurs in the cytoplasm of cells, where glucose is broken down to produce energy. This process does not take place in the mitochondrion, endoplasmic reticulum, or ribosomes.

Which is not part of the net products of Glycolysis?

• 2 ATP

• 2 NADH

• 2 Pyruvate

• 2 CO₂

Answer explanation

Glycolysis produces 2 ATP, 2 NADH, and 2 pyruvate. It does not produce 2 CO2; that occurs in the citric acid cycle. Therefore, 2 CO2 is the correct answer as it is not part of the net products of glycolysis.

Glycolysis occurs during aerobic or anaerobic conditions.

• True

• False

Answer explanation

Glycolysis is a metabolic pathway that breaks down glucose to produce energy. It occurs in both aerobic (with oxygen) and anaerobic (without oxygen) conditions, making the statement true.