Respiration

The end product of glycolysis is used to make (a)  

• Acetyl CoA
• Glucose
• Oxygen
• Water

Answer explanation

The end product of glycolysis is pyruvate, which is then converted into Acetyl CoA. This conversion is crucial for entering the citric acid cycle, making Acetyl CoA the correct answer.

What is regenerated at the end of the Krebs cycle?

• Starting material

• Oxygen

• Glucose

• Water

Answer explanation

At the end of the Krebs cycle, the starting material, oxaloacetate, is regenerated. This allows the cycle to continue, as it combines with acetyl-CoA to form citrate, initiating the cycle again.

Match the following coenzymes with their roles in cellular processes.

• Important in cellular respiration

• DNA

• Involved in protein synthesis

• NAD

• Primary energy carrier in cells

• RNA

• Genetic material in cells

• ATP

Answer explanation

NAD (Nicotinamide adenine dinucleotide) is a crucial coenzyme in cellular respiration, acting as an electron carrier in metabolic reactions, particularly in the Krebs cycle and oxidative phosphorylation.

Anabolic reactions include: (a)  

• Active transport using the sodium-p
• Synthesis of protein from amino aci
• Cellular movement of chromosomes vi
• Only occurs in mammals and birds.

Answer explanation

Anabolic reactions involve building complex molecules. The synthesis of protein from amino acids is a classic example of an anabolic process, while the other options describe different cellular functions or are incorrect.

What is the energy currency of cells that carbohydrates can be broken down into?

• DNA

• RNA

• ATP

• ADP

Answer explanation

The energy currency of cells is ATP (adenosine triphosphate). Carbohydrates are broken down during cellular respiration to produce ATP, which provides energy for various cellular processes.

What is the chemical formula for glucose in the cellular respiration equation?

• C6H12O6

• C5H10O5

• C6H14O6

• C7H12O7

Answer explanation

The chemical formula for glucose is C6H12O6, which is essential in cellular respiration. The other options do not represent glucose, making C6H12O6 the correct choice.

In the process of cellular respiration, (a)   is produced along with water and carbon dioxide.

• Oxygen
• Glucose
• Energy (ATP)
• Nitrogen

Answer explanation

In cellular respiration, glucose is broken down to produce energy in the form of ATP, along with water and carbon dioxide. Therefore, the correct answer is Energy (ATP).

What is the role of ATP in cells?

• It stores energy for cellular activities

• It acts as a waste product

• It is used to build proteins

• It is a type of sugar.

Answer explanation

ATP, or adenosine triphosphate, is the primary energy carrier in cells. It stores energy that is released during cellular activities, making it essential for processes like muscle contraction and biochemical reactions.

(a)   is released when carbohydrates are broken down in respiration.

• Nitrogen
• ATP
• Glucose
• Oxygen

Answer explanation

When carbohydrates are broken down during respiration, they are converted into energy, which is stored as ATP (adenosine triphosphate). This process does not release nitrogen, glucose, or oxygen directly.

What is the significance of mitochondrial DNA?

• It encodes proteins for the cell membrane

• It is involved in cellular respiration

• It is inherited maternally and encodes essential proteins for mitochondrial function

• It is used for photosynthesis

Answer explanation

Mitochondrial DNA is significant because it is inherited maternally and encodes essential proteins for mitochondrial function, which are crucial for energy production in cells.