SAS 7&8 Quiz

What is the primary function of the electron transport chain?

• To produce ATP

• To convert glucose to pyruvate

• To synthesize fatty acids

• To break down amino acids

Answer explanation

The primary function of the electron transport chain is to produce ATP. It does this by transferring electrons through a series of proteins, which helps create a proton gradient that drives ATP synthesis.

The "fuel" for the Citric Acid Cycle is

• Acetyl CoA

• Citric Acid

• Citrate Ion

• Oxaloacetate ion

Answer explanation

The 'fuel' for the Citric Acid Cycle is Acetyl CoA, which is derived from carbohydrates, fats, and proteins. It combines with oxaloacetate to form citrate, initiating the cycle.

Which of the following is defined as the creation of new glucose from molecules that are not carbohydrates, such as proteins and lipids?

• Glycogenesis

• Glycogenolysis

• Gluconeogenesis

• Glycolysis

Answer explanation

Gluconeogenesis is the process of creating new glucose from non-carbohydrate sources like proteins and lipids. Glycogenesis, glycogenolysis, and glycolysis refer to different metabolic processes involving carbohydrates.

Which hormone is primarily responsible for lowering blood glucose levels?

• Insulin

• Glucagon

• Cortisol

• Adrenaline

Answer explanation

Insulin is the hormone that lowers blood glucose levels by facilitating the uptake of glucose into cells, thus reducing the concentration of glucose in the bloodstream. Glucagon, cortisol, and adrenaline have the opposite effect.

Initial Site for digestion of carbohydrates

• Stomach

• Small intestine

• Villi

• Mouth

Answer explanation

The mouth is the initial site for carbohydrate digestion, where enzymes in saliva begin breaking down starches into simpler sugars. The stomach and small intestine continue digestion, but the process starts in the mouth.

Which of the following processes breaks down glycogen into glucose?

• Glycogenesis

• Glycogenolysis

• Gluconeogenesis

• Glycolysis

Answer explanation

Glycogenolysis is the process that breaks down glycogen into glucose, providing energy when needed. In contrast, glycogenesis builds glycogen, gluconeogenesis creates glucose from non-carbohydrates, and glycolysis breaks down glucose.

At which step in the electron transport chain does O2 participate?

• first step

• second step

• third step

• fourth step

Answer explanation

O2 participates in the fourth step of the electron transport chain, where it acts as the final electron acceptor, forming water. This step is crucial for maintaining the flow of electrons and the production of ATP.

What is the end product of glycolysis?

• Glucose

• Pyruvate

• Lactate

• Acetyl CoA

Answer explanation

The end product of glycolysis is pyruvate, which is formed from glucose through a series of enzymatic reactions. Lactate and Acetyl CoA are products of further metabolism, not glycolysis itself.

If you eat carbohydrate-rich meal your body will move the excess glucose out of your blood to store it as _________, through a process known as __________.

• Glycogen, Glycogenolysis

• Glycogen, Glycogenesis

• Triglyceride, Glycogenolysis

• Triglyceride, Glycogenesis

Answer explanation

When you consume a carbohydrate-rich meal, excess glucose is converted and stored as glycogen through the process of glycogenesis, not glycogenolysis, which is the breakdown of glycogen into glucose.

TRUE OR FALSE: The Krebs cycle occurs in the cytoplasm of the cell.

• TRUE

• FALSE

Answer explanation

FALSE: The Krebs cycle, also known as the citric acid cycle, occurs in the mitochondria of the cell, not the cytoplasm. This is where it plays a crucial role in cellular respiration.