W13 Lipids

What are the primary carbon substrates for fatty acid synthesis derived from?

• Proteins

• Dietary carbohydrates (in the form of glucose)

• Fats

• Vitamins

Where are dietary fats digested?

• Stomach

• Small intestine

• Large intestine

• Liver

What are triglycerides broken down into during digestion?

• Monoglycerides and free fatty acids

• Amino acids and glucose

• Nucleotides

• Cholesterol

What does lipolysis refer to?

• The synthesis of triglycerides

• The breakdown of triglycerides into glycerol and fatty acids

• The oxidation of fatty acids

• The synthesis of cholesterol

Which of the following is NOT synthesized from acetyl-CoA?

• Fatty acids

• Triglycerides

• Amino acids

• Steroid hormones

Why is acetyl-CoA considered crucial in lipid metabolism?

• It only participates in fatty acid synthesis

• It can enter the Krebs cycle to generate ATP, be used for ketogenesis, or lipogenesis

• It is only involved in cholesterol synthesis

• It has no relation to lipid metabolism

After digestion, how are triglycerides transported to the liver or adipose tissue?

• They are transported as free fatty acids

• They are re-synthesized and transported via chylomicrons

• They are converted into amino acids

• They are directly absorbed by the liver

When there is excess glucose intake, what is the primary fate of acetyl-CoA?

• It enters the Krebs cycle to produce ATP

• It is used for fatty acid synthesis or lipogenesis

• It is excreted from the body

• It is stored as glycogen

What happens during prolonged fasting regarding blood sugar and liver glycogen?

• Blood sugar drops after 4 - 6 hours, and liver glycogen is used after 10 - 12 hours

• Blood sugar remains stable, and liver glycogen increases

• Blood sugar spikes, and liver glycogen is depleted immediately

• There is no change in blood sugar or liver glycogen

What is the role of ketone bodies during extended fasting?

• They increase the need for glucose

• They help prevent the degradation of essential proteins by reducing the need for gluconeogenesis

• They inhibit fat oxidation

• They increase protein synthesis