Creatine Kinase/Phosphagen System

The video tutorial explains the role of creatine as a common nutritional supplement, its biochemical basis, and how it enhances exercise performance. Creatine is derived from amino acids and is not an essential nutrient. The enzyme creatine kinase facilitates a reversible reaction that transfers phosphate from ATP to creatine, forming creatine phosphate. This process helps maintain ATP levels during muscle activity without inhibiting glycolysis and the Krebs cycle. Creatine supplementation increases creatine phosphate levels, improving performance in high-intensity exercises like powerlifting and sprinting.

What are the two amino acids from which creatine is derived?

• Lysine and Methionine

• Glycine and Arginine

• Leucine and Valine

• Histidine and Serine

What is the primary function of the enzyme creatine kinase?

• To synthesize creatine from carbohydrates

• To transfer phosphate from ATP to creatine

• To convert creatine into glucose

• To break down creatine into amino acids

How does creatine phosphate help in maintaining ATP levels during muscle activity?

• By directly producing ATP

• By inhibiting glycolysis

• By acting as a buffer to prevent ATP inhibition

• By converting into glucose

Why is creatine phosphate preferred over ATP for storing high-energy phosphate in muscle cells?

• It is more stable than ATP

• It does not inhibit glycolysis and the Krebs cycle

• It is cheaper to produce

• It is easier to transport in the bloodstream

What happens to creatine phosphate levels during rest?

• They remain constant

• They decrease significantly

• They convert into glucose

• They increase as ATP is stored on creatine

During high-intensity exercise, what role does creatine phosphate play?

• It regenerates ATP from ADP

• It converts into lactic acid

• It breaks down into amino acids

• It inhibits muscle contraction

What is the primary benefit of having high levels of creatine phosphate during exercise?

• Decreased protein synthesis

• Enhanced muscle contraction efficiency

• Reduced oxygen consumption

• Increased muscle fatigue

What is the effect of creatine supplementation on exercise performance?

• It increases creatine phosphate levels

• It decreases muscle mass

• It reduces energy levels

• It inhibits ATP production

How does creatine supplementation affect the equilibrium of the creatine kinase reaction?

• It shifts the equilibrium to the right

• It stops the reaction completely

• It has no effect on the equilibrium

• It shifts the equilibrium to the left

Which principle explains the shift in equilibrium due to creatine supplementation?

• The Principle of Least Action

• The Law of Conservation of Energy

• Newton's Third Law

• Le Chatelier's Principle