Explain the difference between Fischer's lock-and-key theory and Koshland's induced fit hypothesis of enzyme-substrate interaction.

True or false:

“After the products have formed, the enzyme is destroyed and cannot reused.”

Correct the statement if it is false.

Which statement(s) is/are correct regarding isoenzymes?

i. Isoenzymes are different forms of the same enzyme that catalyze the same chemical reaction but differ in their molecular structure.

ii. Isoenzymes are always identical in structure and function.

iii. Isoenzymes can vary in their kinetic properties, such as affinity for substrates and maximum reaction rates.

iv. Isoenzymes may be tissue-specific, allowing for specialized regulation and adaptation to the needs of different tissues.

A patient has come in for a routine health check-up. The blood test results indicate a high level of Aspartate Aminotransferase (AST). What could be the most likely cause of this elevation?

Which of the following statements accurately describe the interactions between cofactors (eg Mg²⁺) and ATP in the context of enzymatic reactions?

I. Cofactors such as Mg²⁺ stabilize the negative charges on ATP’s phosphate groups, facilitating their transfer.

II. Cofactors directly transfer phosphate groups from ATP to substrates during enzyme-catalyzed reactions.

III. Cofactors are required for ATP binding to the enzyme’s active site in some reactions.

IV. The interaction between ATP and cofactors is primarily due to hydrogen bonding between the two molecules.

Which of the statements are true about the interaction of amino acids in the active site of an enzyme’s primary structure?

I. The primary structure of an enzyme directly determines the specific sequence of amino acids in the active site, influencing substrate binding.

II. Amino acids in the primary structure can influence the enzyme's overall three-dimensional shape, but they do not directly affect the active site’s properties.

III. Interactions between amino acids in the active site are essential for the enzyme's specificity and catalytic activity.

IV. Changes in the primary structure of an enzyme can lead to alterations in the active site’s configuration and enzyme activity.

The enzyme carbonic anhydrase catalyzes the conversion of carbon dioxide and water into bicarbonate and a proton. Which model better explains the action of carbonic anhydrase?