The Lock-and-key mechanism was first proposed by Emil Fischer which described as the enzymatic reactions whereby an enzyme with a single substrate binds temporarily to form a substrate complex.
The lock-and-key mechanism is usually associated with the complementary shapes of an enzyme with a single substrate, wherein the lock that is being referred to is the enzyme and the substrate is the key. One right sized substrate (key) fits into the active site (key hole) of the enzyme (lock).
The active site which is mentioned above is structurally complementary to the substrate. This is the temporary binding site on the enzymes. Just like a lock and key, the enzyme as the lock and the substrate as the key is said to fit together.
Answer:
The age of the cell
Explanation:
Assuming your question was meant to be "Which of the following is NOT a difference between Prokaryotic and Eukaryotic cells?", everything except the age is different.
Prokaryotes are simple cells that have no nucleus and are generally small. Eukaryotes are complex cells that have a nucleus, organelles, and are much bigger than prokaryotes.
Both fight over infection and work on the rebuild of body tissue
