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.
Considering the answers;
A. are still sibling species
B. shared a common ancestor more recently with each other than either did with the other two species
C.May merge into a single species if their hybrids remain fertile over the course of many generations.
D. A and B only
E. A, B, and C
The answer will be E.
If no other species can hybridize, then species W and Y are still sibling species, shared a common ancestor more recently with each other than either did with the other two species and also may merge into a single species if their hybrids remain fertile over the course of many generations.
DNA supercoiling means under or over winding of the DNA strand and basically is to become more condensed and more organized. Supercoiling is very important as it compacts the genetic code and as if that was not enough supercoiling also regulates and oversees the access the the genetic code.
It breaks down and is denatured as any other protein molecule