The correct answer is: B) nodes of Ranvier.
Schwann cells are non-neural cells that are part of the peripheral nervous system with supportive function for neurons. In myelinated axons, Schwann cells form the myelin sheath that is not continuous. The tiny gaps between adjacent Schwann cells are called nodes of Ranvier.
Nodes of Ranvier are the spots where the axolemma (the cell membrane of an axon) is exposed to the extracellular space. Because of the presence of nodes, nerve conduction in myelinated axons is referred to as saltatory conduction.
Answer:
This signifies that the protein primarily comprises multiple polypeptide chains connected together with the help of disulfide bonds. The enzymes may be found in the form of dimers, trimers, or tetramers. Various examples of dimers, trimers, and tetramer proteins are known, of them, NEMOs dimers are considered to be held by disulfide bonds.
Thus, it can be hypothesized that the enzyme under examination is a multimer held in combination by disulfide bonds, with each comprising catalytic sites. On breaking of disulfide bonds, the enzyme dissociates into its many single units.
This illustrates the reduction in catalytic activity. Each active site in a single unit will work, however, at a gradual rate. This also shows detection of multiple globular proteins after disulfide reduction.
Answer: D. A river separates members of a squirrel population that used to occupy the same geographical area.
Explanation:
Allopathic Speciation occurs when a geographic barrier (river, mountain, or canyon) separates members of a population
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