Answer:
Option (2).
Explanation:
Ames test is used to identify the mutageneicity of the compound. The bacteria are treated with chemicals in the nutritive environment to determine whether the substance can acts as a mutagen or not.
The bacteria that can restore the biosyntheic activity in the environment can be considered as mutagen. The mutant bacteria can be easily identified in the Ames test.
Thus, the correct answer is option (2).
Answer:
Chemical weathering
Explanation:
Chemical weathering is the process when rain chemicals react with rocks and minerals. In this process, the rocks are weakened. This chemical happening provokes the chemical reaction in the rock or in the mineral.
Chemical weathering is a spontaneous process and it leads to a more stable state for natural materials under a given set of conditions.
Answer:
Myelination
Explanation:
The covering of myelin around the axons is called the myelin sheath. This myelin sheath helps in transfer of information faster and also in complex processes of the brain. The process of myelination begins in the PNS (peripheral nervous system).
The myelinated section are seperated from each other with a gap called nodes of ranvier. Glial cells (oligodendrocytes) forms the myelin sheath in the central nervous system and schwann cells (glial cells) forms the myelin sheath in peripheral nervous system. The propagation of electrical impulse in the myelinated fibers is by saltatory conduction that is from one node to another.