Answer:
Antibiotic resistance can evolved in bacterial population in the following ways:
Explanation:
- In response to constant exposure to antibiotics some members of a bacterial population develop some beneficial mutations in some essential genes that gives them survival advantage in terms of food and space over the sensitive bacterial strains and hence they are capable of out-competing the sensitive bacteria.
- This happens due to the process of Natural Selection.
- These genes are called antibiotic resistance genes and bacteria usually carry them on plasmids in form of cassettes where genes resistant to multiple drugs are incorporated. These plasmids are called the MDR or Multi-Drug Resistance Plasmids.
- These resistant plasmids can be easily transferred among bacterial populations by conjugation, transformation or transduction or direct plasmid transfer.
- The resistant genes encode for proteins that render the drug ineffective by promoting their efflux from the cells, preventing their entry into the cell, chemically modifying them such that they become non-functional or altering the target site of the drug.
A mitotic inhibitor chemotherapy drug would cause the DNA to break during the early stages of cell division. Mitotic inhibitors are drugs derived from natural plant sources, and work by inhibiting cell division or mitosis, where a single cell divides into two genetically identical daughter cells. They may bind to tubulin and inhibit its polemerization into microtubules.
Answer:
The corpus callosum
Explanation:
The corpus callosum is the largest white matter structure in the brain. It is located beneath the cerebral cortex and it connects the left and right cerebral hemispheres thus enabling communication between them. The corpus callosum is a bundle of nerve fibers, (axon projections) which transmits neural signals.
It is a rare genetic mutation that both the maternal and paternal partners have to be at least a carrier for the albinism gene.
Trees are very important natural resources. They are the source of food, shelter and habitat. We get various woods, timber , fodder from the forest. Trees hold the soil firmly. Forests helps in conducting water cycle. If trees are cut down then environmental pollution will increase because trees purify the Air. Land pollution , air pollution , water pollution may increase. Biodiversity can be affected.
