Answer:
To observe the cheek cell,
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Take a tooth pick use its blunt side to scrap inside the mouth.
- You will see some deposition on the blunt side of tooth pick, make a smear on the clean slide in the center using that tooth pick.
- Add a drop of methylene blue solution and place a coverslip, make sure that bubbles are avoided i.e. coverslip should be placed in the inclined manner.
- Remove the excess solution and observe it under the microscope first under 4X and then under 10X.
Observation:
- The cells observed are squamous epithelial cells. The small blue dots seen inside will be the bacteria from our teeth and mouth.
The answer is D because <span>In </span>exocytosis<span>, materials are </span>exported<span> out of the cell via secretory vesicles. In this process, the Golgi complex packages macromolecules into transport vesicles that travel to and fuse with the plasma membrane. This fusion causes the vesicle to spill its contents out of the cell. Exocytosis is important in expulsion of waste materials out of the cell and in the secretion of cellular products such as digestive enzymes or hormones.</span>
One advantage of genetic engineering is the production of valuable proteins: recombinant DNA made possible the use of bacteria to produce proteins of medical importance such as genetically engineered human insulin which is of great importance.
Another advantage is the production of vaccines. Vaccines produced by genetic engineering offer an advantage that the microbial strains from which proteins are extracted do not contain complete viruses and thus there is no risk of accidental inoculation with live virus.