Ans.
Paper waste prevention is defined as a practice to reduce or eliminate use of paper, which is potential for the efficient use or disposal of paper. It decreases the environmental impacts due to both paper manufacturing and paper recycling, such as demands on forest resources).
Use of advance technologies, such as E-mail (electronic mail) can help in cut down on paper waste. Nowadays, E-mail has replaced conventional letters and faxes as it is more eco-friendly than letters and faxes, which needs paper consumption.
Thus, the correct answer is 'option d). E-mail.'
Answer:
The correct answer is - osmosis.
Explanation:
Paramecium lives in freshwater like the Potomac River which is hypotonic to the cytosol of the paramecium. Paramecium uses contractile vacuoles to transport the water from the lower concentration (outside of the cell) to a high concentration of solvent to the inside of the cells.
This process of cell transport is carried out by osmosis as their cytoplasm contains a higher concentration of solutes outside the cell. This excess water is collected into vacuoles called contractile vacuole that swells and finally internalized the water to the outside of the cell.
Thus, the correct answer is - osmosis.
Answer:
The correct answer will be option-B.
Explanation:
Sertoli cells are the large somatic cells present in the testis which helps in the formation of spermatozoa. The Sertoli cells create a suitable environment for the production and maturation of the sperms as they produce certain molecules which nourishes the sperms.
The Sertoli cells act as a barrier between the testis and blood and secrete enzymes like inhibin. They eliminate the apoptotic germ cells and also produce seminiferous fluid to nourish the sperm. They do not play any role in primary spermatocytes.
Thus, Option-B is the correct answer.
Anything prokaryotic doesn't contain a nucleus
