Each sieve tube element is normally associated with one or more nucleated companion cells, to which they are connected by plasnodesmata (channels between the cells). Each companion cell is derived from the same mother cell as its associated sieve tube member. Sieve tube members have no cell nucleus, ribosomes, or vacues. Thus, they depend on companion cells to provide proteins, ATP, and signalling molecules
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When every dilution of your sample results in a plate that is too few to count we should filter the original sample and use most probable number method .
Probable number method count and determine the number of bacteria in a culture, plate aliquots of the dilutions onto agar with sterile pipettes, spread with glass sticks, incubate at 37°C and count the number of colonies. It is imperative that you utilize your best culture technique.
Not all bacterial cells produce colonies, as some bacteria tend to clump or aggregate, and some are nonviable. For this reason results are reported as colony forming units (CFU)/ml of bacterial culture. Ideally only plates with 25-250 colonies are used.
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Chemotherapy is a term which we usually related to the treatment of cancer. In cancer the malignant cell keeps on dividing themselves and also infect the near by cell to enter into a phase of no restrictive division. In chemotherapy, a drug or medicine either individually or in combination with other medicines is either directly introduced in the blood or is injected only on the targeted cell. The chemotherapy interacts with the cell division process of the cell directly or indirectly. In the direct process the cell division process either mitosis or meiosis is impaired or the essential hormones or enzymes required for cell divisions are attacked through cytotoxic drug. It also inhibits cell division through apoptosis strategy where the cancerous cell starts dividing themselves. The chemotherapy process is to be done regularly over a certain period of time. Usually the treatment course occurs from a day to few weeks’ time. The dosage of chemical is given either orally or injected into the body fluid or either through intravenously.
Apart from benefits there can be several side effects of chemotherapy:
a) A patient may get pucky feelings and in some cases may have nausea or vomiting
b) There are also chances of hair loss.
c) It can also adversely affect the skin, as it may get dry or oversensitive.
d) The blood platelet count may decrease
e) There can be chances of hearing and vision impairment.