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competence is the phenomenon exhibited by the cell during the particular stage of cell cycle by bacteria....it is log phase. During this stage the cell can accept any foreign DNA to enter in to it...so cell are grown upto the log phase or mid log phase and then transformed with the plasmid DNA
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What is the action of cacl2 to make a bacterial cell competent?
This is because the Ca ions being positively charged attack both the negatively charged DNA and also the lipopolysaccharide membrane. Thus, the DNA can then pass through the cell on subsequent heat shock treatment.
What is the mechanism in which ATP is used to move sodium out of the cell and potassium into the cell restores the resting membrane voltage and intracellular ionic concentrations?
Repolarization The questioner was looking for the mechanism not the process. The answer is the sodium potassium pump.
How does the acid growth hypothesis explain the working mechanism of auxin?
stretching the affected cell walls
What function of magnesium chloride in making competent cells?
Since E. coli is not naturally transformable, the ability to take up DNA or competency must be induced by chemical methods using divalent and multivalent cations (calcium, magnesium, manganese, rubidium, or hexamine cobalt) . Alteration in the permeability of the membranes allows DNA to cross the cell envelope of E. coli which is composed of an outer membrane, an inner membrane, and a cell wall. The outer membrane of E. coli can be understood by application of the fluid mosaic model for membranes and is composed of phospholipids, proteins, and lipopolysaccharides. Many channels or zones of adhesions are formed by the fusion of the outer membrane and the inner membrane through the cell wall layer. Although the transformation mechanism is not known, previous studies indicate that these channels allow for the transport of DNA molecules across the cell membrane. The negative charges of the incoming DNA, however, are repelled by the negatively charged portions of the macromolecules on the bacterium's outer surface. The addition of CaCl2 serves to neutralize the unfavorable interactions between the DNA and the polyanions of the outer layer. The DNA and competent cells are further incubated on ice for thirty minutes to stabilize the lipid membrane and allow for increased interactions between calcium ions and the negative components of the cell. The reaction mixture is then exposed to a brief period of heat-shock at 42oC. The change in temperature alters the fluidity of the semi-crystalline membrane state achieved at 0oC thus allowing the DNA molecule to enter the cell through the zone of adhesion .Prior studies showed that some E. coli strains are more susceptible to transformation than others due to differences in the composition of the lipopolysaccharide. E. coli with a lengthy O-linked polysaccharide blocks or hinders DNA from entering the cell. Adding magnesium to the media increases transformation yield by enhancing the ionic interaction of the molecules on the surface and therefore alters the suppleness of the membrane for more efficient transformation.
What advantages does hanging drop preparation have over a wet mount preparation?
Hanging drop slide is more resistant to evaporation because of the concave depression of the slide placed over the cells along with the petroleum jelly prevents drying. Wet mounts can dry out fairly quickly.
Why use glycerol in competent cell preparation?
Glycerol is a cryo preservative gives density for samples to settle in well
What is the action of cacl2 to make a bacterial cell competent?
This is because the Ca ions being positively charged attack both the negatively charged DNA and also the lipopolysaccharide membrane. Thus, the DNA can then pass through the cell on subsequent heat shock treatment.
How do you send plasmids to cell?
Herat shock and treating the cells with CaCl2
What does transformation and competent and plasmid mean?
transformation is to introduce a foreign DNA segment to a competent cell. competent cell means a cell that have ability to take a foreign DNA. plasmid is genetic element that one can integrate a DNA segment. it has its promoter, resistance gene, multiple cloning site...
How molecular mechanism of bacterial transformation is carried out?
Basically, transformation refers to the uptake and incorporation of naked genetic material by a competent cell. Most bacterial cells are not naturally competent(able to take up naked genetic material). The kinds that are use a type 4 pilli to get the genetic material into the cell. This process is very rare in nature, since it requires naked genetic material to be present, from a lysed cell, as well as a competent cell to take up the genetic material. When the DNA/RNA is taken up, it is often degraded by restriction enzymes. If it is not degraded it can exist as extra chromosomal DNA, much like a plasmid, or it can be incorporated into the cells chromosome. Scientists use heat, pH, or osmotic shock in lab to make cells artificially competent.
What is mechanism of electrochemical cell?
I don't
Cellular transport mechanism that depends upon transporters or carrier enzymes in the cell membrane?
Protein the the cell that moves mechanism. This cell also carries enzymes in the membrane.
Cellular transport mechanism that depends upon transporters or carrier enzymes in the cell membrane is?
Protein is the cell that moves mechanism the depends on movement. This cell carries enzymes in the membrane.
How is mechanism important to cell survival?
rrr
What is the definition of competent cells and how it can help to make a transformation more efficient during the cloning of desired gene?
Generally most of the bacteria have the ability to take up DNA which is present freely in the environment. This is called Competence. It is genetically acquired. But some cells do not exhibit natural competence and they are treated with a suitable chemical like CaCl2 to make their cell wall relatively permeable to DNA. We can make any cell competent in vitro and introduce our desired gene which is taken up by the competent cell. To test the efficiency of our treatment, we may introduce a marker gene like gene for antibiotic resistance such as Tetracyclin onto the desired gene and grow the treated cells on Tetracyclin medium so that only the cells that have taken up the DNA survive.
What is connecting mechanism of nervous system?
connecting mechanism is the part of female that reproduce egg cell
The process of a cell's nucleus replicating and dividing in preparation for the division of the cell is called?
mitosis
