How do you calculate the burst size of a cell after it's been infected with bacteriophages?
957348
The specific answer to that question can be found when you Google "burst size bacteriophage"....and select first line entitled\n"Bacteriophage Lecture Notes".....go down a few lines and it gives exact details.\n\nHope this helps.
913686
This is a simple ratio problem. The equation would be Dgalaxy/Dearth=Dearth/x so x=(Dearth)^2/Dgalaxy. Asssuming a parsec is 3.6 light years, and a light year is 5.87 trillion miles and the diameter of the Earth is 8,000 miles, then the Earth would be 0.001 millimeter or one micron in size, which is the size of an average bacterium, maybe? Very cool. Oops! I re-did my calculation and I see that I made a factor of ten error. The correct answer is about 0.1 microns, or the size of some viruses. But tell me how you would make such a model of the Earth?
977857
The population can be modelled using the following equation.\nP(t) = P(initial) * 2^(t/10)\n\nYou know P(90) = 90000:\nSo plug this in:\nP(90) = 90000 = P(initial) * 2^(90/10)\n\n90000 = P(initial) * 2^9\n\nSolve for P(initial):\nP(initial) = 90000 / 512\nP(initial) = 175.78125\n\nHere are the details:\nP(0) = 175.78125\nP(10) = 351.5625\nP(20) = 703.125\nP(30) = 1,406.25\nP(40) = 2,812.5\nP(50) = 5,625\nP(60) = 11,250\nP(70) = 22,500\nP(80) = 45,000\nP(90) = 90,000\n\nYou can also do this working backwards, just dividing by 2.  So at time t = 80, you have half the population (45,000) at t = 70 you have half of that (22,500), etc.  Until you get to t = 0.\n\nSo the answer is:\nInitial population = 175.78125 ≈ 176 bacteria
753317
Bored at work:\n\nYou could look for reverse transcriptase activity in infected cells.  This is a sure sign of RNA being turned into DNA.\n\nYou could purify virus from the aftermath of infected cells.  Then set up experiments to determine the nature of what you've isolated and what its properties are.
908586
GB >= 0.6*(CS + GB)\n\n"cushion" variable U introduced : \n\nU >= 0 \nGB + U = 0.6 * (CS + GB)
603453
A cell culture is just a vial/petri dish/growth chamber with living cells it it.  You infect the cells with your virus and the virus will multiply and lyse the cells on its own.  Eventually you will have lots of virus and no cells. The amount produced will depend on the number of cells in the medium and the number of copies the virus makes per cell.
182868
Depends on the cell type labile, stable, non regenerative etc
669691
different viruses have different needs, but all share a common one - they need a host cell. some viruses can only be cultivated in one specific cell type, while others can multiply in many different types. this depends on the viruses' proteins and the host cell receptors. once you found a cell type that has the receptors which "invite" the virus in, all you need is the nutrients for the cell, and growth factors. there are many different nutrients and factors needed. using an animal serum (bovine serum is commonly used) you can usually get all the factors needed, but it is important that the serum is "cleaned" from any immune proteins and foreign cells.\nthen, you mix the virus in a liquid buffer with the cells, and incubate them (if it's a human virus, 37 degrees Celsius will usually be optimal). different viruses require different incubating times, which can vary between hours to days. now, if you want to see if the viruses have infected the cells you can use several methods, the simplest of which are:\n1. if the cells were in one layer, and the viruses are of a kind that causes lysis (breaking down) of the cells, you will see "holes" in the layer - each hole representing one virus from the original buffer, which multiplied.\n2. using a microscope, you can see inside the cells small bodies called inclusion bodies. these are typical for every virus family, and can help you learn which virus it was that infected your cells.\nhave fun, and use gloves...:)
670441
The volume of the virus is pi*(200^2)* 1500=1.884*10^7 cubic angstroms.   This goes into.24 cc 1.27*10^16 times.Divide 1 gm. by this figure and you get the weight of 1 virus=7.87*10^-17 grams.   That's the weight of a few million hydrogen atoms, which sounds about right.
85370
C/I = (r/(D-r)) ^ -4\n\nWhere C/I is the co-channel interference protection ratio, r is the cell diameter, D is the distance between similar cells in adjacent patterns.  See equation 9-6, page 527 of the reference in "Source(s)".
734519
(1) Take a container and measure the length of the container. Let us say the length of the container is L. \n\n(2) Take a beam of light (preferably a monochromatic source like laser beam) and shine it through the empty container. \n\n(3) Measure the intensity of the light at the end where the beam has gone through the empty container. Let this be Io. \n\n(4) Now fill the container with the liquid whose molar extinction coefficient is unknown. Now measure the light intensity as the beam travels the length L of the container. The measured intensity is I.\n\n(5) Beer-Lamberts law is I=Io exp(-a L) where all the quantities have been experimentally determined except a which is the extinction coefficient. \nRearrange the above formula and we get, a=(-1/L)*log(I/Io) where log is to the base e.
394349
This article might help if you reproduce their test system:\nhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15159161&dopt=Abstract
310534
Ascospore length and breadth:  27-30 x 13-15 um\nAscus size at maturity:  15-18 x 180-200 um\nDiameter of pore at ascus apex:  3-4 um through which the 15 um ascospores are forcefully ejected\n\nGood question...very hard to find answer :)
492856
a host.\n\nA virus is a submicroscopic parasitic particle that infects cells in biological organisms. The study of viruses is virology.\n\nViruses are obligate intracellular parasites that lack the cellular machinery for self-reproduction. Viruses infect eukaryotes and prokaryotes such as bacteria; viruses infecting prokaryotes are also known as bacteriophages or phages. Typically viruses carry a small amount of genetic material, either in the form of DNA or RNA or both, surrounded by some form of protective coat consisting of proteins, lipids, glycoproteins or a combination. The viral genome codes for the proteins that constitute this protective coat, as well as for those proteins required for viral reproduction that are not provided by the host cell.\n\nViruses are non-living particles that can only reproduce when an organism reproduces the viral RNA or DNA. Viruses are considered non-living by the majority of virologists because they do not meet all the criteria of the generally accepted definition of life. Among other factors, viruses do not move or metabolize on their own. However, a comprehensive definition of life is still somewhat elusive since some bacteria (considered living) like rickettsia exhibit both characteristics of living and non-living particles.\n\n\nLife cycle\nAttachment, sometimes called adsorption: The virus attaches to receptors on the host cell wall. \nInjection: The nucleic acid of the virus moves through the plasma membrane and into the cytoplasm of the host cell. The capsid of a phage, a bacterial virus, remains on the outside. In contrast, many viruses that infect animal cells enter the host cell intact. \nTranscription: Within minutes of phage entry into a host cell, a portion is transcribed into mRNA, which is then translated into proteins specific for the infecting phage. \nReplication: The viral genome contains all the information necessary to produce new viruses. Once inside the host cell, the virus induces the host cell to synthesize the necessary components for its replication. \nAssembly: The newly synthesized viral components are assembled into new viruses. \nRelease: Assembled viruses are released from the cell and can now infect other cells, and the process begins again. \nWhen the virus has taken over the cell, it immediately causes the host to begin manufacturing the proteins necessary for virus reproduction. Some viruses, like herpes, cause the host to produce three kinds of proteins: early proteins, enzymes used in nucleic acid replication; late proteins, proteins used to construct the virus coat; and lytic proteins, enzymes used to break open the cell for viral exit. The final viral product is assembled spontaneously, that is, the parts are made separately by the host and are joined together by chance. This self-assembly is often aided by molecular chaperones, or proteins made by the host that help the capsid parts come together.\n\nThe new viruses then leave the cell either by exocytosis or by lysis. Envelope-bound animal viruses cause the host's endoplasmic reticulum to make certain proteins, called glycoproteins, which then collect in clumps along the cell membrane. The virus is then discharged from the cell at these exit sites, referred to as exocytosis. On the other hand, bacteriophages must break open, or lyse, the cell to exit. To do this, the phages have a gene that codes for an enzyme called lysozyme. This enzyme breaks down the cell wall, causing the cell to swell and burst. The new viruses are released into the environment, killing the host cell in the process
512055
2,800\n\nYour original solution is one tenth of a mL, so multiply that by ten to get the end volume.  Do the same thing with the number of particles: 280x10=2,800.
964421
All organelle sizes in micrometers are available at http://teachersnetwork.org/ntol/lessons/plantcell/index.htm \n\n( scroll down to the table near the end )
441197
a small volume (1 to 10 ml) of blood is taken, cultured in medium containing a mitogen(to induce WBCs to divide)and placed in a 37 c incubator for about 72 hours. Then a mitosis-arresting agent is added. After treatment with a hypotonic solution like 0.075M KCL(so that the cells will swell and chromosomes spread)the cells are fixed with a fixative (usually made from one part acetic acid to three part methanol)and mixed thoroughly.then a drop of this cell suspension is put on a slide and placed on a hotplate(or in an oven overnight).Harvesting means the step after KCL treatment, when you add fixative.