what does the term "BL21" and "DE3" in the E. coli BL21(DE3)cells stand for?
439627
It's a strain designation.  BL21 is deficient in a protease, and DE3 can be used with vectors containing the CcdB gene, which is toxic to other bacteria.
19476
Algae and higher plants are called eukaryotic.  They tend to have two different types of genetic material, one located in the nucleus and a different type located in the cell’s mitochondrion.  Bacteria, on the other hand, are called prokaryotic.  They only contain one type of genetic material.  Some bacteria’s genetic material resembles that found in the nucleus of eukaryotic cells.  Some bacteria DNA or RNA more closely resembles that of mitochondrion.\nProper cleavage of the genetic material, followed by TLC or possibly paper chromatography, could show the similarities or differences.  This could be used to infer (not prove) any evolutionary relationships.
430980
the first one is RNA. You can tell by the U at the end of the sequence
813729
plasma membrane-bouncer or security\ncell wall-Berlin Wall\nmitochondria-power plant\nER-Ups of the cell\nlysosome-decomposers\nvacuole-water and septic tank\nchloroplast-dye
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Wow, this answer is gonna be a long one...   There are numerous studies of the charting of the positions of genes on a DNA molecule or chromosome and the distance between genes of Escherisia Coli. It basically comes down to good old conjugation and transduction.  Having sequenced the E. coli K-12 genome, scienctists are creating a knockout of every gene, a clone of every ORF, and an extensive gene expression data set under a variety of physiological conditions. These clones and data sets are made available freely to the community.  Scienctists have also sequenced six additional enterobacterial strains which are pathogens closely related to E. coli K-12, and many plasmids. The comparative genomics aim of this effort is to characterize the gene pool of horizontally transferred elements and virulence determinants known as the pathosphere.\n\nI put a reference on it so be sure to check it out yourself. \n\nA mutator gene, mutD5, whose phenotype is conditional, has been identified in Escherichia coli. By P1 transduction it has been shown to lie at about 5.7 min on the chromosome, being co-transduced with proA and argF. In rich medium, streptomycin- and nalidixic acid-resistant mutation frequencies are 50 to 100 times higher than those in minimal medium. In minimal medium, the mutD5-induced mutation frequencies are still 50 to 100 times above co-isogenic wild-type (mut+) levels. Similar results were obtained with all markers tested. Mutant frequencies can be raised by thymidine in the medium at concentrations as low as 0.04 μM, or by the endogenous generation of thymidine from thymine plus a deoxyribosyl donor. Deoxyadenosine, various ribonucleosides, thymine, and 2-deoxyribose do not stimulate mutation. None of these effects are related to growth rate, since growth rate and mutation rate can be decoupled completely.\n\nThe gntP gene, located between the fim and uxu loci in Escherichia coli K-12, has been cloned and characterized. Nucleotide sequencing of a region encompassing the gntP gene revealed an open reading frame of 447 codons with significant homology to the Bacillus subtilis gluconate permease. Northern (RNA) blotting indicated that the gntP gene was monocistronic and was transcribed as an mRNA with an apparent molecular size of 1.54 kb. The transcriptional start point was determined by primer extension analysis. The gntP gene was found to be under catabolite repression and was not induced by gluconate. Also, expression seemed to be stringently controlled. Several observations indicated that the GntP protein is an inner membrane protein; it contains characteristic membrane-spanning regions and was isolated predominantly from the inner-membrane fraction of fractionated host cells. A topology analysis predicted a protein with 14 membrane-spanning segments. The inability of a mutant strain to grow on gluconate minimal medium could be relieved by introduction of a plasmid encoding the gntP gene. Finally, the kinetics of GntP-mediated gluconate uptake were investigated, indicating an apparent Km for gluconate of 25 microM.
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Phenotypes: AB+ or AB-\n\nAntigens: A and B\n\nGenotypes: AB (+ or -)\n\nThanks micro_girl.  I should have made that more clear.  A and B are separate proteins, and when they are both present the resulting phenotype is AB.  Sorry if my original answer was misleading.  I fixed it.
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The subscrips indicate that mulitples of the symbol they follow.  Like the AgNO3 the three means that there are 3 oxygens.  The two after the () means there are three whole molecule though, that can be placed infront as a coeffient.
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Well the endoplasmic reticulum is full of ribosomes, which create protiens.  How that relates to a cookie factory, I guess it would be the oven where the cookies are made.
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:) Actually, you are exactly right, it should pronounced:\nsix p two one dot three.\np or q indicates the arm, the next number the band, the next the subband, etc. The numbers are not decimal!!! p21 doesn't mean there is p17 or p18, that depends on the given chromosome.\nTo be honest, in everyday usage, we commonly would say six p twentyone dot three... :)
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u mean Deoxyribonucleic acid?
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The responses of microorganisms to growth-inhibiting salt concentrations have been studied extensively. In a number of cases, the effects of both salt and sugar stress on the accumulation of individual compatible solutes such as K+ and glycine betaine have been determined. However, only in a few studies have the osmolytes accumulated in salt-stressed cells been compared with those in sugar (nonionic)-stressed cells
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OPPS SORRY, I sent incomplete. Believe it or not, it is generally described as thus: The body wants to have 2/3 of the water inside the cells \n(intracellular fluid) and 1/3 of the water between the cells (extracellular) however a Teacher is probably looking for the technical name of: interstitial fluid
151941
:) Thanks for taking all the trouble in finding me to send me a question. I Feel flattered. I am not a chemist..but i would suggest that you try searching google/yahoo with the following word combination:\n1. "Voltaic cell"+experiment+laboratory\n2. "Voltaic cel"+"kitchen laboratory"\n\nand so on.. I am sure you will find some answers. good luck! I will try to pull out more answers and try to send them to you. by the way my email id is same as the handle..scientist_atlarge.
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a- multi\nb-both\nc-both (plants like bacteria and animals)\nd-single celled
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Primary cultures or immortalized cells?\nI use CF3 and they grow just fine in DMEM + 10% BCS, they have contact inhibition, so you need to split them twice a week (if they become 100% confluent, they will detach from the dish).
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http://www.microbesonline.org/operons/gnc205922.html
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Stain with ethidium bromide (careful, its a carcinogen) and photograph under uv light.\n\nMeasure the migration of the bands and those of the size reference.  Plot the migration of the size reference on semi-log paper and use the resulting curve to detemine the size of your plasmid fragments.