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You have several questions, please try to limit your posts to one question each. That being said, I'll try to address each of your concerns. Does the cold cause these cells to apoptose? No. The purpose of staining at 4°C and washing with cold buffer is twofold - to maintain viability (all cellular processes slow down at lower temps) and to prevent ...


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Erythrocyte metabolism is unique in that the mature erythrocyte contains no mitochondria and therefore no Kreb's cycle! Instead the energy needs of the RBC are met largely (95%) by anaerobic glycolysis in the two pathways: Embden-Meyerhof + Hexose-monophosphate. + Virginia University source


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The process you are asking about is called the termination of the immune response, and for a long time it was not studied very much for some reason, with scientists preferring to analyze initiation instead. However, this has changed in recent years, and while we still don't know a good deal, the picture is much clearer than it had been a decade or three ago. ...


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Homeothermic multicellular organisms have special tissues that burn resources to warm up (usually this involves breaking the electron-transporting chain at the final stages of respiration to transform all chemical energy into thermal energy). And they have special tissues (fat) and enough body mass (this is more about the volume/area ratio) to keep this ...


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As a preface, this isn't a comprehensive answer for everything. As MattDMo points out, some of the original answer was poor in it's presentation. In my update there's some supporting information to some expert testimonial, but this is mainly targeted at adult cases rather than pediatric cases, i.e. why would cardiac cancer be rare in an adult with no prior ...


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Ploidy and reproductive isolation in plants Speaking generally, there is simply no question that for flowering plants there can be a sexual pathway between diploid and polyploidy levels. The question is how wide is the bridge and how much flow is there in either direction. In other words the questions become "How much flow?", "How meaningful the flow?", ...


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Depending on the species the hability of generating hybrids will be different. Some can, others don't. However generating a hybrid of a diploid and a tetraploid will give rise to a triploid, usually sterile plants (as it happens with seedless whatermelons, which are a cross between tetraploid and diploid). This is where most of the isolation comes from, ...


1

But when does exactly osmosis occurs instead of diffusion? These processes are not mutually exclusive. Both can happen simultaneously. Their rates depend on different parameters such as permeability of the membrane towards water and the solutes. A semi-permeable membrane has different permeability for different molecules. There are cases when one of ...


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Here is a reference for pulling quartz glass pipettes using a custom oxy hydrogen burner. Here is a video of a commercial burner based pipette puller. Not sure what the specs are. I guess if you can melt your glass using a filament it could be easier than using a torch (a lightbulb circuit is easier to control than flame). People move to flame when ...


2

How long human egg cell grow up until sperm fuse it? Ovules are made while the female is still in the uterus of her mother. The ovules (in the form of ovarian follicles) are kept in the ovaries for a long time, and just a month before leaving the ovary (ovulation), the ovarian follicle (and the future ovule) gain in size. In other words, the ovules are ...


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Membranes provide a number of benefits to organisms: 1. They represent the bounds of organism... If not for the membrane, how would you establish the (physical) limits of the organism? Would the organism be just naked DNA (I'm using this as shorthand for (genetic material')? If it made proteins from this DNA, would they be part of the organism or just ...


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Why a bi-layer? There has been an MD simulation carried out to investigate the biophysicochemistry of spontaneous bilayer assembly. There, lipids start in random orientations. The ordered bilayers we know and love spontaneously assemble in under 100ns. It would appear that the conditions for an ordered bilayer are so favourable that they take precedence ...


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Detection of and movement according to a gradient of a chemical species is a strategy that single cells use to track a target across space. There are very many strategies of movement depending on the cell and its environment, but a common problem that while cells can sense the concentration of chemicals, they cannot sense its gradient (the direction in which ...


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From the abstract of the linked article (Guttman, 2002): We used an in vivo genetic screen to identify 13 effectors [...]. Although sharing little overall homology, the amino-terminal regions of these effectors had strikingly similar amino acid compositions. And from the body: The screen relied on the type III secretion signal and the endogenous ...


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Contrary to the other answer posted, this paper shows via microscope images that the tattoo ink is in fact absorbed into cells, and forms small intracellular round granules. Electron microscopy of untreated tattoos revealed membrane-bound pigment granules, predominantly within fibroblasts and macrophages, and occasionally in mast cells. These ...


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First, tattoo pigment isn't injected into cells. If you were to puncture a cell with something the size of a tattoo needle, it would die - full stop. Many cells are destroyed in the process though, mostly by tearing, which initiates the wound healing process. So what actually happens is the particles lodge in between the cells of the dermis (the layer below ...



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