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2

There is no standard notation called Q (matrix). However in this case I think the matrix that they are referring to is the state transition matrix (similar to the adjacency matrix as mentioned by Justas in the comments, but with rates instead of just the connections). Basically you have three states (lets call them A, B and C) and there is a rate for ...


0

First off, AOZ has a wonderful page about titanium alloy uses in medical applications you should read and that most of my info is coming from: Suitability of Titanium for Implant Purposes I think you're having a couple of easy to correct misconceptions. First, titanium alloys are used for medical implants and replacements because they're lightweight, ...


2

In organisms which have haploid males (such as honeybees), there is a variation of meiosis during spermatogenesis. The meiosis-I is abortive i.e. the chromosomal events such as crossover and separation of homologous chromosomes, do not happen. However, some cytological changes do happen which is described by Sharma et al (1961) as "simulation of the normal ...


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Organisms which grow from parthenogenesis (without fertilization) produce gametes by mitosis. Some examples are rotifers (bdelloid rotifers), crustaceans (water flea), honey bees, some birds (turkeys), etc. Parthenogenesis is a natural form of asexual reproduction in which growth and development of embryos occur without fertilization. In animals, ...


33

Short answer It is a flying lemur (there exist only 2 species). Flying lemurs and primates are together a sister clade to treeshrews. Easy source of information Have a look at onezoom.org or tolweb.org by yourself! onezoom.org is more recent and clearly more trustful. It has the default of showing only fractions of the whole tree of life though. Tree of ...


22

The most closely related animals to primates are colugos (order Dermoptera). The next most closely related after colugos are tree shrews (order Scandentia). The next most closely related after tree shrews are rodents (order Rodentia) and lagomorphs (order Lagomorpha) (rabbits, hares, and pikas). Sources: Wikipedia's section on the evolutionary history ...


0

I'm not quite clear what the question is asking, as far as I can see, one pair would be enough.. Since your primers don't include the distinguishing base (and it would be dicey to e expect a PCR reaction to totally fail because of a one base difference) I assume you are going to do sequencing or digest after the PCR to distinguish between the species?


1

You do need two pairs of primers one unique to each species as you need a positive result to be confident that the thing you are looking for (cow or horse) is there. There is no limitation on them being in the same place (with a different last base). Usually this would be analyised by gel-electrophoresis and not by sequencing so you don't have to worry ...


0

1) You know most bridges have vertical cylindrical pillars. This is probably because cylinder is among the strongest 3D structures to support anything. So, cylindrical trunk provide best support for tree crown. 2) Most accurate It is natural for any cell to grow equally in all directions. This, leads cells to expand in all directions equally in a circular ...


2

The correct answer would be a) rising pCO2. The rising CO2 level in the blood causes an urge to inhale and take in more O2. For how it works, this is controlled by respiratory center: The respiratory centers (RC) are located in the medulla oblongata and pons, which are part of the brain stem. The RCs receive controlling signals of neural, chemical and ...


4

I recommend to filter using transcript_type value from description column. You need only proteine_coding genes. Now you have extra ~10K unprocessed pseudogenes, ~5K antisense genes, ~4K miRNA, ~7K lincRNA and more than thirty other categories of unprocessed pseudogenic stuff. As far as I know current release for GRCh37 is 19th version, not 18.


4

From http://education.nationalgeographic.org/encyclopedia: A keystone species is a plant or animal that plays a unique and crucial role in the way an ecosystem functions. Without keystone species, the ecosystem would be dramatically different or cease to exist altogether. [...] The sea otter is an example of a keystone species in the Pacific ...



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