Validity is whether the method addresses the aim, I assume that the aim was to produce the ester ethyl ethanoate. Provided the method leads to this it should be valid.
Hope it helped
My teacher used this analogy, the b cells are like hitmen. They get a picture of the target (the antigen) and then they start sh*ting out antibodies that immobilise the virus or bacteria so that it cannot move or multiply, they immobilise them long enough so that the white blood cells that are...
Biology 5th edition by Mitchell, Campbell and Reece as well as https://www.youtube.com/watch?v=MVZC1mQkvmw
I highly suggest you take a look around your local library and find some books on cholera if possible.
When the bacteria for cholera is consumed the stomach acids usually kills most of them, however some will survive, even if it is only one bacteria. Since the small intestines have a slightly basic pH cholera can land their and undergo binary fission. It then begins to release a toxin called...
For chemistry all you have to do is follow the syllabus that can be found on the BOSTES website. What I would recommend is that you get a new book and write notes on every dot point, both left and right hand side, as well as properly filing your practicals with results. Once you have done the...
The main component of doing well is to understand everything, if you understand everything you will practically memorise it. Also this helps with your waffling skills so if you hit a roadblock you will at least get a mark or two.
The second tip is to use the syllabus and look at other...
To measure a rbc first you must set up the light microscope appropriately. The magnification really doesn't matter so long as you manage to spot the cells, but I would recommend using a X40 magnification. Once you can see the cells you use grid paper or a ruler to measure the field of view or...
An advantage is that artificial blood reduces blood born diseases such as AIDS and hepatitis, in addition it is also non specific and can be used for anyone rather than people with weird blood types e.g a person with O- can only get blood from another person with O- blood.
A disadvantage is...
I'd have to say that it is recessive as there has been a huge gap where the trait has not been present, it is definitely not dominant as it has only appeared three times and the chances of it being sex linked is relatively low as only 1/7 of the males born have the trait and they have a 50%...
You could also use a arterial blood gas analysis which is essentially a invasive technology that involves taking a same of the patients blood and then analysing the pH of the blood through a blood gas analyser to determine the carbon dioxide levels. This technology if the physician suspects that...