Biochemistry Option: Section B8 Nucleic acids

The nucleic acids section of the biochemistry option now has personal significance for me. Towards the end of last year, I was diagnosed as having type 2 diabetes. This came as a bit of a shock to me. I was not overweight and have a relatively healthy BMI of 23.6. However, after a bit of digging round into my family’s history I found out that on my father’s side of the family, his brother (my uncle), his mother (my grandmother) ...

Diabetes

This section of the option now has significant personal significance for me. At the end of November 2018, I was diagnosed with diabetes. Initially, this came as something of a shock to me. I eat a healthy diet, don’t drink too much and am not overweight (I have a relatively healthy BMI of 23.6). Naturally, the doctors and hospital staff wanted to find out more. There are two types of diabetes, imaginatively titled type 1 and type 2. In simple terms, ...

The Halogens

Topic 3.2 of the periodic table deals with periodic trends. In particular, under the applications and skills section, we are told to 'discuss the similarities and differences in the properties of elements in the same group, with reference to the halogens (group 17).' In this month’s blog, I thought I would share with you my way of teaching this particular aspect of the course. It goes without saying that the halogens are toxic, poisonous and in general pretty nasty. You the teacher ...

Dunning Kruger Analysis

Dunning who? Dunning Kruger Analysis is doing the rounds in my school – it's the current buzz phrase. I've been in this game for too long and am always sceptical of new initiatives, but this one did catch my eye and I think it has some mileage. The theory has been around for nearly 20 years and was first applied, like a lot of the new ideas coming into teaching via business models. The idea works by applying the idea the people who do ...

What Is Entropy?

Entropy is covered in the AHL part of the course: Topic 15.1 in the energetics / thermochemistry unit. The entropy change (symbol = S) in a chemical reaction is determined by as follows: total entropy change = total entropy of products – total entropy of the reactants You will have probably been taught that entropy is a measure of disorder. Order goes to disorder. The universe is expanding (and therefore getting more disordered). Liquid water has a greater entropy than solid water (ice) ...

Benzene

Benzene is sometimes referred to as an aromatic compound as opposed to the majority of other organic molecules that you have so far studied that are found in chains and sometimes referred to as aliphatic compounds. Aromatic substances are said to have an unsaturated ring of atoms whereas aliphatic substances open chains. The word ‘arene’ is sometimes used in place of aromatic. Benzene has the formula C6H6. Its structure was first proposed by the German chemist Friedrich August Kekulé in 1865. Its ...

The Avogadro Project

This sounds like some sort of clandestine secret government project I think but in fact, it is something far more interesting! The Avogadro projects earliest rumblings began in the 1990’s and were linked in with defining the kilogram. Its results were published in January 2011 and updated in 2015. The ultimate aim of the project was to provide the most accurate determination ever of the Avogadro constant. It involved an international collaboration of many scientists. As nearly all good IB students will ...

Nobel Prize in Chemistry and HL Biochemistry

This years Nobel prize in chemistry has been awarded to three researchers, Frances Arnold, George Smith and Gregory Winter for their work on enzyme research. Their work uses a technique called ‘directed evolution’ to create new enzymes. It does also tie in nicely with some of the subject material covered in the HL biochemistry option. As I understand it, the work involves causing a gene (in a bacteria) to mutate randomly by using chemical mutagens or a technique called PCR. The ...

Possible EE / IA project

By Wednesday, October 3, 2018 , , , 0

I’ve just stumbled upon a great article on the BBC website. The article can be found here: https://www.bbc.co.uk/news/science-environment-45398434 The article is about a group of plants that have evolved to take up toxic metal ions into their systems. The metals in question are nickel and zinc and usually, these ions would be toxic to plants, even in relatively small concentrations. Plants that have this ability are referred to as hyperaccumulators. One tree in particular, the rare Pycnandra acuminate produces a latex that is ...

Energy Levels

I’ve just finished teaching this topic to my students. I always find it an interesting topic to teach as the ideas used are so different to those you are probably taught prior to IB. Just when you were happy with the idea that atoms have electrons in shells you suddenly get told that this is not the case and that you need to know and use another model of the atom. It’s a great example of a paradigm shift (you will ...