Biology is everywhere, can't you see it?
Saturday 15 December 2018
When students say that they don't have any idea what they would like to investigate for their Individual investigation, I'm surprised. "What do you mean? There is Biology everywhere you look, can't you see it?"
Then I remember, I'm a bit of an enthusiast and I might be talking to a student who loves History, more than Biology. (Perish the thought!)
How often do we take examples from an IB student's world to illustrate how the Biology we have learned is involved in the world around us?
Do we spent enough time in IB Biology lessons showing students how to look for it? Is there time for this?
This blog post attempts to illustrate how easily we could include a few pointers to students helping them to see the Biology which is all around them. A photo and a few provocative questions could be enough to get students asking questions about their everyday lives and thinking of explanations which require some IB Biology.
If we showed these at relevant points of the Biology course students might begin to recognise more of the Biology all around them.
This story could illustrate one of these IB Biology topics
- 1.2 Prokaryote cell structure - why does hand sanitiser kill bacteria?
- 1.3 Integral proteins in plasma membranes - how denatured protein could bust the cell
- 2.4 Protein structure - how alcohol might denature proteins
- 3.1 The effect of a mutation on protein structure
- 5.2 Evolutions of resistance to an antibacterial chemical
Germ Panic is a powerful marketing tool - for hand sanitisers.
There are a lot of adverts for hand sanitiser around. Do any of you use a hand sanitiser?
How true are the claims in each of these adverts?
How do hand sanitisers actually kill prokaryotes? (1.2, 1.3 or 1.4)
The revenge of the superbugs!
Look at the numbers: Hand wash removes 99.9% of germs (pathogens) Great! But is that good enough?
When we have a chest infection we can produce 40000 airborne droplets from sneezing (Nicas et al. (2005))
There can be 3700000 pathogens per ml of lung fluid
If hand sanitiser kills 99.9% of pathogens 0.1% of 3 700 000 will survive?
That leaves 3700 surviving pathogens. In prokaryotes the lifecycle is rapid and evolution can happen quickly.
Could the survivors of our hand sanitisers be evolving resistance to the alcohol in these products? (3.1 or 5.2)
Should we be using hand sanitisers or washing hands with soap?
Read more about it
A scientific paper estimating numbers of pathogens in sneezes: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2894888/