Answering Questions with lots of Maths in Biology - Data Analysis Questions in the new OCR Biology A Specification - updated Feb 2018 with the latest handbook

Which maths skills you need to practise for the new specification A-level Biology - excellent resources from OCR - also applies to AQA and Eduqas, lots of great practice questions

The quantity of maths in the 2017 specification is a challenge to many students - so I put together a summary of all of the OCR A new spec questions with some element of data analysis.

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A-level Results Day - August 2017 - Terrific Results and Feedback

A-level Results Day – August 2017

Results Day - always a bit nerve racking for the students (and for the teachers), more so this year with the first results for the new specification linear Biology exams, which have a very different style of assessment and far more analysis and mathematical application.  Good preparation and hard work by my students paid off.

It means a great deal to get positive feedback and hear news of success - here are some of the messages I received yesterday.

  • I got an A in biology, Thanks for all your work , I got into Notts for medicine – Mo (August 2017)

  • A*AA overall, the A* coming in Biology so very very well. This is also considering I was more uncertain with regards to how my biology went in comparison to my maths and economics. Thank you for all your help and hope to see you soon :)  - James (August 2017)

  • Just an email to say thank you so much for helping me in Biology, I got an A, so I'm over the moon!! I think from a C to an A is a great improvement. I also got As in my other subjects which means I'll be off to Durham! – Charlie (August 2017)

  • Hi tom, just checked results and I got ABB with the A being in Biology! Thanks for all your help and hope you enjoy the rest of summer. – Oliver (August 2017)

  • I got an A in Biology!! Who would've guessed considering I got an E for mocks! – Donya (August 2017)

  • Hi Tom, thank you ever so much for all your tutoring and hard work. I couldn't have got a C without you which I was really pleased with as I felt I got an E. Thank you once again – Katherine (August 2017)

  • Lydia got a grade A for biology. Thank you! – Karen (August 2017)

Feedback left on my Facebook page

  • Tom has been an excellent tutor. Really helpful to have and easy to talk to. He helped boost my grade from a B to an A*. Thank You for all your help- Charles (August 2017)

  • Tom has been an exceptional tutor who has supported my daughter in her application to study Medicine. He has been excellent in explaining content whilst maintaining a clear focus on the requirements of the exam board. As a teacher myself, I really appreciate Tom's level of professionalism. He has always been friendly and reliable." - Karen

  • Tom is an excellent tutor, who knows just how to target his teaching so I could get the most out of our sessions. Working at a B grade level, Tom was so helpful in explaining topics to an A grade standard. His style of teaching even the most difficult concepts made them easy to grasp, and his interactive sessions made revising biology that much easier. Thank you Tom!

  • Absolutely brilliant. Very comprehensive teaching which links all areas of the subject to each other making them much easier to understand and remember – Alasdair (August 2017)

  • Absolutely brilliant, always flexible about the topics you want to cover and never ignores the harder parts of the course. I for one went through the Bohr Shift etc about 4 times with Tom until finally it made sense to me. Couldn't have done the exams without him and I'm grateful to have had him as a tutor. – Archie (August 2017)

  • Tom was a really good tutor and took me through the new A Level. Very patient and very reliable and puts in lots of extra effort with the added resources – Grace (August 2017)

  • Tom has been a great help over my final A-level year, tutoring me OCR Biology A. I started the year with low confidence as my AS grades were lower than expected, and I did not always find my teaching at school very clear. Tom explained concepts to me in a much clearer way which really helped me understand difficult topics and finally grasp the fundamentals of Biology and the OCR syllabus. He was always friendly and approachable, making asking questions easy! I would recommend him to anybody. His tutoring allowed me to achieve the grades I needed to study Human Sciences at Exeter Uni this September! – Freya (August 2017)

  • Tom was an exceptional tutor, who went above and beyond to find resources that improved my knowledge and understanding of Biology. I found going through past papers was particularly useful, as Tom was able to explain how the question should be answered. Tom absolutely improved my level of understanding, and resulting grade in Biology. I would recommend Tom to anyone study A-Level Biology and looking for some help. Liam – (August 2017)

How to Answer Hardy-Weinberg Questions - A-level Biology - with question pack

How to understand and answer Hardy-Weinberg Questions - A-level Biology. Remember to look out for questions where they give you a dominant phenotype frequency -for instance Huntingdons disease, where the frequency of the sufferers is 1 in 100000 - therefore q squared (recessive allele phenotype) is 99999 in 100000.

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Haemoglobin Oxygen Dissociation Curve / Bohr Effect Exam Questions - How to understand the Sigmoid Curve

Lots of Haemoglobin Oxygen Dissociation Curve/ Bohr Shift Questions and Markschemes, suitable for OCR A, AQA - and a brief guide to Understanding them.

The key to understanding dissociation curves is firstly to understand the concept of partial pressure and what would make it change. And to understand cooperative binding.

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How to approach and answer A-level Biology Questions that need you to Analyse Figures, Tables and Images - lots of example past paper questions

How to approach and answer A-level Biology Questions that need you to Analyse Figures, Tables and Images - lots of example past paper questions with the markschemes

DO NOT LOOK at the question and then look at the data to answer the question.

  • Look closely at the graph or table

  • look very carefully at the axes - have they plotted mean or rate or time, mass/volume or concentration ?

  • can you see range bars ?

  • In a table what range is in the replicates when you compare to the mean ?

  • what trends can you observe ? then think about what principle of biology is being shown by the the trends.

  • How would you explain the highest value, the lowest value, the point at which the line crosses the x axis, how would you explain the largest range, how would you change the experiment to reduce the spread in the data ?

Once  you have a coherent understanding of the trends  - only then look at the question.

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Nitrogen Cycle - a quick guide to understanding the concept, and a pack of questions - for A-level Biology

How to understand the Nitrogen Cycle

Nitrogen Cycle : A few tips

Start with dead plants and animals or faeces.  

Remember that decomposers are just heterotrophes respiring dead stuff and producing ammonia from the deamination of amino acids (the keto acid that remains following deamination is respired).

Ammonia then gets oxidised to nitrite  and oxidised to nitrate by nitrifying bacteria  - Nitrosomonas and Nitrobacter , both  aerobic chemoautotrophes.

Nitrates are actively transported into the roots, by a carrier protein which uses ATP from the mitochondria, then via the xylem to the leaves. In the leaves the nitrate is reduced to ammonia  and then used to make (with carbon from photosynthesis)  amino acids and nucleic acids  and hence more plant !.

Growing a crop removes protein and nucleotides from a field (and sells it in Tesco !).  To maintain fertility you need to make an input of nitrogen - this can be organic (dead things and faeces), which feed the decomposers. Or inorganic - made by joining nitrogen and hydrogen in the Haber process to make ammonia (applied to fields as ammonium nitrate), lightening also make nitrogen oxides - but is harder to arrange.

Rhizobium, a symbiotic bacteria,  living in root nodules of legumes, benefits from  an anaerobic environment, the legume makes Leghaemoglobin, a protein with a high affinity for oxygen which therefore prevents oxygen from poisoning the nitrogen reducing enzyme of the bacteria.

Rhizobia use sucrose from the plant for respiration. Rhizobia make ammonia (and hence amino acids) from nitrogen gas, the plants use these amino acids for growth. When legumes die, the nitrogen in the  proteins of the dead plant is made available to other non-leguminous plants by decomposers.

Decomposers and nitrifying bacteria are aerobes so ploughing - which increases the availability of oxygen in the soil - will raise the concentration of nitrates and hence the ability of the plants to make more protein.,

Pseudomonas denitrificans is an anaerobe so thrives in waterlogged soil. Denitrification uses nitrate as an electron acceptor, the nitrate is reduced to Nitrogen gas, thus farmers drain fields to maintain fertility of the soil.

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