Biology Miss Shipton, Ms Lee, Mrs Campbell, Mrs Dukes

What will I study? There are 8 key topic areas, 4 in each year of study with 12 practicals you must have carried out.

Practical endorsement and subject assessment At Y1 you will sit 2 examinations on theory and practical content. For the full A level you sit 3 examinations on theory and practical content. The third exam is synoptic and will include an extended essay. There will be 12 assessed practicals throughout the full course, 6 in each year. There is also the opportunity for field work in Y13.

Pre-Course Reading and summer work (see reading list) If you have done triple science you will need to keep your revision guides and GCSE books and re-familiarise yourself with certain areas over the summer: For those who have done double award, there are many areas that you will have covered plus some that are in the triple only which means that you will need to familiarise yourself with those as well. This may mean getting a GCSE Biology triple revision guide, or find a friend who did triple that is not continuing with sciences. We recommend the Headstart to A level Biology guide. Your Maths skills also need to be up to date. CGP have a Maths skills for Biologists guide and an A level Biology revision guide which we recommend.

Diagnostic assignment The Diagnostic assignment is a paper put together to test the areas that come up at AS that you should be familiar with from GCSE as well as data handling to finish from todays practical session. Topics will include: Enzymes Cell structure Immunity and defence Osmosis (triple content) Gas exchange (double plus extra in triple content) Heart rate data

Todays activity: Dilution series practical This is a skill you can be examined on and ties in to the one of the first topics you study: Biological molecules. Follow your instruction sheet carefully making notes as you go if you wish. Collect your data and then you can start on the secondary practical skill sheet. At the end of the session remember to collect graph paper as well as the diagnostic assignment.

Working out a dilution series: checking your Maths skills Sugar solution provided concentration – 1M Concentration of sugar solution (M) Volume of 1M sugar solution (cm 3 ) Volume of distilled water (cm 3 ) Total volume required (cm 3 )

Working out a dilution series Example - Sugar solution provided has a concentration of 1M. You want 20cm 3 of a solution with a concentration of 0.1M Volume of sugar solution needed = Concentration of sugar solution wanted Concentration of sugar solution provided x Total volume required The remainder of the total volume required is made up with water.

Volume of sugar solution needed = x 20 Volume of water required = 18cm 3 = 2cm 3 Example - Sugar solution provided has a concentration of 1M. You want 20cm 3 of a solution with a concentration of 0.1M

Producing a dilution series The technician has only made up 1 molar solution. How can we produce 20ml of the five solutions we need using this solution and distilled water? Concentration of sugar solution (mol) Volume of 1 mol sugar solution (ml) Volume of distilled water (ml) Total volume (ml)

Alternative method: Dilution series practical (25mins) 1.Set up a serial dilution stating with a 1% glucose solution. To do this label six test tubes 1-6 with a marker pen and place 2cm 3 1% glucose solution in the first tube and 2 cm 3 distilled water in each of the other five. Now add 2cm 3 1% glucose solution to tube 2 and mix thoroughly before transferring 2 cm 3 of this solution to tube 3. Work along the tubes, each time mixing the content thoroughly before transferring 2 cm 3 to the next tube, until you reach tube 6. Mix the contents of tube 6 and then discard 2 cm 3. Add 2 cm 3 Benedict’s solution to each tube and again mix thoroughly. 2.Place all tubes in a boiling water bath and leave them for a standard time (at least 3 minutes). 3.Remove and arrange the tubes in order, recording the colour against the concentration. This is the reducing sugars test.