There are seven mandatory labs that students are expected to complete, I refer to them as 6+1 as six fall within the Standard course and one within the Higher level course (its perfectly acceptable to include the HL lab within the PSOW of the SL course). Understandings of these labs / practicals will be examined in Paper 3. This is a significant change to the new course. It also follows that students should incorporate the labs in some way as part of their notes for examination review
Practical 1 Use of a light microscope to investigate the structure and ultra structure of cells and tissues, with drawing of cells and calculation of the magnification of drawings and the actual size of structures shown in drawings or micrographs.
Practical 2 Estimation of osmolarity in tissues by bathing samples in hypotonic and hypertonic solutions.
Practical 3 Experimental investigation of a factor affecting enzyme activity
Practical 4 Separation of photosynthetic pigments by chromatograph.
- If you use 9 parts lighter fluid or BBQ fire starter to 1 part acetone it should work.
- Use small test tubes with thin strips of paper to minimize the amount of solvent you use.
- Recycle the solvent for later use.
Practical 5 Setting up sealed mesocosms to try to establish sustainability
the two key concepts here include
- A mesocosm as a model of a larger ecosystem
- A closed ecosystem, one in which energy enters and leaves but matter does not
Practical 6 Monitoring of ventilation in humans at rest and after mild and vigorous exercise
- ” * All participants in research activities must be informed before commencing the research that they have the right to withdraw at any time. Pressure must not be placed on any individual participant to continue with the investigation beyond this point. * Each participant must be informed of the aims and objectives of the research and in addition be shown the results of the research. * Informed consent should be obtained from the people who are the subject of the fieldwork. Research involving children needs the written consent of parent(s) or guardian(s). Students must ensure that parents are fully informed about the implications for children who take part in such research. Where research is conducted with children in a school, the written consent of the teachers concerned must also be obtained.”
Adding consent forms to the report or essay would be in conflict with the demand that data must be anonymous. Authors (or schools) must keep the signed forms and mention in the text that the procedure was followed as prescribed.
Practical 7 Measurement of transpiration rates using potometers
In my next blog I will focus on mesocosms