Practise Edexcel A-Level Biology graph skills through trend comments, quantitative graph evidence, tangent-rate calculations, error bars and line equations.
Sickle cell disease is caused by a gene mutation affecting the -globin chain of haemoglobin.
The red blood cells in a person with sickle cell disease are sickle shaped and less elastic. They also have a shorter lifespan than healthy red blood cells.
These sickle shaped red blood cells cannot carry as much oxygen as healthy red blood cells and they get stuck in the capillaries.
The graph shows oxygen dissociation curves for groups of people with sickle cell disease and those without the disease.
The shaded areas represent the range of values for each group of people.
Percentage of haemoglobin saturated with oxygen (\%)
A p50 value is the partial pressure of oxygen that results in 50\% saturation of haemoglobin.
Calculate the largest difference in the p50 values between a person with sickle cell disease and a person without this disease.
Give your answer to an appropriate number of decimal places.
Statins are used in the prevention and treatment of cardiovascular disease (CVD). Red yeast rice (RYR) is a source of food and medicine in Asia. It is produced by the fermentation of rice by yeast. Red yeast rice contains monacolin K, which is similar to a statin.
The graph shows the production of monacolin K during the fermentation of rice by yeast. Concentration of monacolin K / mg per 100 g of rice
Calculate the mean rate of production of monacolin K in this culture, in the 45-day time period. Give your answer to two decimal places. Answer mg per 100 g of rice per day
The enzyme invertase breaks down sucrose into its two component monosaccharides.
Suggest how the initial rate of this reaction could be determined.