Washing powders often contain different types of enzymes that break down substances in stains. An investigation was carried out into washing powder that contained enzymes and washing powder that did not contain enzymes. The graph below shows the results of this investigation.
Some of the substances that cause food stains are large insoluble proteins.
Explain how washing powder containing enzymes would be able to remove these stains.
The manufacturers of the washing powder containing enzymes claimed that their washing powder was more effective at removing tough stains compared to the washing powder without enzymes.
Based on the results of the investigation in part a), evaluate the claim of the manufacturers.
Coeliac disease is an autoimmune disorder that occurs in some people when they consume gluten, a type of protein found in certain grains. During an autoimmune disorder the immune system launches an attack on healthy body tissue which involves lymphocytes.
The following diagram compares the lining of the small intestine of a healthy person and a person suffering from coeliac disease.
Based on the information provided, explain how coeliac disease will affect the absorption of nutrients.
People suffering from stomach cancer can undergo surgery to remove a part of their stomach. This type of surgery is known as a gastrectomy and can result in the patient developing a set of symptoms known as 'dumping syndrome'.
Usually the stomach will slowly release small amounts of partially digested food into the small intestine over a period of several hours, but in patients suffering from dumping syndrome large amounts of poorly digested food are released into the small intestine in a short period of time after a meal. This poorly digested food tends to be high in dissolved nutrients such as sugars.
i)
One symptom of dumping syndrome is a large volume of fluid in the small intestine.
Explain why this is the case.
[2 marks]
ii)
Suggest one possible symptom that might result from this excess of fluid.
Up to a third of dumping syndrome patients suffer from a form of the condition known as late dumping syndrome. These patients will experience symptoms 1-3 hours after eating due to the effects of the hormone insulin.
Suggest why these symptoms would arise 1-3 hours after eating.
