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Cholesterol, diet and energy budgetsEdexcel A-Level Biology A: Flashcards

What these 14 flashcards ask

  • What does LDL do?
  • What does HDL do?
  • Why is cholesterol carried in lipoproteins?
  • Why does a correlation between cholesterol and CVD not prove causation?
  • Name two pieces of evidence that LDL cholesterol causes CVD.
  • Write the formula for BMI.
  • What BMI range is regarded as obese?
  • How is waist-to-hip ratio calculated?
  • Why can WHR be more informative than BMI?
  • How does smoking increase the risk of CHD?
  • What happens when energy intake exceeds expenditure?
  • State two health risks of obesity.
  • What colour change shows vitamin C in the DCPIP test?
  • Why is a calibration with known ascorbic acid concentration needed?

Exam questions on Cholesterol, diet and energy budgets

  1. A 52-year-old man has a routine health check. His total blood cholesterol is 6.4 mmol dm⁻³, his LDL cholesterol is 4.6 mmol dm⁻³ and his HDL cholesterol is 0.8 mmol dm⁻³. His doctor tells him that his lipoprotein profile puts him at increased risk of cardiovascular disease (CVD).
    Explain why a high ratio of HDL to LDL in the blood is associated with a lower risk of CVD.2 marks
  2. A 45-year-old woman is 1.64 m tall and has a body mass of 82 kg. Her waist measures 98 cm and her hips measure 102 cm. A health adviser uses her measurements to assess her risk of coronary heart disease (CHD). For women, a waist-to-hip ratio above 0.85 is regarded as indicating raised risk.
    Suggest why waist-to-hip ratio can give more useful information about the risk of CHD than BMI alone.2 marks
  3. A man's energy intake from food averages 11 500 kJ per day. His total daily energy expenditure (basal metabolism plus activity) averages 9 800 kJ per day. Assume that any surplus energy is stored as body fat and that 1.0 kg of body fat stores 37 000 kJ.
    Calculate the mass of body fat the man would gain in 30 days. Show your working.3 marks
See the full worksheet

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).