Question 1: Define the term 'haemoglobin' and explain its role in blood.

Answer: Haemoglobin is a protein found in red blood cells that binds to oxygen, allowing it to be transported from the lungs to body tissues.

Question 2: Describe the primary function of white blood cells in the blood.

Answer: White blood cells are part of the immune system and help defend the body against infections.

Question 3: What is the main component of plasma, and what is its approximate percentage in blood?

Answer: The main component of plasma is water, making up about 55% of blood volume.

Question 4: Calculate the volume of plasma in 5 litres of blood, given that plasma constitutes approximately 55% of blood volume.

Answer: Volume of plasma = 5 litres x 0.55 = 2.75 litres

Question 5: Identify two safety precautions that should be observed when handling blood samples in a laboratory setting.

Answer: Wearing gloves and using sterilised equipment to prevent infection transmission.

Question 6: In an experiment, it was found that a blood sample contains 45% red blood cells, 5% white blood cells, and 50% plasma. Explain how the relative proportions of these components contribute to their functions.

Answer: The high proportion of red blood cells (45%) ensures efficient oxygen transport via haemoglobin. White blood cells (5%) are fewer but vital for immune responses. Plasma (50%) acts as a medium for transporting nutrients, hormones, and waste products, supporting overall blood function.

Question 7: Explain why maintaining a proper balance of blood components is important for health.

Answer: An imbalance can impair oxygen delivery, weaken immune responses, or cause conditions like anaemia or blood clots, thus maintaining balance is vital for overall health.

Question 8: A blood sample shows a higher than normal percentage of white blood cells. What could be the potential causes?

Answer: Possible causes include infection, inflammation, or a blood disorder such as leukaemia.

Question 9: Describe a simple experiment to compare the volume of red blood cells in two blood samples.

Answer: Use a haematocrit test by filling capillary tubes with blood, centrifuging them to separate components, and measuring the proportion of red blood cells in each sample to compare their volumes.

Question 10: Discuss how advances in biotechnology could improve the treatment of blood disorders.

Answer: Biotechnology can enable production of artificial blood substitutes, gene therapy to correct genetic blood disorders like sickle cell disease, and develop personalised medicine based on genetic profiling, improving treatment effectiveness and safety.