Question 1: Blood is a vital fluid in the human body composed of various components that perform essential functions. The main components are red blood cells, white blood cells, platelets, and plasma. Understanding the proportion and function of each component helps in diagnosing various health conditions.

Answer: Blood consists mainly of plasma, red blood cells, white blood cells, and platelets, each with specific functions such as oxygen transport, immune response, and clotting.

Question 1: Define plasma and describe its primary role in blood.

Answer: Plasma is the liquid part of blood that transports nutrients, hormones, and waste products; it also helps maintain blood pressure and volume.

Question 2: Explain the main function of red blood cells in the circulatory system.

Answer: Red blood cells transport oxygen from the lungs to the body tissues and return carbon dioxide to the lungs for exhalation.

Question 1: Calculate the approximate number of red blood cells in a 5-litre adult human blood sample, given that the average concentration is 5 million cells per microlitre.

Answer: 25 x 10^12 cells

Question 2: If a person has a white blood cell count of 7,000 cells per microlitre of blood, what is the total number of white blood cells in their 4.5 litre blood volume?

Answer: Approximately 2.8 x 10^11 cells

Question 1: Design a simple experiment to compare the red blood cell counts of two different blood samples. Identify the variables involved and suggest safety precautions for handling blood samples (theory only).

Answer: Students should set the independent variable as the source of blood (e.g., different individuals), the dependent variable as the red blood cell count, and control variables such as temperature, pH, and anticoagulant use. Safety precautions include wearing gloves, avoiding direct contact with blood, and disposing of samples properly.

Question 1: A study reports that in a sample of 100 individuals, the average haemoglobin level is 13.5 g/dL with a standard deviation of 1.2 g/dL. Explain what this information indicates about the blood quality of the population sample.

Answer: This indicates that most individuals have haemoglobin levels close to 13.5 g/dL, with some variation. The standard deviation shows the spread of the data, suggesting that the majority of the population's haemoglobin levels are within a range of approximately 12.3 to 14.7 g/dL, reflecting generally healthy blood oxygen-carrying capacity.

Question 1: Describe how blood tests measuring white blood cell counts can help in diagnosing infections or immune disorders.

Answer: Blood tests can detect abnormal white blood cell levels, indicating infections, immune deficiencies, or disorders such as leukemia, aiding in diagnosis and treatment planning.

Question 2: A new technology claims to measure blood viscosity rapidly. Explain why understanding blood viscosity is important in medical diagnosis.

Answer: Blood viscosity affects how easily blood flows through vessels. Abnormal viscosity can indicate conditions like dehydration, polycythemia, or blood clotting disorders, which may lead to cardiovascular problems. Rapid measurement aids in timely diagnosis and treatment.