Question 1: Define malaria and specify the organism responsible for causing it.

Answer: Malaria is a disease caused by Plasmodium parasites, transmitted to humans through the bites of infected female Anopheles mosquitoes.

Question 2: Describe the lifecycle of Plasmodium within the human host.

Answer: The lifecycle begins when an infected mosquito bites a human, injecting sporozoites into the bloodstream. These migrate to the liver, where they develop into merozoites. Merozoites then invade red blood cells, multiply, and cause symptoms. Some develop into gametocytes, which are taken up by a mosquito during a blood meal, continuing the cycle.

Question 3: Explain how malaria is transmitted from one person to another.

Answer: Malaria is transmitted through the bite of an infected female Anopheles mosquito, which injects Plasmodium parasites into the bloodstream of humans.

Question 1: If a mosquito bites 10 people per night and 2% of mosquitoes are infected with Plasmodium, how many infected mosquitoes would bite 50 people in one night? Show your calculation.

Answer: Number of infected mosquitoes = (10 mosquitoes per person * 50 people) * 2% = 500 * 0.02 = 10 infected mosquitoes.

Question 2: A study shows that in a certain area, 80% of diagnosed malaria cases are confirmed through blood tests. If 150 people show symptoms, how many are likely to be confirmed cases? Show your work.

Answer: Confirmed cases = 80% of 150 = 0.80 * 150 = 120 cases.

Question 3: In a village, 200 people are at risk of malaria. If a control program reduces the mosquito population by 60%, what impact does this have on the risk level assuming the initial risk was proportional to the mosquito population?

Answer: Reducing the mosquito population by 60% decreases the risk of malaria transmission proportionally, lowering the risk level to 40% of the original.

Question 1: Design a simple experiment to test the effectiveness of a new mosquito net treatment in reducing malaria transmission. Describe the variables involved and safety precautions.

Answer: The experiment involves two groups: one using treated mosquito nets and one using untreated nets. The independent variable is whether the net is treated or not. The dependent variable is the number of malaria cases in each group over a specified period. Control variables include mosquito population, exposure time, and environment. Safety precautions include wearing protective clothing, handling chemicals carefully, and ensuring proper disposal of any substances used.

Question 2: Identify two variables that would affect the outcome of a test measuring the effectiveness of mosquito repellents in preventing bites.

Answer: Variables include the concentration of the repellent and the duration of its effectiveness.

Question 3: Explain why it is important to include a control group in experiments testing malaria prevention methods.

Answer: A control group allows comparison to determine the actual effect of the intervention, ensuring that results are due to the treatment and not other factors.

Question 1: A region reports a 50% decrease in malaria cases after introducing insecticide-treated bed nets. What are possible reasons for this decline?

Answer: Possible reasons include reduced mosquito bites due to the nets, decreased mosquito populations, and improved community awareness and preventive measures.

Question 2: Discuss how advances in genetic engineering could contribute to malaria control in the future.

Answer: Genetic engineering can produce genetically modified mosquitoes that are unable to carry or transmit Plasmodium, reducing transmission. It can also involve modifying mosquito populations to decrease their lifespan or reproductive capacity, thereby lowering the spread of malaria.

Question 3: Identify and explain one challenge associated with eradicating malaria using current control strategies.

Answer: One challenge is insecticide resistance, where mosquitoes evolve to survive insecticide treatments, making control measures less effective.