Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
A mosquito undergoes a process called complete metamorphosis, which consists of distinct stages: Egg, Larva, Pupa, and Adult.
Mosquitoes are known as 'vectors' because they carry disease-causing microorganisms (pathogens) from an infected person to a healthy person. For example, the female Anopheles mosquito carries the parasite which causes Malaria.
The first three stages of the mosquito life cycle—Egg, Larva, and Pupa—take place in stagnant (water). This is why preventing water stagnation is the most effective way to control mosquito populations.
The Larva stage is also called a 'wriggler'. It feeds on organic matter in the water and breathes through a tube at the water's surface, requiring a constant supply of .
The Pupa stage is a non-feeding stage, often called a 'tumbler'. This is where the mosquito transforms into an adult.
Disease control methods include using mosquito nets, wearing long-sleeved clothes, and using biological controls like fish that eat mosquito larvae.
📐Formulae
💡Examples
Problem 1:
Why is it recommended to pour a layer of kerosene or oil over stagnant pools of to prevent the spread of diseases like Malaria?
Solution:
Pouring oil creates a thin film on the surface of the , which cuts off the supply of atmospheric to the mosquito larvae and pupae.
Explanation:
Since mosquito larvae breathe oxygen from the air through respiratory tubes, the oil layer acts as a barrier. Without , the larvae cannot survive and die before reaching the adult stage.
Problem 2:
Identify the vector and the causative agent for the disease Malaria.
Solution:
Vector: Female Anopheles Mosquito; Causative Agent: (a protozoan parasite).
Explanation:
The mosquito itself does not cause the disease; it acts as a carrier (vector) that transfers the parasite into the human bloodstream during a bite.