(b) Explain the events which occur within a female Anopheles mosquito after it has sucked blood from a malaria patient.
The development of Plasmodium in the mosquito’s gut and migration of sporozoites to the salivary glands are key for disease transmission.
- The gametocytes of Plasmodium enter the mosquito’s gut along with the blood meal.
- In the mosquito's stomach:
- The gametocytes develop into gametes.
- The gametes fuse to form zygotes.
- The zygotes develop into sporozoites.
- The sporozoites migrate to the mosquito’s salivary glands.
- The mosquito is now ready to infect another host.

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?