Answer 1

Question 1

State and explain two benefits to the mosquitoes when they move away from the pond.

Answer:


Since they are more spread out, they are able to look for more as there is less with other mosquitoes. Since they are able to travel greater , there is a higher chance of finding in order to .


Question 2

Ace researched more about reducing the spread of Dengue fever. One method is to kill mosquito larva living in the water before they grow into adult mosquitoes and are able to fly away. To do so, he poured some oil into the pond such that there is a thin layer of oil on the water surface. Explain why Ace did so.

Answer:

The oil will the of the mosquito larvae. Thus they cannot take in (oxygen) from above the surface of the water and will die.



Helping Keywords: [competition] [reproduce] [mates] [distance] [food] [breathing tubes] [atmospheric air] [block]



RECAP THE CONCEPTS

Mammals

  • have an outer body covering of hair / fur.

  • produce milk to feed their young.

  • breathe atmospheric air using their lungs.

Birds

  • have an outer body covering of feathers.

  • have a beak, a pair of wings and a pair of legs.

  • reproduce by laying eggs.

Fish

  • use gills to breathe, taking in dissolved oxygen from the water.

  • have an outer body covering of scales.

  • most reproduce by laying eggs.

Insects

  • have 6 legs.

  • have 3 body parts: head (with feelers), thorax and abdomen.

  • have a hard outer covering called the exoskeleton
    They moult in order to grow larger.

Reptiles

  • have dry skin covered with scales.

  • breathe using lungs.

  • reproduce by laying eggs that have a leathery shell.

Amphibians

  • lay eggs in water; young live in water.


  • the young of amphibians take in dissolved oxygen from the water using gills.


  • adult amphibians live on land and can breathe atmospheric air using both moist skin and lungs.
    They can also take in dissolved oxygen in the water through the moist skin.