Science Form 2

• Malaysia is one of the 12 megabiodiversity countries in the world.
• Biodiversity


  The diversity of organisms, whether microorganisms, animals or plants
• Biodiversity exists as a result of diversity of habitat and climate.
• Importance of biodiversity

  • Sources of food
  • Balance in nature
  • Recreational places
  • Medical
  • Raw materials for industries
  • Education
• Deforestation activities cause animals to lose their habitat and food sources.
• Methods to maintain and conserve biodiversity

  • Banning the killing or trade of endemic and endangered animals and plants
  • Protecting the habitat through creating national parks, marine parks, forest reserves and wildlife sanctuaries
  • Undertaking reproductive programmes such as seedling nurseries to help with reforestation and turtle hatcheries
• Endemic species


  A species that lives in clusters within a restricted habitat in a specific location
• Classification of animals


  • Invertebrates
  • Vertebrates
• Classification of invertebrates


  • Without legs
  • With legs
  • Without segmented body
  • With segmented body
  • Three pairs of legs
  • More than three pairs of legs
• The two main groups of organisms are animals and plants
• Invertebrates


  Animals without a backbone
• Vertebrates


  Animals with a backbone
• Invertebrates without legs and without segmented bodies

  • Sponge
  • Sea anemone
  • Corals
  • Planaria
  • Snail
• Invertebrates without legs with segmented bodies

  • Tapeworm
  • Earthworm
  • Leech
• Invertebrates with legs


  • Insects are the largest group of animals with 950,000 species
  • Have segmented bodies
  • Have hard outer shells (exoskeleton)
  • Three pairs of legs
  • More than three pairs of legs
• Vertebrates

  • Fish
  • Amphibians
  • Reptiles
  • Birds
  • Mammals
• Fish


  • Poikilothermic
  • Covered in hard and slimy scales
  • Have fins and a tail
  • Breathe through gills
  • Lay eggs
  • Undergo external fertilisation
• Amphibians


  • Poikilothermic
  • Live on land and in water
  • Covered with moist skin
  • Young amphibians breathe through gills
  • Adult amphibians breathe using their lungs and moist skin
  • Produce jelly-like eggs (spawn) without a shell
  • Undergo external fertilisation
• Reptiles


  • Poikilothermic
  • Produce eggs with a shell
  • Breathe through lungs
  • Have scales and hard skin
  • Undergo internal fertilisation
• Birds


  • Homeothermic
  • Covered with feathers to maintain body temperature
  • Breathe through lungs
  • Have wings that help some birds to fly
  • Have a pair of scaly feet
  • Undergo internal fertilisation
  • Produce eggs with hard shell
• Mammals


  • Homeothermic
  • Covered with fur or hair
  • Breathe through lungs
  • Undergo internal fertilisation
  • Give birth and nurse their young
• Plants


  • Non-flowering plants
  • Flowering plants
• Non-flowering plants


  • Moss
  • Fern
  • Conifer
• Moss


  • Reproduce by producing spores
  • Non-vascular
• Fern


  • Reproduce by producing spores
  • Vascular
• Conifer


  • Reproduce by bearing cones
  • Vascular
• Flowering plants


  • Produce flowers which become fruits that contain seeds
  • Each seed has a cotyledon, which is stored food that is used by the seed to germinate
• Differences between monocotyledons and dicotyledons

  • Number of cotyledons
  • Root
  • Leaf
  • Stem
  • Example
• Monocotyledon


  Flowering plant with one cotyledon
• Dicotyledon


  Flowering plant with a pair of cotyledons
• Producers


  Organisms that produce their own food through photosynthesis
• Consumers


  Organisms that eat other organisms
• Decomposers


  Organisms that break down dead animals and plants into simpler materials or nutrients
• Primary consumer


  Herbivores and omnivores that eat producers
• Secondary consumer


  Omnivores and carnivores that eat primary consumers
• Tertiary consumer


  Secondary carnivores that eat secondary consumers
• Decomposers


  • Mushrooms
  • Mould
  • E.coli bacteria
• Food chain


  Shows the feeding relationship between organisms
• Food web


  Interconnection of a few food chains
• Energy is transferred from one organism to another in a food web