Classification of organismsIB MYP Biology: Subtopic test

1. 1
   A biologist in Santiago sorts the organisms she has collected from a pond and its banks into the five kingdoms. Her collection includes a mushroom growing on a rotting log, a bacterium from the pond water, a water lily, a pond snail and an amoeba.

   (a)

   A multicellular organism has cell walls and no chloroplasts, and it feeds on dead material using thread-like hyphae. In which kingdom is it classified?

   [1 mark]

   • APlants
   • BFungi
   • CProtists
   • DAnimals

   (b)

   Which kingdom contains organisms whose cells have no nucleus?

   [1 mark]

   • AProkaryotes
   • BProtists
   • CFungi
   • DPlants

   (c)

   Outline two differences between plants and animals.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A zoo in Singapore is preparing information boards for four of its animals: a crocodile, a frog, a penguin and a fruit bat. The zoo wants to show visitors which vertebrate group each animal belongs to.

   (a)

   Which feature is found only in mammals?

   [1 mark]

   • AThey lay eggs
   • BThey have a backbone
   • CThey have scales
   • DThey feed their young on milk from mammary glands

   (b)

   An animal has dry scaly skin and lays soft-shelled eggs on land. Which group does it belong to?

   [1 mark]

   • AAmphibians
   • BFish
   • CReptiles
   • DBirds

   (c)

   Explain why the fruit bat is classified as a mammal and not as a bird, although it can fly.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   An entomologist in Kuala Lumpur sorts invertebrates collected from a rainforest. Among them are a beetle, which has six legs and a body in three parts, a spider, which has eight legs and a body in two parts, a crab and a centipede. All four belong to the same large group of invertebrates.

   (a)

   State three features that all arthropods have.

   [3 marks]

   (b)

   Explain how the entomologist can show that the beetle is an insect but the spider is an arachnid.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   Researchers in Costa Rica are surveying a rainforest reserve. They have found four species of beetle and need a way for volunteers to identify them. Beetle 1 has wings and stripes on its back. Beetle 2 has wings and no stripes. Beetle 3 has no wings and long antennae. Beetle 4 has no wings and short antennae. The government is considering paying for a full survey to identify and classify every species in the reserve.

   (a)

   Construct a dichotomous key that identifies the four beetles, and explain why scientists give each species a binomial name.

   [6 marks]

   (b)

   Discuss the benefits and drawbacks of paying for a full survey of every species in the reserve, and justify whether the government should do so.

   [6 marks]

   Total for question 4: 12 marks

End of questions