1. 1
   A field guide lists an organism with the scientific name Panthera leo, and describes it as able to interbreed with other Panthera leo individuals to produce fertile offspring.

   (a)

   In the binomial system of naming, what does the first part of this name, Panthera, represent?

   [1 mark]

   • AThe species
   • BThe genus
   • CThe kingdom
   • DThe family

   (b)

   The field guide states that Panthera leo individuals can interbreed with each other to produce fertile offspring. Which term describes a group of organisms defined in this way?

   [1 mark]

   • AA kingdom
   • BA phylum
   • CA species
   • DA genus

   (c)

   Explain why using the scientific binomial name Panthera leo is more useful for scientists worldwide than using the common name "lion".

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A student is constructing a dichotomous key to identify four types of leaves collected from a garden, based on features such as leaf edge and leaf shape.

   (a)

   What is the main purpose of a dichotomous key?

   [1 mark]

   • ATo identify an organism by working through a series of paired statements
   • BTo show the evolutionary history of a group of organisms
   • CTo compare the DNA base sequences of different organisms
   • DTo measure the size of specimens using magnification

   (b)

   At each stage of the student's dichotomous key, a leaf is compared against a pair of statements, such as "leaf edge smooth" or "leaf edge toothed". What feature must each pair of statements have for the key to work correctly?

   [1 mark]

   • AThey must both be true for every leaf
   • BThey must be based on the leaf's evolutionary ancestry
   • CThey must describe the leaf's DNA sequence
   • DThey must be mutually exclusive, so only one applies to each leaf

   (c)

   State two identifiable features, other than leaf edge, that the student could use to construct pairs of statements in her dichotomous key for the leaves.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   Scientists comparing the DNA of four bird species find that species W and X have almost identical base sequences, while species Y and Z have base sequences that are quite different from W, X and each other.

   (a)

   State what is meant by the five-kingdom classification system, and name the kingdom into which all four bird species would be placed.

   [3 marks]

   (b)

   Explain what the similarity in DNA base sequences between species W and X suggests about their evolutionary relationship, compared with the relationship between W and Y.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A museum exhibit displays a lion (a mammal), an eagle (a bird), a crocodile (a reptile), a frog (an amphibian) and a shark (a fish) as vertebrates, and separately displays a millipede, a beetle, a spider and a crab as arthropods.

   (a)

   Explain the main features used to place organisms into these vertebrate groups within the animal kingdom.

   [6 marks]

   (b)

   Explain the main features used to place the millipede, beetle, spider and crab into their respective groups within the arthropods, and state one feature shared by all arthropods.

   [6 marks]

   Total for question 4: 12 marks

End of questions