1. 1
   A gardener finds a garden snail on a lettuce leaf. Over the next hour, she watches it glide slowly across the leaf, extend its eye stalks when she moves her hand close to it, and leave behind a trail of mucus.

   (a)

   The snail extends its eye stalks and pulls them back in when the gardener's hand moves close to it. Which characteristic of living organisms does this behaviour demonstrate?

   [1 mark]

   • ASensitivity
   • BExcretion
   • CNutrition
   • DRespiration

   (b)

   Which of the following best defines the characteristic of movement in living organisms?

   [1 mark]

   • AA permanent increase in size and dry mass
   • BAn action, by part or all of an organism, causing a change of position
   • CDetecting and responding to changes in the surroundings
   • DThe production of new individuals of the same kind

   (c)

   Later, the gardener finds a cluster of small white eggs the snail has laid under a leaf, and notices the snail itself has grown noticeably larger than it was a month ago. State which two characteristics of living organisms these two observations show, and define each one.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A field researcher records the scientific names of two closely related tree species growing in a nature reserve: Quercus robur (English oak) and Quercus rubra (red oak). The two species do not normally interbreed with each other in the wild.

   (a)

   In the scientific name Quercus robur, what does the first part of the name (Quercus) show?

   [1 mark]

   • AThe species
   • BThe kingdom
   • CThe genus
   • DThe common name

   (b)

   Which statement best defines a species?

   [1 mark]

   • AA group of organisms with the same first (genus) name only
   • BA group of organisms found in the same habitat
   • CA group of organisms sharing a common ancestor with all other organisms
   • DA group of organisms that can reproduce to produce fertile offspring

   (c)

   Explain why Quercus robur and Quercus rubra are classified as two different species, even though they belong to the same genus.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A microbiologist is given three unidentified samples to place into kingdoms. Sample 1 is single-celled, has a nucleus, and was found living freely in pond water. Sample 2 is single-celled, has no nucleus, a cell wall and circular DNA, and was found in a soil sample. Sample 3 is many-celled, made of thread-like hyphae with a cell wall made of chitin, and absorbs nutrients from a piece of decaying wood.

   (a)

   State which kingdom each of Sample 1, Sample 2 and Sample 3 belongs to.

   [3 marks]

   (b)

   Explain, using features of their cells, how you could distinguish between the fungus sample (Sample 3) and a many-celled green plant sample, if both had a cell wall.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A student is comparing three organisms found in a garden pond: duckweed (a small flowering plant floating on the surface), a whirligig beetle swimming on the surface, and a colony of bacteria growing on a submerged stone. She wants to classify each organism and explain how classification systems reflect evolutionary relationships.

   (a)

   Explain how the duckweed and the whirligig beetle would each be classified, in terms of which kingdom they belong to and which group within that kingdom, giving the features that justify each classification.

   [6 marks]

   (b)

   The bacterial colony found on the stone cannot easily be classified using visible features alone. Explain how scientists use DNA base sequences to help classify organisms like this, and explain why classification systems are considered to reflect evolutionary relationships.

   [6 marks]

   Total for question 4: 12 marks

5. 5
   A marine biologist studying a coral reef notices that a sea anemone, when touched, quickly withdraws its tentacles into its body. Weeks later, she finds the same anemone has produced dozens of tiny offspring anemones nearby.

   (a)

   The sea anemone withdrawing its tentacles when touched is an example of which characteristic of living organisms?

   [1 mark]

   • ASensitivity
   • BGrowth
   • CExcretion
   • DNutrition

   (b)

   The anemone producing dozens of tiny offspring anemones is an example of which characteristic of living organisms?

   [1 mark]

   • AExcretion
   • BReproduction
   • CGrowth
   • DMovement

   (c)

   The anemone was also observed taking in small pieces of food using its tentacles, and its body increased steadily in size and dry mass over several months. Identify and briefly define the two characteristics of living organisms shown by these two additional observations.

   [2 marks]

   Total for question 5: 4 marks

6. 6
   Researchers compare short DNA base sequences from four species of frog living in the same rainforest. Species P and Q have DNA base sequences that are almost identical, species R has a moderately similar sequence to P and Q, and species S has a very different sequence from all the others.

   (a)

   Based on this evidence, which two frog species most likely share the most recent common ancestor?

   [1 mark]

   • AP and S
   • BQ and R
   • CP and Q
   • DR and S

   (b)

   What does the base sequence of species S being very different from the others suggest?

   [1 mark]

   • ASpecies S reproduces asexually
   • BSpecies S is not a real species
   • CSpecies S has the same genus name as the others
   • DSpecies S shares only a more distant common ancestor with the others

   (c)

   Explain what the DNA base sequence evidence in this example suggests about the evolutionary relationships between the four species of frog.

   [2 marks]

   Total for question 6: 4 marks

7. 7
   An ecologist collects four small invertebrates from leaf litter. Animal 1 has a body divided into head, thorax and abdomen, three pairs of jointed legs and one pair of antennae. Animal 2 has eight jointed legs and no antennae. Animal 3 has a long, segmented body with one pair of jointed legs on each segment. Animal 4 has a hard shell, two pairs of antennae and jointed legs, and was found under a damp log near the pond edge.

   (a)

   Name the arthropod group to which each of Animal 1, Animal 2 and Animal 3 belongs.

   [3 marks]

   (b)

   Identify the arthropod group to which Animal 4 belongs, and explain, using features described above, how you can tell that all four animals belong to the arthropod group rather than to the vertebrate groups.

   [4 marks]

   Total for question 7: 7 marks

8. 8
   A student examines three unfamiliar organisms sent from a biology field trip. Organism X is many-celled, its cells have no cell wall and no chloroplasts, it moves around using four jointed legs and responds quickly when touched. Organism Y is many-celled, its cells have cellulose cell walls, chloroplasts and a permanent vacuole, and it does not move from place to place. Organism Z is single-celled, has no nucleus, a cell wall and circular DNA, and was found in a soil sample.

   (a)

   For each of Organism X, Organism Y and Organism Z, state which kingdom it belongs to and explain, using features of its cells, why it is placed in that kingdom.

   [6 marks]

   (b)

   Organism X shows several characteristics of living organisms. Describe three of these characteristics that Organism X, as a typical animal, would show, and explain how classifying organisms like X, Y and Z into kingdoms and smaller groups is useful to biologists.

   [6 marks]

   Total for question 8: 12 marks

End of questions