Sexual and asexual reproductionIB MYP Biology: Subtopic test

1. 1
   A gardener in the Netherlands grows strawberries. One plant sends out long stems that grow along the soil surface. A new small plant grows at intervals along each stem, and the gardener cuts these new plants off and plants them in new beds.

   (a)

   What are the long stems that grow along the soil surface called?

   [1 mark]

   • ARunners
   • BPollen tubes
   • CSpores
   • DRoots

   (b)

   How do the new plants compare genetically with the parent plant?

   [1 mark]

   • ADifferent, because they come from two parents
   • BIdentical, because they are produced by asexual reproduction
   • CDifferent, because gametes fuse during fertilisation
   • DHalf the genes of the parent, because they grow from a single stem

   (c)

   Suggest two advantages to the gardener of growing new plants from runners rather than from seeds.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   In an orchard in New Zealand, bees visit apple blossom to collect nectar. Later in the season the apples ripen. Birds and people eat some of the apples and drop the seeds some distance from the tree.

   (a)

   What is the name for the transfer of pollen from the anther to the stigma, which the bees carry out?

   [1 mark]

   • AFertilisation
   • BGermination
   • CPollination
   • DSeed dispersal

   (b)

   What happens during fertilisation in a flowering plant?

   [1 mark]

   • APollen lands on the stigma
   • BA seed is carried away from the parent plant
   • CThe fruit ripens
   • DA male gamete from the pollen fuses with a female gamete in the ovule

   (c)

   Explain why it is an advantage to the apple tree that its seeds are dropped away from it.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A student compares how far a fan can carry three types of seed. She drops each seed from the same height in front of a table fan on its lowest setting and measures how far from the starting point it lands. She uses five seeds of each type. The mean distance is 3.2 m for sycamore seeds, which have a wing, 4.5 m for dandelion seeds, which have a ring of fine hairs, and 0.4 m for pea seeds, which are smooth and heavy.

   (a)

   Identify the independent variable, the dependent variable and one control variable in this investigation.

   [3 marks]

   (b)

   Explain how the structure of the seeds accounts for the results, and why wind dispersal helps the parent plant.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A cooperative of banana farmers in Ecuador plants young banana plants that grow from the side shoots of existing plants, so every plant on its farms is genetically identical. A fungal disease has begun to spread through banana farms in the region.

   (a)

   Compare sexual and asexual reproduction.

   [6 marks]

   (b)

   Discuss and evaluate the cooperative's decision to grow only genetically identical banana plants.

   [6 marks]

   Total for question 4: 12 marks

End of questions