Conservation and sustainabilityIB MYP Biology: Subtopic test

1. 1
   The Arabian oryx was hunted until it became extinct in the wild in 1972. A few animals survived in zoos and private collections. These animals were bred under human care, and their offspring were later released into protected reserves in Oman and the United Arab Emirates, where hunting is not allowed. The wild population has since grown to several hundred.

   (a)

   Which term describes breeding endangered animals under human care so that they can be released into the wild?

   [1 mark]

   • ASelective breeding
   • BNatural selection
   • CFishing quota
   • DCaptive breeding

   (b)

   What is the main purpose of releasing the oryx into a protected reserve?

   [1 mark]

   • ATo give the animals a habitat where they are safe from hunting and development
   • BTo make the animals easier to sell
   • CTo remove all predators permanently
   • DTo allow unlimited tourism

   (c)

   Explain one risk of building up a population from only a few animals.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A national seed bank wants to know how best to store the seeds of wild plants for conservation. Technicians collected seeds from one species of wild grass and divided them into two batches. One batch was stored at -18 °C and the other at 25 °C, both in sealed, dry containers. After five years they placed 100 seeds from each batch on damp filter paper at 20 °C and counted how many germinated in 14 days. From the batch stored at -18 °C, 94 seeds germinated. From the batch stored at 25 °C, 38 seeds germinated.

   (a)

   Which is the dependent variable in this investigation?

   [1 mark]

   • AThe temperature at which the seeds were stored
   • BThe temperature of the filter paper during germination
   • CThe number of seeds out of 100 that germinated
   • DThe time given for germination

   (b)

   Which is the best hypothesis for this investigation?

   [1 mark]

   • ASeed banks are important for conservation
   • BSeeds stored at a lower temperature will have a higher germination rate, because the cold slows the reactions that damage the seeds
   • CSeeds stored at -18 °C will grow into taller plants
   • DAll of the seeds will germinate whatever the temperature

   (c)

   Use the results to explain why seed banks store seeds at low temperatures.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   Cod fishing off the coast of Newfoundland, Canada, was so intense that the cod population collapsed in the early 1990s and fishing had to be banned for many years. Today many countries set a fishing quota for each species and require nets with a minimum mesh size.

   (a)

   Explain how quotas and a minimum mesh size help fish populations to recover.

   [3 marks]

   (b)

   Suggest two difficulties that quotas can cause for fishing communities, and explain why quotas are still needed.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A government wants to protect a tropical forest in Central America where wildlife numbers have fallen because of illegal hunting, logging and clearing for farms. Plan 1 would turn the whole forest into a national park, with rangers and a ban on logging, hunting and farming. Plan 2 would fully protect the core of the forest but allow local people to cut timber in a limited, planned way, replant every tree that is cut and farm the edges using sustainable methods. About 8000 villagers earn their living from the forest.

   (a)

   Explain how a protected area and replanting would each help to conserve the forest.

   [6 marks]

   (b)

   Evaluate Plan 1 and Plan 2 and decide which the government should choose.

   [6 marks]

   Total for question 4: 12 marks

End of questions