IBDP Biology Question Analysis Topic: Biology - Short Questions
Exam Questions:
1) Since the origin of life on earth, there were five episodes of mass extinction of species.
(i) How is the 'sixth extinction', presently in progress, different from the previous episodes?
(ii) Who is mainly responsible for the 'sixth extinction'?
(iii) List any four points that can help to overcome this disaster.
2) Write the location and function of the following in human testes:
(a) Sertoli cells (b) Leydig cells
Answers:
For IBDP Biology, you should know:
1) (i) The following are some ways that the sixth extinction differs from earlier ones:
Reduction in the number of species per unit area per unit time happens quickly.
Human activities like industrialization and deforestation speed it up.
(ii) This sixth extinction is a result of human activities that ultimately cause global warming and upset the ecological and environmental balance.
(iii) Such a disaster can be overcome by:
(1) Reforestation
(2) Reducing the overexploitation of natural resources
(3) Conservation of species and their natural habitats to minimize losses
(4) Raise people's consciousness about global warming and its effects.
2) (a) The seminiferous tubules of the testes contain sertoli cells.
They provide nutrition for the sperms as they grow.
(b) In the interstitial spaces between the seminiferous tubules are the Leydig cells.
They synthesize and secrete androgen hormones, such as testosterone.
Work hard for your IBDP Biology examination!
End of analysis. Great!
