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Miracle Learning Centre Science Tuition Question on Food Chain/Web. (O Level Science Tuition/IP Science Tuition/Secondary Science Tuition)

1 The cane toad, a native of Africa, was introduced into the sugar cane plantations of Australia. The cane toad has the following characteristics:

• It was able to adapt to many different environmental conditions. • It has a poison in its skin, which is deadly to predators. • A single female can produce 30 000 eggs in one year. • It can live up to 30 years. • The cane toad was thought to provide an effective agent for a biological method of pest control. The food web below shows the feeding relationships in the sugar cane plantation.

(a) Based on only the food web shown above, give one reason why the cane toad was an effective agent for a biological method of pest control. ________________________________________________________________ ______________________________________________________________[1]

(b) State two advantages of using the cane toad to control the sugar cane pests compared to using a pesticide. ________________________________________________________________ ______________________________________________________________[2]

(c) After using the cane toad for some time, scientists realised that they had upset the ecosystem in the plantations. Suggest two populations of organisms that were affected and how the cane toads affect these populations. ________________________________________________________________ ________________________________________________________________

(d) Scientists are carrying out genetic engineering to make the sugar cane plant itself resistant to pests. (i) Explain what is meant by the term genetic engineering. ________________________________________________________________ ______________________________________________________________[1] (ii) Describe how genetic engineers can produce pest-resistant sugar cane plants once they found the pest-resistant gene. ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ______________________________________________________________[5] [Total: 13]

Miracle Learning Centre Answer to Science Tuition Question on Food Chain/Web. (O Level Science Tuition/IP Science Tuition/Secondary Science Tuition)

Learn from our Science Tuition Questions and Answers. Miracle Learning Centre Call 6463 8756 or sms 8128 8342/9839 9908. (Specialist in Science and Maths) for Primary, Secondary and JC levels. Miracle Learning Centre specialises in Science tuition, Maths tuition, Chemistry tuition and Physics tuition classes.