(a)   Define the following terms as used in genetic engineering:

            (i)     Restriction enzymes. 

            (ii)    Recombinant DNA.

            (iii)   Cloning.  (3,3,3 marks)

(b)     How are cereal plant important to mammals? (6 marks)

(c)      Describe how atmospheric nitrogen is made available for plant use. (5 marks)

                                                                                                                                         (Total = 20 marks)

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(a)   Define the following terms as used in genetic engineering:          (3,3,3 marks)

(i)      Restriction enzymes

These are enzymes used in genetic engineering which are used to cleave/cut DNA into small, shorter and simpler units.

(ii)    Recombinant DNA

This is a piece of DNA that has been produced artificially in the laboratory. It could comprise of one artificial and one natural strand of DNA or probably both strands being artificial.

(iii)   Cloning.

This is the process by which an identical copy of a part or whole organism is artificially produced.

(b)     How are cereal plant important to mammals?     (6 marks)

Cereals are important to mammals in that;

• They reduce the chances of cancer and can stop any proliferations
• Help in digestion.
• Helps in the control of diabetes.
•  Very rich in nutritive content

(c)      Describe how atmospheric nitrogen is made available for plant use                  (5 marks)

Atmospheric nitrogen is converted to soil nitrogen via the following methods.

• Nitrogen fixing bacteria like Azobacter found in the root nodules of leguminous plants help to transform atmospheric nitrogen to soil nitrates which are absorbable and usable by the plant.
• Also, thunderstorms convert atmospheric nitrogen to soil nitrates.

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THE END!!!

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You can check out:

Question one here: O/L Biology 2019 question one 2019 Answer | Alpha Study Group (alstug.com)

Question two here:O/L Biology 2019 question Two 2019 Answer | Alpha Study Group (alstug.com)

Question three here: O/L Biology 2019 question Three 2019 Answer | Alpha Study Group (alstug.com)

Question four here: O/L Biology 2019 question Four 2019 Answer | Alpha Study Group (alstug.com)

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