Biology 9700 · AS & A Level · Gene control

Gene control — practice question

Plant physiology is influenced by environmental factors such as light intensity.
(a)[1]

Use the letter X to mark a point on the sketch graph in Fig. 8.1 at which light intensity is limiting the rate of photosynthesis.

(b(i))[1]

State the name of the enzyme that makes cDNA from an mRNA template.

(b(ii))[1]

State the name of the type of proteins that regulate gene expression in plants.

(b(iii))[3]

Suggest why a greater number of genes were switched on only in plants growing in high light intensity than in plants growing in low light intensity, where fewer genes were switched on.

Worked solution & mark scheme

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