Biology 9700 · AS & A Level · Principles of genetic technology

Principles of genetic technology — practice question

Soybean, Glycine max, is a major crop used for human food and for animal feed. Two soybean varieties are Vinton 81 and GTS 40-3-2. Vinton 81 was produced by the conventional method of selective breeding (artificial selection), whereas GTS 40-3-2 is an example of a genetically modified (GM) organism.
(a)[4]

GTS 40-3-2 is described as herbicide-resistant because it can survive treatment with glyphosate herbicide. Glyphosate is sprayed onto the crop to kill weeds. Outline how genetic engineering gave GTS 40-3-2 the trait of herbicide resistance.

(b)[5]

Countries differ in how far they grow GM varieties, such as GTS 40-3-2, instead of traditional varieties such as Vinton 81. In the USA, $94\%$ of soybeans grown are GM. In Europe, $0\%$ of soybeans grown are GM. Scientists used computer models to predict the effect of two different changes in agricultural practice on soybean crop yields: • a global ban that reduces the cultivation of GM soybeans to $0\%$ everywhere • all countries increasing the cultivation of GM soybeans to the $94\%$ level of the USA. Table 3.1 shows the results of this modelling for four countries. Explain what the data in Table 3.1 suggests about the social and ethical implications of growing GM soybeans.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Herbicide-resistance gene from another species

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI