Structure your essay with a clear body paragraph dedicated solely to the advantages of GM crops, followed by another distinct paragraph exploring their disadvantages. As the question only asks "What are the advantages and disadvantages?", avoid taking a stance on which outweighs the other; simply present both sides objectively.

For advantages, consider discussing enhanced crop yields and resistance to pests or harsh environmental conditions, citing examples like Bt cotton's success in reducing pesticide use in India or drought-resistant maize. For disadvantages, explore potential ecological risks such as the development of herbicide-resistant 'superweeds' or concerns about the long-term impact on biodiversity and human health.

A common pitfall is discussing general agricultural issues or modern farming techniques without specifically linking them to genetic modification. To avoid this, ensure every point, whether an advantage or disadvantage, directly relates to the alteration of an organism's genetic material, such as enhanced nutritional value or the transfer of genes for pest resistance.

When transitioning from advantages to disadvantages, use strong contrasting discourse markers like "However, despite these potential benefits," or "Conversely, the adoption of GM crops is not without its critics." Within each paragraph, employ phrases such as "Furthermore," "In addition," or "Moreover" to introduce new points, and "Nevertheless," or "Nonetheless" for counterarguments if applicable within a point.

Examiners awarding band 8-9 for this question seek a nuanced discussion that demonstrates a deep understanding of the scientific, economic, and ethical dimensions of GM crops, not just surface-level pros and cons. This includes using precise academic vocabulary related to biotechnology and agriculture, presenting well-supported arguments with specific real-world examples, and maintaining a consistently objective tone throughout the analysis.