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Write an essay on one of the topics below - AQA - A-Level Biology - Question 7 - 2019 - Paper 3
Question 7
Write an essay on one of the topics below. EITHER The importance of DNA as an information-carrying molecule and its use in gene technologies. OR The importance o... show full transcript
Worked Solution & Example Answer:Write an essay on one of the topics below - AQA - A-Level Biology - Question 7 - 2019 - Paper 3
Step 1
The importance of DNA as an information-carrying molecule and its use in gene technologies.
Answer
The Importance of DNA as an Information-Carrying Molecule
DNA, or deoxyribonucleic acid, is a molecule that contains the biological instructions that make each species unique. Its primary function is to store and transmit genetic information essential for the growth, development, functioning, and reproduction of all living organisms.
Structure of DNA
DNA is structured as a double helix, composed of two strands that coil around each other, featuring a backbone made of sugar and phosphate groups, with nitrogenous bases (adenine, thymine, cytosine, and guanine) paired in the interior. This specific pairing is crucial for accurate replication and transmission of genetic material.
Functions of DNA
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Genetic Information Storage: DNA stores the genetic information necessary for constructing proteins. The sequence of bases along the DNA molecule determines the sequence of amino acids in proteins, which are vital for cellular functions.
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Replication: During cell division, DNA undergoes replication, ensuring that each new cell receives an exact copy of the genetic material. This process is facilitated by enzymes such as DNA polymerase, which adds nucleotides complementary to the template strand.
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Transcription and Translation: DNA plays a critical role in gene expression through processes of transcription (where RNA is synthesized from a DNA template) and translation (where proteins are synthesized from RNA).
Applications in Gene Technologies
DNA's role as an information-carrying molecule extends to gene technologies, which harness DNA for various applications:
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Genetic Engineering: Techniques such as CRISPR-Cas9 allow scientists to edit genes within organisms to study gene functions and develop traits such as disease resistance in crops.
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Cloning: DNA cloning enables the production of identical copies of specific DNA segments, useful for research and medical applications. For instance, insulin production for diabetes treatment uses cloned DNA to produce insulin in bacteria.
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Forensic Science: DNA evidences such as fingerprints aid in criminal investigations, enabling identification of individuals based on unique DNA profiles.
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Gene Therapy: This emerging field aims to treat or prevent diseases by introducing corrected genes into patients, demonstrating the therapeutic potential of manipulating genetic information.
Conclusion
In summary, DNA is pivotal as an information-carrying molecule, guiding the biological functions in organisms and driving innovations in gene technologies. Its study not only enhances our understanding of genetics but also opens avenues for advancements in medicine and biotechnology.