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Edexcel IGCSE Biology · Spec 3.14-3.15

DNA, Genes and Chromosomes

The relationship between DNA, genes and chromosomes, and the structure of a DNA molecule.

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DNA, Genes and Chromosomes

Spec 3.14-3.15

What you need to know

  • Recall that chromosomes are found in the nucleus
  • Link chromosomes, genes and DNA
  • Define gene and genome accurately

Active recall

Quick check

Answer each question before opening the answer.

Define a gene and a chromosome.

A gene is a section of DNA that codes for a protein; a chromosome is a long DNA molecule carrying many genes.

Describe the structure of DNA.

A double helix of two strands held together by complementary base pairs: A with T, and C with G.

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