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QuietDragon2728

Good afternoon,

I don’t really understand the difference between gene, chromosome, DNA and genome?

Can you help me?

Thank you!

Éveline O

Thanks for your question!

First of all, deoxyribonucleic acid, or DNA, is a type of molecule that stores hereditary information in living things. DNA is in the form of a double helix. In reality, it is made up of multiple subunits called nucleotides. There are four types of nucleotides: adenine, thymine, guanine, and cytosine. In the structure of DNA, adenine is always paired (attached) with thymine, and guanine is always paired with cytosine.

Genes are made up of DNA. Physically, a gene corresponds to a very precise series of nucleotides. However, when a series is translated, it codes for a very specific protein in a living organism.

Chromosomes are masses of DNA that contain multiple genes. They form two centrally connected strands during cell division, giving them a distinctive X shape. In humans, there are 23 different chromosomes.

The genome is made up of all the genes of a living organism.

To visualize these different genetic terms, let's take the analogy of a cookbook:

• Letters are nucleotides

• Words are DNA

• Recipes are genes

• Chapters in the book are chromosomes

• The book as a whole is the genome

I hope this helps you a bit.

Do not hesitate if you have other questions!