Lesson 4 of 8

Chromosomes, genes and DNA

Goal: Describe how DNA, genes and chromosomes are related.

Puzzles for this lesson

Your genetic information is stored as DNA, on the chromosomes in the nucleus of your cells.

Chromosomes are in the nucleus. A human body cell has 46 of them, in 23 pairs. One of each pair came from the mother and one from the father.
A chromosome is made of DNA: a very long thread of it, coiled up tightly.
A gene is a short section of DNA. Genes control inherited features, and many features depend on several genes. One chromosome carries many genes.
A gene can come in different versions. That is why people have different blood groups.

Your turn

This lesson’s activity starts here in a moment.

I can put nucleus, chromosome, gene and DNA in order of size.I can label them on a diagram.

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Chromosome A thread of tightly coiled DNA that carries many genes

DNA The chemical that holds genetic information

Gene A section of DNA that controls an inherited feature

For teachers: AQA 3.10.4 · Cambridge 9Bs.03