Describe the structure of a DNA molecule: (a) two strands coiled together to form a double helix (b) each strand is made up of a chain of nucleotides (c) each nucleotide contains a base (A, T, C, G; full names are not required) (d) bonds between pairs of bases hold the strands together (e) the bases always pair up in the same way: A with T, and C with G
Understand that chromosomes contain DNA, which carries genetic information in the form of genes
Describe a chromosome mutation as a change in the chromosome number or structure, using Down’s syndrome as an example (47 chromosomes instead of 46)