Describe and compare the following:

Mark scheme

Marking points from the official mark scheme (May/June 2019). The mark or mark type is shown in brackets.

1. [5] made of DNA ;
2. [5] part of a chromosome ;
3. [5] copied / passed on / inherited / hereditary;
4. [5] one + character(istic) / trait ;
5. [5] one + protein / polypeptide ;
6. [5] (allele) a form / type / version of a gene ;
7. [5] may be dominant / recessive / co-dominant;
8. [5] continuous
9. [5] over a range / many phenotypes / intermediates ;
10. [5] the result of interaction between genes and the environment ;
11. [5] valid example (skin colour, height, weight);
12. [5] discontinuous
13. [5] very few forms / few phenotypes / no intermediates ;
14. [5] the result of genes only;
15. [5] valid example (blood group, eye colour, sex) ;
16. [5] inherited / passed on to next generation ;