DP Biology (last assessment 2024)
Question 18M.2.HL.TZ1.a.ii
| Date | May 2018 | Marks available | [Maximum mark: 1] | Reference code | 18M.2.HL.TZ1.a.ii |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | State | Question number | a.ii | Adapted from | N/A |
a.ii.
[Maximum mark: 1]
18M.2.HL.TZ1.a.ii
The land snail Cepaea nemoralis is very common in North America and in Europe.
The base colour of its shell varies between brown, pink and yellow, and also in its intensity. Some shells are unbanded, but most show one to five bands of different width on top of the shell base colour.
State the major chemical component of the shell in molluscs.
[1]
Markscheme
calcium carbonate/CaCO3
Do not accept carbon or calcium – the mass of oxygen in calcium carbonate is greater than both these and the chemical component is the compound not its constituent elements.
