Anna has a farm that grows fruit. She has a system that monitors the conditions for growing the fruit. Sensors are used in this system.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2017). The mark or mark type is shown in brackets.

1. [1] (a) It is an input device
2. [1] (a) It measures/takes (physical) readings of the surrounding environment / environment by example / physical properties
3. [1] (b) Moisture (sensor)
4. [1] (b) To measure the water content of the soil
5. [1] (b) To alert when the soil is too dry or too wet/needs watering
6. [1] (b) pH (sensor)
7. [1] (b) To measure how acidic/alkaline the soil is
8. [1] (b) To alert when there may be something polluting the soil
9. [1] (b) Light (sensor)
10. [1] (b) To measure the brightness of the environment
11. [1] (b) To alert when the fruit has too little/too much light
12. [1] (b) Temperature (sensor)
13. [1] (b) To measure the temperature of the environment
14. [1] (b) To alert when it is too hot/too cold for the fruit to grow
15. [1] (b) Gas (sensor)
16. [1] (b) To measure the amount of CO2/oxygen present
17. [1] (b) To alert when too much CO2/oxygen present
18. [1] (b) Humidity (sensor)
19. [1] (b) To measure the water content in the air
20. [1] (b) To alert when the air is too dry
21. [1] (b) Infra-red / motion (sensor)
22. [1] (b) To measure level of infra-red/microwaves deflected
23. [1] (b) To alert to any intruders e.g. animals stealing the fruit