Responding to the Environment

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Across:

2. Type of rhythmical behaviour that occurs every 24 hours. (9,6)
4. Piece of apparatus used to study environmental factors affecting an animal's behaviour. (6,7)
5. General term used to describe a behaviour pattern that is repeated at definite intervals. (10,9)
6. General term for a behaviour pattern that occurs once a year. (6,6)
8. Reaction shown by an organism on being exposed to a stimulus. (8)
10. Term describing a rhythm where most of the activity is at night. (9)
11. Type of behaviour that occurs in response to the movements of the sea. (5,6)
12. Type of behaviour where an animal moves from one region to another for favourable conditions. (9)
13. Term describing a rhythm where most of the activity is during the day. (7)

Down:

1. Part of an animal's nervous system thought to exert internal control over rhythmical behaviour. (10,5)
3. Environmental stimulus that initiates a specific response. (8,7)
7. Type of behaviour where an animal survives the winter in a state of prolonged inactivity. (11)
9. General term for a factor that brings about a response. (8)