How to Revise Communication and homeostasis — OCR A-Level Biology
Communication and homeostasis is a topic in the OCR A-Level Biology specification. This guide covers learning objectives, examiner tips, common mistakes, and key terminology to help you revise effectively.
Examiner Tips for Communication and homeostasis
- Ensure you can clearly define homeostasis as the maintenance of a stable internal environment.
- Use precise terminology when describing feedback loops; always state that negative feedback returns a system to the 'set point'.
- When discussing thermoregulation, explicitly link the response to the maintenance of enzyme activity.
- Practice interpreting data or scenarios involving temperature control in different organisms.
Common Mistakes in Communication and homeostasis
- Confusing negative feedback with positive feedback mechanisms.
- Failing to distinguish between physiological and behavioural responses.
- Inaccurate description of the role of the hypothalamus in temperature control.
- Vague terminology when describing how receptors detect changes in the internal environment.
Key Marking Points
- Distinction between receptors and effectors in homeostatic control systems.
- Explanation of negative feedback as a mechanism to restore a set point.
- Explanation of positive feedback as a mechanism that amplifies a change.
- Physiological responses for temperature control in endotherms (e.g., vasodilation/vasoconstriction, sweating, shivering).
- Behavioural responses for temperature control in ectotherms (e.g., basking, seeking shade).
- Role of the hypothalamus in thermoregulation.