Home > Subjects > Biology > Level 3 > 3.4 Internal Environments > Subject content
- Subject: Biology
- AS: AS 91604
- Level: 3
- Credits: 3
- Internal
Biology 3.4 Demonstrate understanding of how an animal maintains a stable internal environment
Subject content
Control systems that maintain a stable internal environment (homeostatic system) include those that regulate:
- body temperature
- blood pressure
- osmotic balance
- level of blood glucose
- levels and balance of respiratory gases in tissues.
The biological ideas related to the control system includes the:
- purpose of the system
- components of the system
- mechanism of the system (how it responds to the normal range of environmental fluctuations, interaction and feedback mechanisms between parts of the system)
- potential effect of disruption to the system by internal or external influences.
Environmental influences that result in a breakdown of the control system may be external influences such as extreme environment conditions, disease or infection, drugs or toxins, or internal influences such as genetic conditions or metabolic disorders.
