Introduction to Homeostasis
Introduction to Homeostasis
Definition
- Homeostasis is a process used by many organisms to maintain a stable internal environment, despite changes in external conditions.
- This involves balancing inputs with outputs, and maintaining optimal conditions for cell functioning.
Importance of Homeostasis
- Homeostasis is crucial to support normal physiological activities and to handle stresses.
- It primarily controls three core aspects: the concentration of oxygen and carbon dioxide, the pH and the concentration of nutrients and waste products.
- Alterations to these aspects can lead to cell dysfunction or even death.
Mechanisms of Homeostasis
- Homeostatic control mechanisms have three interdependent components: a receptor, a control centre (or integrator) and an effector.
- The receptor detects changes in the conditions of the environment and sends the information to the control centre.
- The control centre processes the information and commands the effector to respond and restore the conditions to the norm.
- This process is known as a feedback loop. If the response decreases the original stimulus, it is termed a negative feedback loop. If the response increases the original stimulus, it is termed a positive feedback loop.
- Negative feedback loops are more common in nature and stabilise the system, while positive feedback loops are less common and usually exacerbate the system’s response.