2.5 Homeostasis & Nervous System Flashcards
Define Homeostasis
Homeostasis is the regulation of the internal conditions of a cell or organism, in order to maintain the optimum conditions for function, in response to internal and external changes
Homeostasis maintains the optimal conditions for ____________ and all ____________
Homeostasis maintains the optimal conditions for enzyme action and all cell functions
What are 3 conditions controlled by homeostasis?
- Body Temperature
- Water levels (in body)
- Blood Glucose concentration
What happens if the body temperature is too high?
If the body temperature is too high, enzymes would denature, which would cause many reactions to stop
What happens if the body temperature is too low?
If the body temperature is too low, enzyme activity would slow down
What happens if the water levels are not controlled?
If the water levels are not controlled, cells could gain or lose water by osmosis, causing the cells to swell or shrink
What happens if the blood glucose concentration falls?
If the blood glucose concentration falls, less glucose will be available for respiration so less energy is available for cell activities (like active transport)
What are automatic control systems?
Automatic Control Systems is the way the body detects and responds to changes in the external environment
Name 2 Automatic Control Systems
- Nervous System
- Endocrine System
What do all biological control systems include?
- Receptors
- Coordination Centres
- Effectors
What is a stimulus?
A stimulus is a change in the environment
What are Receptors?
Receptors are the cells that detect stimuli
What are Coordination Centres?
Coordination Centres are the areas that recieve and process the information from the receptors
What are Effectors?
Effectors are the muscles or glands that carry out responses to restore the body conditions to optimum levels
What does the nervous system enable humans to do
The nervous system enables humans to:
- React to their surroundings
- Coordinate their behaviour