Learning Intention 2 Flashcards
To know: - how to describe a biological feedback system - conduct a valid experiment demonstrating the effect of a feedback system - to understand that multicellular organisms depend on the coordinated function of internal systems to achieve homeostasis (5 cards)
What is negative feedback
when the body’s response acts against the stimulus, for example pulling your hand away from a hot stove
What is positive feedback
when the body amplifies the stimulus and encourages change in the internal environment, for example labour
Example of positive feedback
- uterus contracts
- baby moves through birth canal
- stretch receptors activate
- brain releases oxytocin
Example of negative feedback
- heat from stove activates sensory
receptors in your skin - receptors send a signal through sensory
neurons to the spinal cord - spinal cord quickly processes information eithou waiting for the brain and sends a message
the effectors (hand muscles) pull your hand away
What is homeostasis
a state of balance among all body systems needed to survive and function correctly