Topic 5.1- 5.2: Homeostasis and nervous system Flashcards
Define Homeostasis
the regulation of conditions inside the body to maintain a stable internal environment, in responses to changes both internal and external conditions
What does an automatic control system do
recognise when there is a change from optimal conditions and send a signal to reverse that change
What are the three key components of an automatic control system
- receptors -> detect a change
- coordination centres -> interpret change and decide what needs to be done
- effectors -> carry out necessary change
What makes up the coordination centre
brain and spinal cord
What are the effectors in the body
muscles and hormones
explain what negative feedback is
the reversing of the stimulus/change
What are the main adaptations of a nerve cell and what is its purpose
adaptions -> long and thin with lots of branches
for -> to carry eletrical impulses
what is the gap between two neurons called
synapse
How are electrical impulses passed from one neuron to the next
the impulse releases a chemical which travels across the synapse and causes another electrical im[ulse tobe released
what is the central nervous system
our brain and our spinal cord
What carries information from the receptors to the CNS
Sensory neurones
What carries information from the CNS to the effectors
motor neurones
What is the reflex arc
the nerve pathway that underlies all our subconscouis actions and they are rapid and automatic
What is the chain of reaction in a reflex arc
stimuli (Pin) -> Receptors (skin cells) -> sensory neurone -> relay neurone inside CNS (spinal cord) -> motor neurone -> effector (muscles)
