Topic 1: The Nervous System Flashcards
What is the nervous system?
A complex system of nerves and cells that carries messages around the body
What are the 2 main parts of the Nervous System?
- Central Nervous System (CNS)
- Peripheral Nervous System (PNS)
What is the CNS?
composed of the brain and spinal cord. allows the brain to connect with the rest of the body. It recieves sensory information, proccesses the information, and sends out motor signals
brain = control centre of the body
spinal cord = communicate with rest of body
What is the PNS?
Any nerve outside the brain and spinal cord. It communicated information from body organs, glands, and muscle to the brain (and the other way around)
What is the subdivision of the PNS?
- Somatic NS
- Autonomic NS
What is the Somatic NS
controls the voluntary movement of muscles and the processing of sensory information from the external environment
Motor Neurons: communicate messages away from CNS to a particular muscle that intends to move
Sensory Neurons: carry messages from our senses to our brain so it can interact with the environment It goes towards CNS.
What is the Autonomic NS?
it controls the body’s non-skeletal muscles (eg heart, pupil), internal organs, and glands. it is involuntary movements that carry out the basic bodily functions essential for survival.
What are the subdivisions of the Autonomic NS?
- Sympathetic
- Parasympathetic
What is the sympathetic NS?
a network of nerves that helps activate the bodys fight-or-flight repsonce when it senses danger.
What happens during fight or flight?
It prepares our body for sudden stress. It is our body’s natural response to danger.
- Heart beat increases, pupils dilate, airways relax, digestive system pauses, and increase in blood flow.
What is the freeze response
It is fight-or-flight on hold eg; hiding
What is the parasympathetic NS?
Calms our body down and returns it to baseline/normal. Called ‘Rest & Digest’
- Slower heartbeat, constricted pupils and airways, the digestive system resumes.
