The Nervous System Flashcards
What is the nervous system?
a complex network of nerves and cells that carry messages to and from the brain and spinal cord to various parts of the body.
What are the 2 main systems that comprise the Nervous System?
The Central Nervous System
The Peripheral Nervous System
What comprises the central nervous system?
The brain and spinal cord
What comprises the peripheral nervous system
The somatic motor system
the autonomic system
What comprises the autonomic system?
The sympathetic and parasympathetic nervous system
What is the function of the sympathetic nervous system?
When stimulated, nerves prepare the body for a fight or flight response
What is the function of the parasympathetic nervous system?
When a stressor has gone, it prepares the body for ‘rest and digest’ to maintain homeostasis
What are 3 changes the sympathetic nervous system makes to the body when stimulated?
Any from: Pupils dilate Digestion slows Heart rate increases Blood pressure increases Blood flow to skin decreases Blood flow to muscles increases Sweating increases Salivary gland production is inhibited
What are 3 changes the parasympathetic nerves makes to the body when stimulated?
Any from: Heart rate decreases intestinal activity increases Gland activity increases Sphincter muscles relax
What are 4 functions of the nerves system?
Any of: Maintain homeostasis Transmit electrical impulses from receptors to brain For Memory and learning Programme spinal cord reflexes Respond to stressors in the environment
Sensory input, info processing, motor output
What are 3 functions of the cerebrum and what is this part of the brain known as?
Front brain
initiates and co-ordinates movement, temperature, touch, vision, judgement, reasoning, emotions, learning and problem solving
What does the diencephalon do?
relays sensory and motor signals to the cerebral cortex – regulates consciousness, sleep, alertness – essentially processes sensory information and autonomic control
What does the brain stem do?
Regulates involuntary body actions like heartbeat and breathing
What does the cerebellum do?
Involved in motor control
Maintaining balance
Eye movement
Motor learning
What happens to the liver when the sympathetic nervous system is stimulated? And why?
Increases conversion of glycogen to glucose so more glucose is available to skeletal muscle and brain cells
What happens to the upper digestive tract when the sympathetic nervous system is activated?
Digestion slows/ stops in the stomach, duodenum, ileum and jejunum
What happens to the lower digestive tract when stimulated by the sympathetic nervous system?
Digestion slows/ stops in the large intestine (cecum, colon, rectum) and sphincter muscles contract
Why does blood flow to the skin decrease when the sympathetic nervous system is activated?
Because blood flow is redirected to muscles and away from non-essential parts of the body
Which part of the heart dilates when the sympathetic nervous system is activated?
The coronary blood vessels
What are effectors?
The part of the body that produces a response to stimuli - i.e: muscles
What are receptors?
Groups of specialised cells that detect changes in the external environment and turn the stimuli into electrical impulses along neurons
Where are receptors typically found?
In sense organs - ears, nose, mouth, tongue, skin
What are neurons?
Nerve cells that carry electrical signals between each other
What are the 3 types of neuron?
Sensory
Motor
Relay
