The Nervous System Flashcards
What are the two types of nervous system? 2
- Peripheral Nervous System
- Central Nervous System
What is the central nervous system? 2
- The brain
- The spinal cord
What is the peripheral nervous system?
All other neurones than in the brain and spinal cord including
- Sensory neurones
- Motor neurones
- Relay neurones
What are the two types of peripheral nervous system? 2
- Somatic nervous system
- Autonomic nervous system
What is the somatic nervous system? 2
- Voluntary and conscious
- Stimulates skeletal muscles
What is the autonomic nervous system? 2
- Involuntary and unconscious
- Stimulates smooth muscles, cardiac muscles and gland
What are the two types of autonomic nervous system?
- Sympathetic nervous system
- Parasympathetic nervous system
What does the sympathetic nervous system do?
Speeds up function i.e “fight or flight” response
What does the parasympathetic nervous system do?
Slows down function i.e “rest and digest”
What neurotransmitter does the sympathetic nervous system mainly use?
Noradrenaline
What neurotransmitter does the parasympathetic nervous system mainly use?
Acetylcholine
What are the 2 main purposes of having a nervous system?
- Increased chance of survival by responding to changes in external environment
- Keeps conditions optimal for metabolism by responding to changes in internal environment
Define “stimulus”
Any change in external/internal environment
Define “receptor”
Proteins/cells on cell surface membranes detecting stimuli
How are receptors specific?
They only detect one type of stimulus e.g light/pressure
Define “effector”
Cells bringing about a response to a stimulus to produce an effect
How do receptors and effectors communicate?
Via the nervous/hormonal system
Describe the nervous system arc 4
- Stimulus detected by receptor cells
- Electrical impulse sent along sensory neurone
- Reaches the end of the neurone, neurotransmitters send information to relay neurone which sends electrical impulse
- CNS processes info and sends impulses along motor neurones to effectors
Define endocrine gland
A group of cells specialised to secrete hormones
What stimulates glands?
Change in concentration of a specific substance/another hormone
