Biology Ch 16 Flashcards
2 systems of human nervous system
- CNS (Central Nervous System)
- PNS (Peripheral Nervous System)
What are included in CNS?
- Brain 2. Spinal Cord
What are included in PNS?
- Cranial Nerves
- Spinal Nerves
How the cranial nerve linked?
From receptors and effectors in head and neck to brain
How the spinal nerve is linked?
From the rest of the body to spinal cord
What are the structure in neurones
Cell body (nucleus), nerve fibres (Axons, dendrons)
How do dendrons work?
- Transmit nerve impulse towards cell body
- Branches into dendrites
How do axons work? (A.A.A.)
- Transmit nerve impulse away from cell body
- Branches into synaptic knob -> containing neurotransmitter
What covers the nerve fibres?
Myelin Sheath
What are the functions of myelin sheath?
- Insulate nerve fibres
-> prevent transmission to. surroundings - Speed up transmission
Types of neurones
Sensory neurones
Interneurones
Motor neurones
Direction of nerve impulse transmission
Sens: Receptors -> CNS
Inter: Sens -> Motor
Motor: CNS -> effectors
Appearance of sensory neurones
Long dendrons, short axon
Appearance of interneurones
Short dendrons, short axons
Appearance of motor neurones
V. short dendrons, long axon
Connections of neurones
Sens: connect receptors
Inter: connect dendrons and axon
Motor: connect effectors
Process of transmission of nerve impulse
- Arrive at synaptic knob
- Neurotransmitter released
- Diffuse across synaptic cleft
- Binds to specific protein effectors
- Stimulate dendrons -> generate nerve impulse
Importance of synapses
- Allow nerve impulse travel only in one direction
- Allow to communicate with many other neurones -> coordination
