Chapter 7.2 Neurons Flashcards
The Central Nervous System
Is made up of the brain and the spinal cord. Receives and processes information before initiating a response. Made up of white (myelinated axons) and grey (cell bodies) matter.
The Peripheral Nervous System
Branches out to the rest of the body and carries messages to/from the CNS.
What is a nervous system?
A communication network that controls all the other systems in the body.
What are neurons?
Neurons are nerve cells that make up the nervous system, they transmit electrical messages called nerve impulses around your body at high speeds and in one direction.
What is the Structure of a Neuron?
Neurons contain a nucleus, cytoplasm, and a cell membrane like regular animal cells. Specialized cell parts include dendrites, an axon, and axon terminals.
What are dendrites?
Dendrites are specialized parts in nerve cells that receive messages from other nerve cells.
What is an axon?
An axon is a specialized part in a neuron that sends nerve impulse away from cell body. It is coated in white fatty cells called Schwann cells, that form the myelin sheath, to insulate the axon, also making electrical impulses travel quicker.
What is an axon terminal?
Axon terminals are specialized parts in a neuron that pass the message on to the next neuron.
Sensory Neurons
Carries messages from cells in sense organs (eyes, ears, tongue, skin) to the CNS.
Relay Connector Neurons
Transmit messages between neurons in the CNS. (Brain or Spinal cord)
Motor Neurons
Carry messages from the CNS to effectors e.g. muscles that translate messages into actions
What is an action potential?
When a neuron has been stimulated, a nerve impulse or electrical signal travels down an axon.
What is a neurotransmitter?
When the nerve impulse reaches the axon terminal, special chemicals called neurotransmitters are released into the synapse (space between neurons), stimulating the dendrites of the next neuron.
