Chapter 3 pt.1 Flashcards
What is the Human Nervous System
Includes the spinal cord and the brain which sends and receives messages to and from all areas of your body. The nervous system is a maze of complex cellular networks that relay and process information (create behaviour)
Which two cells are in the nervous system
Neurons and Glial cells
What is the meaning of ‘Neural’
relating to the nervous system
What are Neurons
They are cells that communicate within the brain and with the body to form thoughts
What are Neurons
They are cells that communicate within the brain and with the body to form thoughts and actions
They code information as electrical signals and release chemical signals that influence other parts of the body
What are dendrites
They are extensions of the cell body that branch out to communicate with other neurone
What are the chemical signals called and what do they bind too
Neurotransmitters
They bind too receptors
What is excitation and inhibition
Excitation is when neurotransmitters tell the neutron to “activate” and Inhibition is when it tells it to quiet down
What are Receptors
Proteins in the cell body membrane that receive chemical messages from neurotransmitters.
When a neurotransmitter binds to a receptor it can influence the behaviour of the cell.
What is the Soma
The soma is the cell body of the neutron. It contains the organelle and controls the metabolic processing
What is the Axon
the long narrow projection from the cell body that acts as a wire transmitting the signal from the soma to the end of the axon (axon terminals)
What is the Axon Hillock
the axon hillock is the intersection between the soma (cell body) and the axon. It’s where the axon begins
what is the Axon Terminals
The part of the axon that releases the neurotransmitter when the action potential gets to it
What are the Terminal Buttons (synaptic knobs)
the ends of the axon terminal where the neurotransmitter exits
What are vesicles
little bubbles at the terminal button that store neurotransmitter molecules
What is the Synaptic Cleft
the space between two neurons, usually the axon terminal and the dendrite
What is the Synapse
The synapse is the small fluid-filled gap between neurons In which neurotransmitters are released
What are the Postsynaptic Receptors
It’s the other side of the synapse. The neuron that contains the receptors (usually dendrites) that are ready to bind to neurotransmitters released from the postsynaptic neuron
Whats Myelin
Myelin is a protein fatty substance that wraps around the axon to protect and increase speed of action potentials (electrical impulses)
It keeps the electrical impulse flowing down the axon
What are the Nodes of Ranvier
Gaps in the myelin that allow ions to enter into the axon and change the charge inside the cell, which allows for a more efficient signal transmission
What are the Nodes of Ranvier
Gaps in the myelin that allow ions to enter into the axon and change the charge inside the cell, which allows for a more efficient signal transmission
What are Ions? Name some
Ions are positive or negative charges, the movement of ions create electricity.
Na+ Cl- K+
When is a cell considered “Polarized”
When a large number of negatively charged ions inside the cell causes the neutron to have a negative charge
usually -70 Millivolts (mV)
When the cell is polarizes it is at rest and won’t release neurotransmitters
What is depolarization
When there are more positive charged particles in the cell causing the neuron to be positively charged
The more depolarized the neuron is, the more likely it is to activate (action potential) and send a neurotransmitter to another neuron/organ
