Week 3 Flashcards
Identify the five main parts of a neuron
- Dendrites
- Soma
- Axon
- Myelin Sheath
- Terminal Buttons
What do dendrites do, and where are they located?
Dendrites received stimulation from sensory receptors. And they protrude from the soma
What does a neural impulse travel along?
the axon
What contains neural transmitters located at the end of an axon?
Terminal buttons
What is the soma?
The neuron body.
Where does the metabolism of a cell take place?
soma
What converts sugar from the bloodstream for energy?
soma
What are the three major classes of neurons?
- sensory neurons
- motor neurons
- Interneurons
What class of neuron terminates on muscles and cause them to contract and relax?
Motor neurons
What class of neuron allows the brain to sense things such as smell, touch and hear?
Sensory neurons
What do interneurons do?
o From sensory neurons to other interneurons or to motor neurons. Most of the brain consists of interneurons
What is the one type of movement that doesn’t involve the central nervous system?
Reflex arc - pain withdrawal reflex
Is the signal within a neuron electrical or chemical?
Electrical
When the axon/neuron isn’t being stimulated is the signal positive or negative?
Negative
What makes the signal within the axon positive?
When it is stimulated
What is the voltage of a resting neuron?
-70 milivolts
What is the stimulated voltage of a neuron?
+30 milivolts
What is the all-or-none rule of an action potential?
the size of the action potential is unaffected by increases in the intensity of the stimulation beyond the threshold levels. It means that the spike is the same size no matter how stimulated the cell it.
What is the period during which further stimulation cannot cause another action potential, meaning that when the cell fires, there’s a rapid change, it cannot fire again until a couple of milliseconds have passes called?
The refractory period
T/F - At rest, a neuron is polarized with a negative charge inside the cell membrane and a positive charge outside (resting potential)
true
What part of a neuron stimulates an action potential?
dendrite
What do sodium irons flowing in to the axon achieve?
a positive charge - action potential
A neuron is polarized in a resting state. If it is depolarized what is it doing?
going from negative (-70) closer to positive. (neuron firing action potential)
What is happening when a neuron is hyperpolarized?
it’s going down or remaining negative (resting state)
A neurotransmitter can either have an inhibitory effect, or an excitable effect on the next neuron in the neuron pathway. If it has an inhibitory effect would it be depolarized or hyperpolarized?
Hyperpolarized (inhibitory)
A neurotransmitter can either have an inhibitory effect, or an excitable effect on the next neuron in the neuron pathway. If it has an excitable effect would it be depolarized or hyperpolarized?
depolarized (excitable)
Most of the neurotransmitters are made in the ____ and are transported down the axon and into the terminal buttons.
Soma
_________ are chemicals that transmit information from one cell to another
Neurotransmitters
What is the Acetylcholine (Ach) neurotransmitter?
The neurotransmitter you find at the motor-end plate It causes excitation which causes contraction of the muscle. they control the skeletal muscles and contribute to the regulation of attention, arousal and memory
What is the GABBA neurotransmitter?
The main inhibitory transmitter in the brain. If you have some type of excess of excitation in the brain the GABBA will inhibit them from firing.
What is the dopamine neurotransmitter?
Found in many locations in the brain but mostly in the mesolimbic pathway of the brain that is active when you are feeling ecstasy or pleasure. E.g drugs, sex, skydiving. Over activity in dopamine can cause schizophrenia
What are Norepinephrine/noradrenaline hormone and neurotransmitters?
Hormones that cause the release of adrenalin into the bloodstream as part of the autonomous nervous system – this occurs when you’re afraid and feel a spike of fear
What is the serotonin neurotransmitter?
found throughout the brain – the neurotransmitter of being in a good mood, feeling happy. If you lack serotonin you will be depressed and awake and maybe aggressive. Antidepressants are designed to boost serotonin. Very important as far as sleep/wake cycles are concerned.
What are Endorphins?
They’re neurotransmitters that are Naturally occurring opiates. Goal is to get rid of the feeling of pain and are released in response to pain
The neurotransmitter that regulates anxiety and that is used by about one-third of all the neurons in the brain is?
GABBA
The membrane of a neuron at rest is:
polarised. The inside of the cell membrane has a negative electrical charge while the fluid outside the cell membrane has a positive electrical charge
Inhibitory neurotransmitters:
a. affect the pre-synaptic neuron.
b. facilitate transmission at the synapse.
c. increase the number of receptor sites.
d. hyperpolarise the post-synaptic neuron
D - hyperpolaize the post synaptic neuron
The electrical difference be
tween the inside and outside
of a resting neuron is
-70
Narcotics work because they are chemically very similar to what neurotransmitter?
Endorphin’s
What are the two cerebral hemispheres connected by?
corpus callosum
Which neurotransmitters increase the polarization of the postsynaptic
membrane?
inhibitory
People with excessive levels of dopamine may experience:
schizophrenia
The ability to feel a wedding ring on your finger and to see the cat running through a room requires a normally functioning _______ lobe.
parietal
As I watch the sun rise or as I look at a painting, the _____ lobe is the most active.
Optical
The fact that language is located more
in the left hemisphere is an example of:
lateralisation
My patient is producing ‘word salad’. He most likely has damage to:
Wernicke’s area
Jamie has been described as ‘left-brained’. Typically, it means he is
Logical and analytical
A brain-injured patient appears callous, grandiose, and boastful, and tends to make tactless comments. The area of the brain that is most probably damaged is the:
Frontal Lobe
