Nervous System Flashcards
What are the two division of the Nervous System and their functions?
Peripheral Nervous System: Carries information between body organs and CNS.
Central Nervous System: Coordinates and Integrates information.
What is the difference between Autonomic NS and Somatic NS?
Autonomic NS: Controls HOMEOSTASIS. Not able to control organs.
Somatic NS: Controls our muscles and body.
Division of Autonomic NS and Somatic NS and their functions?
Autonomic NS:
-Sympathetic NS: adjusts and responds to stress. “ Fight, Flight, Freeze”
-Parasympathetic NS: recovers from stress. “Reset and Digest”
Somatic NS:
-Motor (efferent): carries information from CNS to skeletal muscle; initiates response. (moves from brain to body)
-Sensory (affarent): carries information from environment to CNS. (moves from body to brain)
What are the two division of CNS?
Brain and Spinal Cord
How does the following respond from Sympathetic NS to Parasympathetic NS
Heat Rate
Blood Pressure
Breathing Rate
Digestion Rate
Blood Sugar
Liver
Bronchioles
Pupils
P.S think about that you are in a zombie apocalypse
Sympathetic Parasympathetic
HR: up down
BP: up down
BR: up down
DR: down up
BS: up down
L: glycogen>glucose glucose>glycogen
Br: dilates (open) constrict (close)
P: dilates (open) constrict (close)
Impulse Pathway Through The Neuron
Dendrites > Cell Body > Axon > Axon Terminal
What is Dendrites and its Function?
receives information from a receptor or another neuron.
What is Cell Body and its Function?
Control centre of the neutron; contains nucleus.
What is the difference between axon and axon terminal?
Axon: Long extension of cell body, carries signal away from cell body.
Axon Terminal: branched endings of the axon.
What is Schwann Cell/ Glial Cell and its function?
white and fatty cell that supports the axon.
What is Myelin Sheat and its function?
also known as neurillema. It protects the axon and increases the speed of impulse.
What is Node of Ranvier and its function?
are the spaces between the Schwann cell. It allows impulse to “jump” from node ( saltatory conduction) increasing the speed of transmission.
What is end plates?
secretes neurotransmitters needed to carry message to next neutron.
What is a reflex?
are involuntary and often unconscious act. It occurs without brain coordination.
How does a reflex arc work?
clue: RSIME
- Receptor is stimulated.
- Sensory Neuron relays information to the spinal cord. ( PNS > CNS)
- Interneuron receives the the information and sends the impulse to motor neuron.
- Motor Neurone receives the impulse and relays it to the effector.
- Effector is activated by motor neuron. It creates response.
How to differentiate Motor Neuron and Sensory Neuron in a diagram?
Motor Neuron:
Its cell body is located in CNS; axon terminal/axon is short and visible.
Sensory Neuron:
Its cell body is located outside CNS; only has one axon terminal/ end plate; has longer axon; Impulse moves from receptor to CNS.
What is an action potential?
is an electromechanical process that results from the movement of ions across a neutrons semipermeable membrane.
What are the five steps of action potential and what they do?
clue:
1. negative charge
2. becomes positive charge
3. becomes negatives charge
4. becomes more negative charge
5. repeat
- Resting Potential (Polarization): it has a negative charge because there are more positive ions outside neutron than inside. It has 2 potassium inside neuron and has 3 sodium outside.
- Depolarization (Action Potential): sodium channel opens, allowing sodium to enter neuron, it becomes positive charge.
- Repolarization: sodium gates close and potassium gates open, potassium leaves neuron. It results of neuron becoming more negative charge.
- Hyperpolarization: The neuron becomes even more negative than resting potential.
- Resting Membrane ( Polarization): sodium and potassium puts neuron to resting potential, bring potassium in axon and removes potassium in axon. Cell cannot fire until cell returned to resting potential ( this is called refractory period).
What is the Threshold Levels?
clue: all or nothing
The minimum stimulus is required for an action potential to occur. It’s either neurone will fire at a max or not all.
What are the two ways we can detect different intensities?
clue:
1. Frequency
2. Number of Neurone
- Increased frequency of impulse.
- Increased number of neurone sending impulse.
What is a Synapse?
Synapse are the spaces between two neurons.
What are the steps of a synaptic transmission?
- Impulse reaches synapse from axon.
- Vesicles in axon terminal releases neurotransmitter.
- NT diffuse across synapse.
- NT attaches to receptors on the dendrites of postsynaptic neuron.
- Postsynaptic Neuron can either depolarize or hyperpolarize.
- Enzymes remove NT from synapse.
Two types of Neurotransmitters?
Excitatory Neurotransmitters: cause depolarization (sends message) by opening Na+ channels on postsynaptic neuron.
Inhibitory Neurotransmitters: cause hyperpolarization (stops message) by opening K+ channels on postsynaptic neuron.
Two common types of NT?
- A
- N
Acetylcholine: can be excitatory/ inhibitory.
Norepinephrine: a stress hormone.
