Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
33 Cards in this Set
- Front
- Back
|
Function of Nervous System |
Control and integration of all body activities. Essentail to regulating homeostasis. 1. Sensory changes 2. Interpreting and remembering changes 3. Reacting to changes with effectors |
|
|
Central Nervous System (CNS) |
Consists of the brain and spinal cord. |
|
|
Peripheral Nervous System (PNS) |
Consists of cranial and spinal nerves that contain both sensory and motor fibers (mixed nerves). Connects CNS to muscles, glands and all sensory receptors.
|
|
|
PNS Three Subdivisions |
1. Somatic (SNS) - voluntary Skeletal muscle only. 2. Autonomic (ANS) - involuntary Sympathetic and parasympathetic divisions 3. Enteric (ENS) - involuntary Digestive system |
|
|
Structures of the PNS |
12 pairs of cranial nerves 31 pairs of spinal nerves Ganglia Enteric plexuses Sensory receptors |
|
|
Structures of the CNS |
Brain. Connected to Spinal cord via foramen magnum. |
|
|
Functional classification of neurons |
Sensory - Afferent Feed sensory information to CNS Motor - Efferent Conduct impulses to muscles and glands Interneurons - connect sensory to motor neurons. Makes up 90% of neurons. Mostly in CNS. |
|
|
Neurons |
Nerve cells. Convert stimuli into nervous impulses and conduct nerve impulses to the other cells. Excitable. Generate and propagate APs. |
|
|
Neuroglia |
Protective and supporting cells. Not excitable. |
|
|
Neuron - Structure |
Cell body: single nucleus, nissl bodies, neurofilaments, microtubules, lipofuscin. Cell processes: Dendrites and axon. |
|
|
Nissl bodies |
Composed of ribosomes |
|
|
Microtubules of Neurons |
Run through the axon of cell. Transports materials inside cells. |
|
|
Lipofuscin |
No known function. Harmless |
|
|
Dendrites - Structure |
Form the neuron network, connecting neurons to each other and other body cells (muscle) Short highly branched processes. Unmyelinated Contain neurofibrils and nissl bodies. |
|
|
Dendrites - Function |
Surfaces specialised for contact with other cells. Conduct impulses towards the cell body. |
|
|
Axons - Structures |
One per cell. Long thin cylindrical process of neuron. Conducts impulse away from the cell body. May of may not be myolinated by schwann cells. Conducts impulses from initial segment (trigger zone), propagated along the axon to synaptic end bulbs of axon terminals. |
|
|
Axon Transport |
Fast transport - Both direction Slow transport - One way. |
|
|
Neuron Structural Classifications - 3 types |
Multipolar Bipolar Unipolar |
|
|
Multipolar |
Several dendrites. One axon. Most comon cell in body. Eg: SMN |
|
|
Bipolar |
One main, highly branched dendrite. One axon. Specialised cells - Retina, inner ear or olfactory. |
|
|
Unipolar |
One process only. (develops from a bipolar cell). Highly branched single dendrite. Function as sensory neurons. Lots of free nerve endings |
|
|
Ganglian |
Clusters of cell bodies in PNS |
|
|
Nucleus |
Clusters of cell bodies in CNS |
|
|
Bundle |
Group of axons located in the PNS Connects brain to the periphery cranial nerves. |
|
|
Tract |
Group of axons in the CNS Interconnect neurons in spinal cord and brain |
|
|
Neuronal circuits/networks Function |
A functional group of neurons that process a specific type of information. A circuit may be responsible for breathing, waking up, short term memory, etc. |
|
|
Neuronal circuits/networks Structure |
- Contains thousands - millions of neurons - Arrangement classifications: Simple series. Diverging. Converging. Reverberating. Parallel after-discharge circuits. |
|
|
Neuroglia |
Small cells. Function in protections and support of neurons. Not excitable. Capable of mitosis. 6 types in total (4 types CNS, 2 type PNS) |
|
|
CNS - Four types of Neuroglia |
Astrocytes - Oligodendrocytes - Microglia - Ependymal - |
|
|
Astrocytes |
CNS Neuroglia Star shape. Forms blood brain barrier. Links neurons to blood vessels. Selectively chooses nutrients for neurons. |
|
|
Oligodendrocytes |
CNS Neuroglia Star shape. Smaller than astrocytes with fewer processes. Forms myelin sheath around axons of CNS neurons. Can myelinate several neurons (unlike shwann cells) |
|
|
Microglia |
CNS Neuroglia Immune cells of the brain. Small cells. Near blood vessels. Phagocytic role. Important for axon regeneration. |
|
|
Ependymal |
CNS Neuroglia |
