Nervous System Unit Test Flashcards
What is the Afferent Neuron?
Neuron that carries ELECTRICAL impulses TOWARDS the CNS (Integration Center)
What is the Efferent Neuron?
Also known as Motor Neurons, they carry ELECTRICAL impulses AWAY from the CNS towards a muscle to contract
What is the Association Neuron?
Also known as Inter-neurons, these neurons RECEIVE messages from Afferent Neurons and link them to the Efferent/Motor Neurons (Located within the integration center)
What is a Neuron?
The messengers of the Nervous System, they use Electrical and Chemical (Synapse only) signals to transmit messages to and from the body. THE TYPE OF NERVE TISSUE THAT DOES NOT DIVIDE (Amitotic)
What is Neuroglia?
The supporting cells in the CNS, being lumped together. Neuroglia literally translates to “Nerve Glue”, all other parts of the nervous system that aren’t neurons
What are Neurotransmitters?
Chemical messengers (different from Neurons, being electrical messengers)
What is the CNS?
The brain and spinal cord, short for “Central Nervous System”
What is a Synapse?
Junction point between two neurons (chemical)
Define: Stimuli
Change in exterior environment that provokes a bodily response
What is Somatic Reflex?
Skeletal muscles involved in reflex movements
What is Autonomic Reflex?
Any and all other muscles besides skeletal muscles involved, happening without the use of the brain 24/7
What is the PNS?
Everything outside of the Brain and Spinal cord, short for Peripheral Nervous System
What is an Axon?
Part of a neuron that conducts and directs impulses AWAY from the cell body and OUTPUTS instructions (Efferent)
What is a Dendrite?
Part of a neuron that conducts and directs impulses TOWARDS the cell body and RECEIVES stimuli (Afferent)
What are the 4 Major regions of the brain?
- Cerebrum - Central Hemisphere
- Diencephalon - Within the Cerebrum
- Brain Stem
- Cerebellum - Mini Cerebrum
What is the Cerebrum?
The two primary and biggest sides of the brain, making a boxing glove shape when looking forward. It has a deep grove running down the middle to separate, and a wrinkled appearance, consisting of many peaks and valleys
What are Gyri?
Plural of Gyrus, elevated parts of the brain, composed of gray matter and surrounded by Sulcus (remember, Gyri are peaks, Sulci/Fissures are valleys)
What are Fissures?
Also known as “deep sulci,” these are deep “V” shaped grooves within the brain, separating the brain into lobes (remember, Fissures are valleys, Gyri are peaks)
What are Sulci?
Plural for Sulcus, shallow “U” shaped grooves within the brain, being more abundant than Fissures and surrounding Gyri (remember, Sulci are valleys, Gyri are peaks)
What are the 4 brain lobes and what do they control?
A. Occipital Lobe - Visual control area
B. Temporal Lobe - Auditory control area, above the ears
C. - Frontal Lobe - Motor control area, conscious movement of skeletal muscles
* Broca’s Area - Speech
control area found on
one hemisphere
D. Parietal Lobe - Somatic sensory area, receiving stimuli notifications from skin receptors/proprioceptors
What are additional parts of the Cerebrum to know?
- General Speech Area - Found at junction of the lobes and allows sounding words
- Gray Matter - Neuron cell bodies (surface of brain ridges)
- White Matter - Nerve fiber tracts deep in Cerebral Hemisphere (within/body of brain ridges)
- Cortex (Gray/White matter) - Where neurons are found
What are the Meninges?
The three “Maters”
- Dura Mater - “Hard Mother”, tough outermost layer, enclosing the brain and spinal cord
- Arachnoid Mater - Thin, middle layer of the CNS with web-like extensions
- Pia Mater - “Gentle Mother”, most internal layer of the Meninges, clinging to and holding the brain intact
Where does the Spinal Cord begin and extend to?
It begins at the Medulla (brain stem), and extends from the Foramen Magnum of the skull to the first or second Lumbar Vertebrae
What is the function of the Spinal Cord?
- It provides a two-way connection between the body and the brain (afferent and efferent)
- Works with the PNS, equipped with spinal nerves
How do spinal nerves work? How many are there?
Spinal nerves exit between each vertebra (31) in order to communicate with the body, making 31 total spinal nerves
They carry electrical impulses from the brain towards the skeletal muscles and organs via. spinal cord
What is the Cauda Equina?
The collection of spinal nerves at the inferior end of the spine (1st or 2nd Lumbar Vertebrae)