Exam 1 NS Design Flashcards
three thing to consider in the basic design of the adult nervous system
~Cells of the Nervous System
~Divisions of the Nervous System
~Organizing Principles
two types of cells in the nervous system
~Neurons
~Neuroglia
Neurons have _ parts:
3
Cell body, dendrites, single axon
Neurons can also be called
Nerve cell
~is the principal cell of the nervous system
Cell bodies are
~the central part of the neuron
~where the electrical integration occurs
Dendrites are
~there any many highly branching dendrites
~forms the input into the cell body
Axons are
~the part that connects to the other neurons through a synapse
Neuroglia are also called
supporting cells
Neuroglia (details)
~come in several forms
~have many different functions (the formation of myelin)
Communication between Neurons is possible because of
synapses
Synapses form
the connection between neurons and between neuron and the cells of other tissues
Synapses are composed of
~a presynaptic neuron whose membrane contains neurotransmitters in synaptic vesicles
~membranes of a postsynaptic neuron
Neurotransmitters
~are released from the presynaptic membrane and diffuse through the synaptic cleft to act on receptors on the membrane of the postsynaptic neuron
~binding of the neurotransmitter to the receptor produces electrical charges- action potentials
Anatomically, the nervous system is divided into
CNS and PNS
Anatomically, the CNS is divided into
Brain and spinal cord
Anatomically, the PNS is divided into
Spinal nerves and cranial nerves
How many spinal nerves are there?
31 paired
How many cranial nerves are there?
12 paired
Functionally, the nervous system divided is divided into
somatic and autonomic
Somatic (details)
~innervates the skin
~voluntary muscles of the body wall and limbs
Autonomic (details)
~innervates smooth muscle, cardiac muscle, and glandular tissue
The Autonomic is divided into
sympathetic and parasympathetic
Organizing Principles of Nervous System (6)
~Regions ~Connective tissue membranes ~Ventricles ~Directions and planes ~White and gray matter ~Fiber organization
Regions of the Brain (4)
~Cerebrum
~Diencephalon
~Cerebellum
~Brainstem
The cerebrum is composed of ______ and can be divided of (2)
~composed of 2 cerebral hemispheres
~divided into the superficial cerebral cortex and the deeper basal ganglia
The diencephalon is located
deep within the cerebrum
The diencephalon is composed of
thalamus and hypothalamus
The brainstem is composted of (3)
~upper midbrain
~middle pons
~lower medulla
what is another name for upper midbrain?
mesencephalon
The cerebellum is located
along the dorsal aspect of the brainstem
The layers of connective tissues that surround the CNS are (3)
~Dura mater
~Arachnoid mater
~Pia mater
Dura mater (details)
the tough outer layer
Arachnoid mater (details)
the weblike middle layer
Pia mater (details)
the thin inner layer which hugs the brain and spinal cord tissue
Subarachnoid space (details)
~between the arachnoid mater and the pia mater
~filled with fluid called cerebrospinal fluid
Ventricles (how many)
There are 4 cavities in the brain.
~2 lateral ventricles (left and right) which project into each cerebral hemispheres
~3rd ventricle between the thalami which separates the two thalami
~4th ventricle in the dorsum of the brainstem, between the brainstem and the cerebellum
Ventricles (connections)
~2 interventricular foramena- connecting the lateral to the 3rd ventricle
~cerebral aqueduct- connects the 3rd and 4th ventricle
Ventricle (function)
~filled with CSF, which communicates between the ventricles and between the 4th ventricle and the subarachnoid space
~also communicates with the fluid in the extracellular space of the brain and spinal cord
~involved in eliminating waste products
~providing electrolytes of the extracellular
~limited extent- nutrition to CNS
Three basic patterns of transverse sections
~Frontal or coronal
~Sagittal (mid sagittal or parasagittal)
~Horizontal
*oblique is between the planes
Why is directional terminology different from cerebrum and spinal cord?
~the human brain is on the neural axis, which is bent in transition between the brainstem and cerebrum
What are the directional terminology for the spinal cord?
~rostral or superior
~caudal or inferior
~ventral or anterior
~dorsal or posterior
What are the directional terminology for the cerebrum?
~Rostral or anterior or frontal
~Caudal or posterior or occipital
~Dorsal or superior
~Ventral or inferior
Gray Matter
~composed of neuron cell bodies and dendritic field
~in cerebrum and cerebellum, found both along the outside and deep within these structures
~in spinal cord, located only deep within
~in brainstem, located throughout and is intermixes with white matter
Gray matter- cortex
outer rim of the cortex
Gray matter- nucleus
~deep gray matter; group of cell bodies
~sometimes called gray or cell columns
Gray matter- ganglia
groups of cell bodies in the peripheral nervous system
Basal Ganglion
basal nuclei of the cerebrum
White matter
~surrounds the deep gray matter
~composed of groups of myelinated axons
White matter- tracts
a collection of axon within the CNS with the same termination and function
Other types of white matter
~white columns, peduncles, pyramids, fasciculus, funiculus, lemniscus or capsule
~cerebral peduncle, internal capsule, dorsal white columns, the pyramids or the medulla and the lateral funiculus
Commissure
Axons that cross midline from one area of CNS to the equivalent area on the opposite side
Decussation
Axons that cross midline from one area of the CNS to a different area on the opposite side
Afferent
~towards the center
~sensory input into the CNS and alternatively fibers going towards a nuclear area
Efferent
~outward from the center
~motor fibers leaving the CNS and alternatively fibers leaving a nuclear area
