Module 5 - Introduction to the neuroanatomy of the CNS and PNS - Original slides Flashcards
The nervous system is divided into two major subdivisions: the ____________________, that consists of the _________ and the ____________, and the __________________, the most obvious components of which are the_______________and _______________.
The nervous system is divided into two major subdivisions: the central nervous system (CNS), that consists of the brain and the spinal cord, and the peripheral nervous system (PNS), the most obvious components of which are the spinal and cranial nerves.
The functional unit of both the CNS and PNS is the ______________. Neurons possess: ______________ that contains the _________ and ______________ and have projection either carrying electrical signals towards (___________) or away (___________) from the ______. Neurons communicate with each other via _________, with output at ___________and inputs onto __________.
The functional unit of both the CNS and PNS is the neuron (or nerve cell). Neurons possess: a soma (or cell body) that contains the nucleus of the cell and other cellular machinery and have projection either carrying electrical signals towards (dendrites) or away (an axon) from the soma. Neurons communicate with each other via synapses, with output at axon terminals and inputs onto dendrites.
Many axons are covered in ______, formed by ____________. In the CNS the cells are ______________; in the PNS they are called _________. Myelin provides electrical insulation allowing the electrical signal in the cell body to reach the axon terminal (and do so quickly).
Many axons are covered in myelin, formed by glial cells. In the CNS the cells are oligodendrocytes; in the PNS they are called Schwann cells. Myelin provides electrical insulation allowing the electrical signal in the cell body to reach the axon terminal (and do so quickly).
The relative amount of myelin within a region of the nervous system is indicative of the presence of axons. Regions with a lot of myelin indicate collection of fibres and, because of their appearance in dissected brains, came to be called __________________ In contrast, regions with little myelin generally indicate a greater density of somas, and came to be called ___________.
The relative amount of myelin within a region of the nervous system is indicative of the presence of axons. Regions with a lot of myelin indicate collection of fibres and, because of their appearance in dissected brains, came to be called white matter. In contrast, regions with little myelin generally indicate a greater density of somas, and came to be called gray matter.
In the cerebral hemispheres gray matter is found on the ___________of the brain with white matter ____________.
In the spinal cord, gray matter is found _____________ and is ___________ by white matter.
in the cerebral hemispheres gray matter is found on the surface (cortex) of the brain with white matter beneath.
In the spinal cord, gray matter is found centrally and is surrounded by white matter.
A collection of neurons with similar structure and function are called
1- _____________ (plural = ?) - within …..
2- _____________ (plural = ?) outside …..
A collection of neurons with similar structure and function are called
1- Nucleus (plural = nuclei) - within the CNS (but you can contain neurons that are part of the PNS)
2- Ganglion (plural = ganglia) outside the CNS and part of the PNS
IDENTIFY.
The outer surface (cortex) of both the cerebrum and the cerebellum can be thought of as sheets of tissue, but the sheets are extensively folded (_____________) allowing increased surface area within a three-dimensional space. In the cerebrum, the folds form ________(______ ________) separated by _______ (______ _______). In the cerebellum, the corresponding terms are ____________ and __________.
The outer surface (cortex) of both the cerebrum and the cerebellum can be thought of as sheets of tissue, but the sheets are extensively folded (convolutions) allowing increased surface area within a three-dimensional space. In the cerebrum, the folds form gyri (singular gyrus) separated by sulci (singular sulcus). In the cerebellum, the corresponding terms are folia and fissures.
IDENTIFY.
IDENTIFY.
Cerebrum
Cerebellum
Spinal cord
Brainstem
Medulla
Pons
Midbrain
Diencephalon
Thalamus
Hypothalamus
IDENTIFY.
Each cerebral hemisphere is subdivided into lobes. Visible laterally is: ____________that is separated from the ____________ by the ______________. The ______________ is inferior to the ___________ and portions of the __________and largely (but not completely) separated by the __________________(________________). Note that there is not always a sulcus that clearly or completely separates the lobes.
Each cerebral hemisphere is subdivided into lobes. Visible laterally is: the frontal lobe that is separated from the parietal lobe by the central sulcus (of Rolando). The temporal lobe is inferior to the frontal lobe and portions of the parietal lobe and largely (but not completely) separated by the Sylvian fissure (or lateral sulcus). Note that there is not always a sulcus that clearly or completely separates the lobes.
On the medial surface there is a sulcus separating the parietal and occipital lobe. Sometimes anatomy is easy and obvious! This sulcus is called the ______________________.
But there is another lobe, more recently defined and more functionally than anatomically, _____________
on the medial surface there is a sulcus separating the parietal and occipital lobe. Sometimes anatomy is easy and obvious! This sulcus is called the parieto-occipital sulcus.
But there is another lobe, more recently defined and more functionally than anatomically, the limbic lobe.
The ______________ is a large (in fact, the largest) collection of white matter that connects the cerebral hemispheres. If you were to place your finger into the medial longitudinal fissure your finger tips would touch the __________.
The corpus callosum is a large (in fact, the largest) collection of white matter that connects the cerebral hemispheres. If you were to place your finger into the medial longitudinal fissure your finger tips would touch the corpus callosum.
The ____________ or __________, covered by _________ of frontal, parietal and temporal lobes. Consists of __________.
The insular lobe or insula, covered by opercula of frontal, parietal and temporal lobes. Consists of long and short gyri.
IDENTIFY.
IDENTIFY.
The spinal cord gives rise to ____________________that are named in relation to the adjacent vertebrae (cervical, thoracic, lumbar, sacral) through which they exit (intervertebral foramina). There are two regions where the spinal cord is expanded, ______________________________. These regions are enlarged because at these levels the spinal nerves, that innervate the upper or lower limb, contain a lot of fibers.
The spinal cord gives rise to 31 pairs of spinal nerves that are named in relation to the adjacent vertebrae (cervical, thoracic, lumbar, sacral) through which they exit (intervertebral foramina). There are two regions where the spinal cord is expanded, the cervical and lumbar enlargements. These regions are enlarged because at these levels the spinal nerves, that innervate the upper or lower limb, contain a lot of fibers.