Anatomy and histology of Nervous System Flashcards
Through what fibres does the body sense internal and external factors?
Peripheral nerve fibres
What does the term afferent mean?
Senses are passed within the nerve fibres centrally to your brain, either directly or via the sponal cord
What does the term efferent mean?
When the brain chooses if impulses are to be sent down peripheral nerve fibres, either directly or via the spinal cord to bring about an appropriate motor response
What can the nervous system be partitioned anatomically into?
Central
Peripheral
What does the Peripheral nervous system consist of?
12 pairs of cranial nerves
31 pairs of spinal nerves and their branches
What does the CNA contain?
Brain
Spinal cord
What can the nervous system be partitioned into functionally?
Somatic
Autonomic
What is the definition of the somatic nervous system and what does it supply?
Senses and responds to the external environment
Supplies almost everything other than the organs contained within the body cavities
What does the somatic nervous system contain?
Sensory nerves from the skin, bones and joints
Motor nerves to skeletal (striated) muscle
Is the somatic nervous system voluntary?
yes
What does the autonomic nervous system mean?
Senses and responds to the internal environment
Is the autonomic nervous system voluntary or involuntary?
Involuntary
What is the control centre of the nervous system?
The brain
What are the components of the right cerebral hemisphere of the brain?
Gyrus
Sulcus
Spinal cord
Brain stem
What are the components of the brain stem?
Midbrain
Pons
Medulla oblongata
What is the foramina?
Through which cranial nerves and blood vessels enter/exit the skull
Name the cranial nerves?
(1-11)
ooo to touch and feel a virgins girl’s vagina ah(a)!!
Olfactory Optic Oculomotor Troclhear Trigeminal Abducens Facial Vestibulocochlear Glossopharyngeal Vagus Accessory Hypoglossal
What does the grey matter consist of in the CNS?
Neurons
Cell processes
Synapses
Support cells
What is the white matter in the medullary centre?
Axons (most myelinated)
Support cells
What is the main white matter fibre tract between the spinal cord and the cerebral hemispheres called?
What does it consist of?
The internal capsule
Caudate nucleus
Thalamus
Putamen
What does the spinal white matter consist of?
Axons
Myelin sheaths
Blood vessels
What is a neuropil?
A mat of neuronal and glial cell processes that occupies much of the grey matter
What does the precentral gyrus do?
How is it organized?
Initiates movement
Somatotopically organised
What is somatotropic organization?
The body is mapped onto the cortex, with each part of the cortex controlling a particular part of the body
What side of the body does the right cortex control?
Muscles on the left side of the body
What cell is the myelin sheeth (electrical insulator) produced by?
Schwann cell
What does one spinal nerve contribute towards?
Efferents to several peripheral nerves
What does one peripheral nerve send?
Afferents to several spinal nerves
What is a dermatome?
The area of skin supplied by the senory fibres in a given segmental somatic nerve
Are there any nerve cell bodies present in a peripheral nerve?
No
What is part of the sympathetic nervous system in the autonomic nervous system?
Heart Arterioles Skin Lungs Gut Pupils Liver
What does the parasympathetic nervous system not supply that the sympathetic does?
Skin and arterioles
What are the sympathetic nerves and components of the system?
Spinal nerve
Thoraco-lumbar outflow
Sympathetic chain
Splanchnic nerves
What are the parasympathetic nerves and components of the system?
Cranial nerves 3, 7, 9 and 10 (10-the vagus nerve)
Cranio0sacral outflow
Sacral spinal nerves
What are the two blood vessels that supply blood to the brain?
Vertebral Arteries
Internal Carotid Arteries
Where does the right vertebral artery join the cervical part of the spine?
C6
What do the dural venous sinuses do?
Drain deoxygenated blood from the brain
Where do the dural venous sinuses drain into?
The internal jugular vein
What is the meninges and what are their three layers?
Three layers of connective tissue membranes that cover the CNS
Pia mater
Arachnoid mater
Dura mater
Where is the cerebrospinal-spinal fluid secreted from?
Specialized structure within the ventricular system of the brain called the choroid plexus
Where does the cerebrospinal-spinal fluid circulate?
Around the brain and spinal cord from the 4 ventricles to the subarachnoid
How is the cerebra-spinal fluid reabsorbed?
Reabsorbed into the dural venous sinuses by specialised structures called arachnoid granulations
What does cerebrospinal-spinal fluid surround the brain with?
Subarachnoid Space
In neuronal morphology what is multipolar, bipolar and pseudounipolar?
Multipolar- Most common, many dendrites one axon
Bipolar- One dendrite, one axon
Pseudounipolar- Short process gives rise to axon in both directions
How many layers of the cerebral cortex?
6
How many layers in the cerebellar cortex?
3
How many types of glial cells are there?
4
What are astrocytes?
Many numerous processes
Roles in support, maintaining the blood-brain barrier
Environmental homeostasis
No connective tissue in the CNS
What are neurons?
Receive information via synapses
Integrate the information
Transmit electrical impulses to another neuron or effector cell
Most are multipolar
What are the four types of glial cells?
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
What are oligodendrocytes?
Produce myelin in the CNS - NOT in the PNS
What are microglia?
Cells of similar lineage to macrophages (ie. hemopoeitic origin)
Immune monitoring and antigen presentation
What are ependymal cells?
Cuboidal/columnar epithelium that lines the ventricles
