Anatomy Week 2 Flashcards
What do each of the two anatomical divisions of the nervous system consist of?
- CNS = Brain and Spinal Cord
- PNS:
- Cranial/Spinal Nerves
- Ganglia
- Autonomics
- Enteric Plexuses
- Sensory Receptors
Describe the 3 functional levels of Central Nervous System Organization:
- Sensory (Input) = Afferent neurons
- Integrative (Control) = Interneurons
- Motor (Output) = Efferent neurons
Describe the 3 functional levels of Peripheral Nervous System Organization:
- Somatic Nervous System
- Autonomic Nervous System
- Enteric Nervous System
Motor neurons of the SNS are _______ while motor neurons of the ANS are ______.
- Voluntary
2. Involuntary
Sensory neurons of the SNS receive input from _______, while sensory neurons of the ANS receive input from _______.
- Outside the Body
2. The Viscera (Internal Organs)
What are the 2 divisions of the ANS?
- Sympathetic: Fight or Flight
2. Parasympathetic: Rest and Digest
The basic structural unit of the Nervous System is the _______.
Neuron
Describe the 2 main components of a neuron:
- Cell Body:
- Nucleus
- Nissl Bodies: Clusters of rER - Nerve Fibers:
- Dendrites: Input portion
- Axons: Output portion
What cells are responsible for myelination in the Somatic and Peripheral Nervous Systems respectively?
- Oligodendrocytes
2. Schwann Cells
Describe the 3 different structural types of neurons:
- Multipolar Neurons: Multiple dendrites receiving input, one axon providing output
- Unipolar Neurons: One dendrite and one axon (sensory and often somatic in nature)
- Bipolar Neurons: One dendrite and one axon (associated with special senses)
Differentiate between Ganglia and Nuclei:
- BOTH are collection of neuronal cell bodies.
2. Ganglia are located in the PNS while Nuclei are located in the CNS.
Differentiate between Nerves and Tracts:
- BOTH are bundles of neuronal axons.
2. Nerves are located in the PNS while Tracts are located in the CNS.
Differentiate between White Matter and Grey Matter:
White Matter is primarily composed of white, myelinated axons, while Grey Matter is primarily composed of neuronal cell bodies, dendrites, and un-myelinated axons.
Where are white matter and grey matter located, relative to one another, in the brain and spinal cord respectively?
- In the Brain:
- White Matter INSIDE
- Grey Matter OUTSIDE - In the Spinal Cord:
- White Matter OUTSIDE
- Grey Matter INSIDE (butterfly shape)
Describe the protective coverings of the spinal cord:
- The Meninges: (3 layers)
- Dura Mater (Outer layer)
- Arachnoid Mater (Middle layer)
- Pia Mater (Inner layer)
What is the Epidural Space? What is the SubDural Space?
- The space between the Dura Mater of the spinal cord and the wall of the vertebral canal.
- The space between the Dura Mater and the Arachnoid Mater.
The spinal cord meninges are continuous with _____________.
The meninges of the brain
Describe the Subarachnoid Space? What is special about it?
- The space between the Arachnoid Mater and the Pia Mater.
2. It is filled with cerebrospinal fluid (CSF).
CSF acts as a ______ for the spinal cord.
Shock absorber
The spinal cord extends from the _______ to the ______. It gives rise to _____ pairs of spinal nerves.
- Foramen Magnum of the skull
- L-2 vertebrae
- 31
What are MIXED nerves?
Nerves that have both motor and sensory components
The spinal cord is not uniform in diameter. It has an enlarged _____ region which supplies _______, and it has an enlarged _____ region which supplies _______.
- Cervical
- Upper limbs
- Lumbar
- Lower limbs
The inferior end of the spinal cord proper is called the _______, while the origin of the spinal nerves that EXIT from that inferior end is called the _______.
- Conus Medullaris (at L-1 or L-2)
2. Cauda Equina
What is the filum terminale?
The connective tissue that extends from the conus medullaris to the coccyx