Volume 2 Something ToSettle The Nerves!! (An in depth look into the nervous system through recipes!) Marisa, Courtney, Nathan, Lindsey, Victoria, & Braxten
In this section: • Description of all three meninges • Description of the function of CSF • Description of the spinal cord • Structure and function of the brain stem • Structure and function of the cerebellum • Structure and functions of the diencephalon • Structure and function of the cerebral cortex• Description of the somatic sencory pathways in the CNS • Description of the somatic motor pathways in the CNS • Structure of spinal nerves • Description of the nerve plexuses • Description of the dermatomes and myotomes • Description of the cranial nerves • Difference between afferent and efferent nerves • Description of the autonomic nervous system • Purpose of the sympathetic nervous system • Purpose of the parasympathetic nervous system
Recipe: Central Nervous System Ingredients:1. Identify and describe function of all three Meninges.2. Describe function of CSF. 1. Where is it found? 2. Describe Circulation3. Describe structure and Function of Spinal Cord 1. Where is it 2. shape 3. Nerve roots Structure and function4. Structures and Functions of the Brain stem5. Structure and Function of the Cerebellum6. Structures and Functions of the Diencephalon(Thalmus, Hypothalmus)7. Structure and functions of Cerbral Cortex.8. Describe Somatic Sensory Pathways in the CNS9. Describe Somatic Motor Pathways in the CNS
(1) Directions continued: 3. Pour in the spinal cord which : - Two bulges, one in the cervical region and one in the lumbar region - Anterior median fissure (deeper) and posterior median sulcus (wider) are two deep grooves in the spinal cord 3. Reasons to cook with the spinal cord: Provides conduction to and from the brain Ascending tracts- conduct impulses up the cord to the brain Descending tracts-conduct impulses down the cord to the brain 1. It’s located in the spinal cavity and extends from the hole in the base of the skull (foramen magnum) to the first lumbar vertebra, the movable part of the vertebral column. Interneurons are located in the spinal cords gray matter cove (extends the length of the cord) 2. Oval-shaped cylinder that tapers from above downward 3. Fibers of dorsal nerve root Carry sensory information into the spinal canal Dorsal root ganglion- cell bodies of unipolar, sensory neurons make up a small region of gray matter in the dorsal nerve roots Fibers of ventral nerve root Carry motor information out of the spinal cord Cell bodies of multipolar, motor neurons are in the gray matter of the spinal cord
(1) Directions: 1. Add the Dura mater which is made of strong white fibrous tissue, acts as the outer layer of the meninges and also the inner peritoneum of the cranial bones Add the Arachnoid membrane which is cobweb like, and should be placed between the Dura mater and Pia mater Then add the Pia mater which is transparent, and adhere it to the outer surface of the brain and spinal cord 2. Pour on the Cerebrospinal fluid The purpose of this step is to protect the brain and spinal cord from injury by providing cushion. You can make the CSF by separating fluid from blood in choroid plexus Circulation route: formed be separation of fluid from blood in the choroid plexus into the ventricles of the brain, circulates through the ventricles and into the central canal and subarachnoid spaces and is absorbed back onto the blood.
(1) Directions continued: 4. Add the Brain Stem- The brainstem, like the spinal cord, preforms sensory, motor, and reflex functions. The spin thalamic tracts are important sensory tracts that pass through the brainstem and their way to the thalamus in the diencephalon. 5. Sprinkle in the Diencephalon (Thalamus, hypothalamus) Diencephalon literally means "between brain" is the part of the brain located between the cerebrum and the midbrain (mesencephalon). Although the diencephalon consists of several structures located around the third ventricle, the main ones are the thalamus and the hypothalamus. The diencephalon also includes the optic chiasma, the pineal body. 6. Beat in the Cerebellum. 1.Acts with the cerebral cortex to produce skilled movements by coordinating the activities of groups of muscles. 2. Helps control posture. Its functions below the level of consciousness to make movements smooth instead of jerky, steady instead of trembling, and efficient and coordinated instead of ineffective, awkward and uncoordinated. 3. Controls the skeletal muscles to maintain balance.
(1) Directions continued: 7. Structure and Function of the Cerebral Cortex (8) 8. Somatic Sensory Pathways in the CNS: For the cerebral cortex to perform its sensory functions, impulses must first be conducted to its sensory areas through neurons called sensory pathways. There are 3 pools of neurons, primary, secondary, and tertiary sensory neurons. 1. Primary neurons relay the impulses from the periphery (PNS) to the Central (CNS) 2. Secondary conduct from the brainstem to the thalamus. 3. Tertiary conduct from the thalamus to the post central gyrus of the parietal lobe. Mainly sensory pathways are “crossed pathways” which means impulses on the left side of the brain control actions on the right side of the body, and vice versa.
(1) 9. Somatic Motor Pathways in the CNS: - For the cortex to perform its motor functions impulses must be conducted from its motor areas to skeletal muscles by relays of neurons referred to as somatic motor pathways. - Motor pathways consist of motor neurons that conduct impulses from the central nervous system to somatic effectors, or skeletal muscles. Some pathways are extremely complex and not defined, others are simple and well established.
Recipe: Peripheral Nervous System Ingredients:1. Structure of Spinal Nerves2. Identify and Describe Nerve Plexuses3. Identify and Describe Dermatomes and Myotomes4. Identify and Describe Cranial Nerves5. Distinguish between Afferent and Efferent Nerves6. Describe structure and Function of Autonomic Nervous System7. Purpose of Sympathetic Nervous System8. Purpose of Parasympathic Nervous System
Directions:1. Arrange the Spinal Nerves as shown Cervical Plexus Left upper limb- Brachial Plexus Right upper limb- Brachial Plexus Thoracic Plexus Lumbar Plexus Lumbar Lumbar Plexus- Plexus- Right left lower limb lower limb (8) Sacral Plexus
2. Marinate the Nerve PlexusesFour major plexuses: 1. Cervical-supplies back of head, front of neck, upper part of shoulder, motor to numerous neck muscles spinal nerves c1-c4 2. Brachial- deep in the shoulder, passes from the ventral rami of spinal nerves C4- T1, beneath the clavicle, ant toward the upper arm 3. Lumbar- formed by the intermingling of fibers from the first four lumber nerves, located in the lumbar region of the back, provides many branches supplying the thigh and leg 4. Sacral-fibers from the L4and L5, lies in the pelvic cavity
(7)3. Layer the Dermatomes and Myotomes to taste:- Dermatomes- skin surface supplied by sensory fibers “skin section”- Myotomes- skeletal muscle or group of muscles that receives motor axons from agiven spinal nerve.
(1) Directions: 4. Add the Cranial Nerves - Twelve pairs of cranial nerves connect to the undersurface of the brain mostly on the brain stem. Cranial nerves pass trough small holes in the cranial cavity of the skull, allowing them to extend to or from their peripheral destinations. (8)
(1) Directions: 5. Mix in the Afferent and Efferent Nerves Afferent Nerves (Carry Towards): The afferent division of the nervous system consists of all the incoming sensory or afferent pathways. Efferent Nerves (Carry Away): The efferent division of the nervous system consists of all the outgoing motor or efferent pathways. 6. Describe structure and function of autonomic nervous system: Left Lateral Pectoral Right Lateral Pectoral CN 10 Vegus (8) (8)
(1) Directions: 7. Identify the purpose of Sympathetic Nervous System - Part of the autonomic nervous system; ganglia are connected to the thoracic and lumbar regions of the spinal cord; functions in “fight-or-flight” response. 8. Understand the purpose of Sympathetic Nervous System - Part of the autonomic nervous system; ganglia are connected to the brainstem and the sacral segments of the spinal cord; controls many autonomic effectors under normal (rest and repair) conditions.