BIOL 2401 Chapter 12-14 Study Guide

• Three general functions of the nervous system are

  Collect information (through receptors)Process and evaluate information Initiate response to information (effectors)
• Describe the structural components included in the CNS and those in the PNS

  CNS: Brain and spinal cord; PNS: Nerves and ganglia
• Explain the functional organization of the nervous system (Sensory Nervous System)

  Two components: somatic sensory (detects stimuli we can consciously perceive; includes receptors related to five senses and proprioceptors) and visceral sensory component (detects stimuli we typically do not consciously perceive; stretch of an organ wall or chemical composition in blood)
• Explain the functional organization of the nervous system (Motor Nervous System)

  Somatic motor (transmits motor output from the CNS to skeletal muscle -- only muscle under voluntary control); Automatic motor (innervates and regulates the other types of effectors to cardiac muscle, smooth muscle, and glands
• List and explain the five distinguishing features common to all neurons

  Excitability: responsiveness to stimuli; Conductivity: propagation of electrical signals/changes; Secretion: release neurotransmitters in response to conductive activity; Extreme Longevity: most formed during fetal development and last until elderly age; Amitotic: most neurons lose ability to form new cells through cell division
• Which anatomic features are common to most neurons?

  Cell body (soma), perikaryon, dendrites, axon, axon collaterals, myelin sheaths, cytoskeleton
• Accumulation of stimuli occurring in neurons or muscle cells

  Summation
• Multiple presynaptic neurons release neurotransmitters at various locations onto the receptive segment, generating EPSPs , IPSPs, or both in the postsynaptic neurons.

  Spatial summation
• Single presynaptic neuron repeatedly releasees neurotransmitter to produce either multiple EPSPs or IPSPs in the postsynaptic neuron at the same location within a very short period of time.

  Temporal summation
• Describe the general regions of the brain.

  - Cerebrum: L & R hemisphere- Diencephalon: Epithalamus, thalamus, hypothalamus- Brainstem: midbrain, pons, and medulla oblongata- Cerebellum: inferior to cerebrum
• General composition, function, and distribution of gray matter throughout the CNS

  - Cell bodies and dendrites of neurons that compose it- Cortex, Nucleus or center- Serve as an integrating and processing area
• General composition, function, and distribution of white matter throughout the CNS

  - Bundles from myelinated axons (tracts) that compose it- Funiculi and white commissures- Relay nerve signals/information to different regions of brain and spinal cord and b/w the brain and body
• Structure and location of cranial meninges

  - Innermost; thin layer of delicate areolar CT = Pia Mater- External to pia mater/middle layer; delicate web or collagen and elastic fibers = Arachnoid Mater/Membrane- Outer layer; Dense irreg CT (meningeal and periosteal layer) = Dura Mater
• Space immediately deep to the arachnoid mater, contains cerebrospinal fluid (CSF)

  Subarachnoid Space
• Blood-filled spaces that separate the meningeal layer and periosteal layer


  Dural venous sinuses
• Space that separates dura mater and bones of skull

  Epidural space
• Space that separates arachnoid mater and dura mater

  Subdural space
• Anatomy of ventricles


  Cavities/expansions within brain that are derived from the neural canal; lined with ependymal cells and contain CSF
• Lateral Ventricles (Location)


  Within cerebrum, separated by the septum pellucidum
• Third ventricle


  within diencephalon
• Fourth ventricle

  Location between the cerebellum and brainstem (pons and medulla oblongata)
• Three functions of CSF

  Buoyancy: brain floats within CSF; Protection: liquid cushion to protect the brain; Environmental Stability: transports nutrients and chemical messengers to the brain and removes waste products from the brain
• How does the blood-brain barrier protect the brain?


  Helps prevent exposure of neurons in the brain to drugs, waste products in blood, and variations in levels of normal substances that could aversively affect brain function.
• Explain the functions of the prefrontal cortex

  Higher intellectual functions (complex thought, judgement, expression of personality, planning future behaviors)
• Why does the prefrontal cortex function differently in a teenage versus an adult?

  This area continues to develop into 20s
• Describe the main functions of the Wernicke area

  Recognizing, understanding, and comprehending spoken or written language. ("W" for Wernicke = "W" for word)
• What are the functions of the cerebellum?

  Ensures muscle activity follow correct pattern, stores memories of previously learned movements, regulates activity along voluntary and involuntary motor paths, ensures smoothness of movements, maintains equilibrium and posture
• Identify the parts of the brain involved in short term memory

  Hippocampus and amygdala
• Identify the parts of the brain involved in long-term memory

  Corresponding association areas (auditory association cortex), premotor cortex, cerebellum
• Names and locations of the 12 pairs of cranial nervesCN I CN II CN IIICN IV CN V CN VI CN VII CN VIII CN IX CN X CN XI CN XII

  - Olfactory (olfactory epithelium of nasal cavity)- Optic (retina of eye)- Oculomotor (oculomotor and Ediner Westphal nuclei w/in midbrain)- Trochlear (trochlear nucleus w/in midbrain)- Trigeminal (nuclei in pons)- Abducens (pontine (abducens) nucleus in pons)- Facial (nuclei in pons)- Vestibulocochlear (vestibular apparatus and cochlear of inner ear)- Glossopharyngeal (sensory axons located --> taste buds, mucosa of posterior 1/3 of tongue; motor axons --> nuclei in medulla oblongata)-Vagus (motor nuclei in medulla oblongata)- Accessory (nucleus in medulla oblongata and spinal cord)- Hypoglossal (hypoglossal nucleus in medulla oblongata)
• What is the mnemonic for the cranial nerves?

  Oh Once One Takes The Anatomy Final Very Good Vacations Are Heavenly
• Functions of CNCN I CN II CN IIICN IV CN V CN VI CN VII CN VIII CN IX CN X CN XI CN XII

  - Smell- Vision- Eye movement (extrinsic eye mm.; lens shape changes; pupil constriction)- Contracts superior oblique m. to move eye inferiorly and laterally- Senses touch, temp, pain; innervates mm. of mastication- Eye abduction (moves eye laterally)- Taste sensations, innervate face muscles, increases secretions of lacrimal gland of eye and submandibular/sublingual salivary glands- Equilibrium and hearing- Swallowing, secretion of parotid salivary gland- Relays visceral & sensory information, swallowing and speech, controls smooth muscles/abdominal organs/cardiac muscle- Innervating pharynx muscles; trapezius and sternocleidomastoid (SCM) muscles- Tongue movement
• Two primary functions of the spinal cord and spinal nerves are

  Provide structural and functional link b/w the brain, torso, and limbs; spinal reflexes
• General structure of the spinal cord and its four anatomic subdivisions

  - Roughly cylindrical NS structure that extends through the vertebral column to the inferior border of the L1 vertebra.- Cervical (continuous with medulla oblongata), Thoracic, Lumbar, and Sacral
• Explain the naming of the 31 pairs of spinal nerves.

  Typically identified by first letter of the spinal part where it attaches, followed by a number.(8 cervical nerves (C1-C8), 12 thoracic (T1-T12), Lumbar (L1-L5), Sacral (S1-S5, Coccygeal (Co1)
• General description of a spinal nerve and its composition.


  - Organ composed of cablelike bundle of axons; contain epineurium (around nerve), perineurium (around fascicle), endoneurium (around axon)- Rootlets = roots, post. root = sensory neurons, ant. root = motor neurons; spinal nerves form where root joins
• Explain the relationship of the spinal cord and spinal nerves to the vertebral column.

  Vertebral column = bony framework that houses the spinal cord; spinal cord extends through stacked vertebral foramina; each spinal nerve exits the vertebral column through intervertebral foramen
• Location and function of spinal cord meninges

  Located: Within the vertebral canal(Pia mater, arachnoid mater, and dura mater (innermost to outermost))Function: Protect and encapsulate the spinal cord
• Compare and contrast the three spaces associated with the spinal cord meninges.

  - Pia mater: delicate; meshlike; elastic and collagen fibers- Arachnoid mater: delicate; web; elastic and collagen fibers- Dura mater: dense irregular CT; subdural and epidural space
• Bundle of axons in the CNS; white matter on each side of the cord; myelinated axons that have a common origin, destination, and function

  Tract(s)