Exam 3 Anatomy Study Guide
Chapter 13: Neural Tissue:
1. How are neurons and neuroglia different? Neurons: nerve cells are responsible for the transfer and processing of information in the nervous system consist of soma, axon, and dendrites Neuroglia: supporting cells, protect the neuron 2. What types of neuroglia are in the CNS and PNS and what are the specific functions of each? PNS: a. Satellite Cells: regulates oxygen and carbon dioxide nutrient, and neurotransmitter levels around neurons in ganglia b. Schwann Cells: responsible for myelination of peripheral axons, and participate in repair process after injury CNS: a. Oligodendrocytes: provide structural framework, myelinate CNS axons b. Astrocytes: maintain blood-brain barrier, provide structural support, regulate ion nutrient c. Microglia: remove cell debris, wastes, and pathogens by phagocytosis d. Ependymal cells: line ventricles (brain), and central canal (spinal cord), assist in producing, circulating and monitoring cerebrospinal fluid 3. What are the components (structure) of a neuron, why cant they reproduce and what are nissl bodies? Dendrites: stimulated by environmental changes or the activities of other cells Cell body: contains the nucleus, mitochondria, ribosomes, and other organelles and inclusions Axon: conducts nerve impulse (action potential) toward synaptic terminals Nissl bodies: create gray matter Neurons cannot reproduce because they lack centrosomes! *4. What are the 5 types of synapses 5. How are neurons classified? Know the 4 structural and 3 functional classifications a. classified based on structure or function Structural: based on placement of the cell body, based on number of processes extending from the cell body -anaxonic neuron -bipolar neuron -pseudounipolar neuron -multipolar neuron Functional: -sensory: sends information from receptors in the PNS to the CNS -motor: sends information from the CNS to effectors in the periphery or organs -interneurons: situated between the motor and sensory neurons, analyze sensory input and coordinate motor output, can be excitatory or inhibitory *6. How do neurons regenerate? What helps and what regenerates? Schwann cells grow into the cut area and axons begin to grow into the Schwann cells 7. Nerve impulses, what it means by excitability, action potential, and threshold level nerve impulse- action potential of a nerve action potential- due to the exchange of ions across the membrane threshold level- the amount of stimuli required to create the action potential excitability- ability to conduct the impulse
8. What does the speed of a nerve impulse depend on? -presence of a myelin sheath: fast impulse -lack of a myelin sheath: slow impulse -axon with a large diameter- fast impulse -axon with a small diameter – slow impulse 9. What is a synapse and what are the differences between nonvesicular and vesicular synapses? synapse: junction between two neurons nonvesicular synapses: involve the flow of ions impulses can be conveyed in any direction vesicular synapses (chemical synapses): involve a neurotransmitter gen 10. The 5 neuronal pools and examples: neurons can be organized into smaller groups called neuronal pools neuronal pools are identified by their neural circuitry such as: a. divergence: spread of info from one neuron to several neurons b. convergence: info going from several neurons to a single neuron ex: nerve that control our diaphragm c. serial processing: information going from one neuron to the next in a sequence ex: going to one part of the brain to another part, ect. d. Parallel processing: several neurons are processing the info at the same time ex: stepping on a nail and shouting “ouch” and dancing at the same time e. Reverberation: collateral axons extend back toward the origin of the impulse to cause an enhancement or continuation of impulse ex: generating new memories
Chapter 14:
1) What are the four nerve plexus & what components belong to each?
Cervical plexus -> consists of cutaneous & muscular branches Brachial plexus -> superior, middle, inferior trunk, they all merge to form cords Lumbar plexus -> Nerves Sacral plexus -> trunks & nerves
2) What are the four branches of the spinal nerves and what do they innervate?
White ramus 2 rami communicates • What are the auditory ossicles, which one is attached to the tympanic membrane, which one is attached to the oval window and which is in the middle? • What is in the membranous and bony labyrinths? • Where are the ampulae and relative to the cristae? • Where are the RECEPTORS for rotation, acceleration ad gravity and hearing? • What is a cupula and where are they located? • What are the “hairs” on a hair cell called and which one is more numerous? • No matter where they are located in the ear, all hair cells activate when what happens to them? • What bends a cupula? • Know which way a cupula bends when we rotate to the left, right, anterior, and posterior. • Which semicircular canal is for “yes”, “no’ and “head tilting”? • Where are the maculae relative to the sacculae? • What is are statoconia, what are they made out of and what do many statoconia and gelatinous material form? • What happens to otoliths when we are in an elevator going up and down? • Know which way otoliths swift when we tilt to the left, right, anterior, and posterior. • Which way do are otoliths shift If we are in a car at a red light and speed off quickly or driving fast and stop quickly? (anteriorly or posteriorly) • What does the cochlea look like, what are the three ducts inside of it, what part of it is stimulated by sound, where does sound enter, what ducts does it go through (in order) and where does it leave? • What structure vibrates (distorts) to activate the hair cells in the cochlea? • Where on the cochlea are low and high frequency sounds recognized? • In what lobe of the brain is the auditory cortex located?
Vision: • What are the accessory structures of the eye? • What do the accessory structures do? • Know which glandular infections result in a cyst or a sty. • What does lacrimal refer to? • Why do we get a runny nose when we cry? • What fills the posterior CAVITY and anterior CHAMBER of the eye? • What are the three tunics of the eye, what structures are located in them and what do those structures do? • Know the four layers of the retina and the order in which light passes through them. • What structure secretes the aqueous fluid (humor) and how does it get in to the blood stream? • What does the vitreous fluid (humor) support? • What are eye conditions that are related to the aqueous and vitreous fluid? • What are the steps in the visual pathway? (slide #44) • What area has 100% cones and what area has 0% rods and cones?