CSN A&P 223 exam 4 study guide Questions With Complete Solutions, Exams of Nursing

Download CSN A&P 223 exam 4 study guide Questions With Complete Solutions and more Exams Nursing in PDF only on Docsity! CSN A&P 223 exam 4 study guide Questions With Complete Solutions What are an ascending and a descending pathway? Ascending pathway: A nerve pathway that goes upward from the spinal cord toward the brain carrying sensory information from the body to the brain. In contrast, descending pathways are nerve pathways that go down the spinal cord and allow the brain to control movement of the body below the head What is white matter.... gray matter? White matter consist of myelinated axons, which for nerve tracts - found deep to basal cortex; around basal nuclei Gray matter consist of neuron cell bodies, dendrites, and axons - found in cerebral cortex and basal nuclei Describe the three layers of the meninges and their functions. 1) Dura Mater Inner fibrous layer= meningeal layer (lines the endosteal layer) Outer fibrous layer= endosteal layer (thickest layer) -Function: surrounds and supports the Dural sinuses and carries blood from the brain toward the heart. Protects brain from cranial trauma. - location: tough, fibrous membrane forming the outer covering of the brain and spinal cord 2) Arachnoid Mater -Function: covers brain, contacts epithelial layer of Dura mater. The subarachnoid space is between arachnoid and the pia mater and is normally filled with cerebrospinal fluid -Location: thin, cobweb-appearing meningeal layer surrounding the brain, the middle of the 3 layers 3)Pia Mater -Function: protects the brain from cranial trauma -location: attached to the brain surface by astrocytes Where would a subdural hematoma occur? Subdural hematomas are much more common, occurring in 10- 20% of major head injuries. They most commonly involve tears in the cortical veins or Dural venous sinuses in the superior portion of the cranial cavity What is found in the subarachnoid space? cerebrospinal fluid What is the function of the arachnoid granulations? CSF passes into the blood-filled Dural venous sinuses through the these granulations (large clusters of villi that; Absorb CSF into venous circulation) cranial bones, so the epidural space of the cranial cavity is only a potential space What are the dorsal and ventral roots? The ventral roots (anterior roots) allow motor neurons to exit the spinal cord. The dorsal roots (posterior roots) allow sensory neurons to enter the spinal cord. Along each dorsal root is small bulge called the dorsal root ganglion (or spinal ganglion). Inside the ganglia are the cell bodies of the sensory neurons Describe a reflex arc. The basic functional unit of the nervous system is the reflex arc because it is the smallest, simplest portion capable of receiving a stimulus and producing a response -A reflex is an automatic response to a stimulus produced by a reflex arc. That means it occurs without conscious thought Why is the reflex arc a protective mechanism? Provides a fast response, protection from greater injury What are the major divisions of the brain? Cerebrum, Cerebellum, Diencephalon, and Brainstem Describe the structure of the cerebrum? Controls conscious perception, thought, and conscious motor activity; can override most other systems What are gyri...sulci? -The most conspicuous features on the surface of each hemisphere are numerous folds called gyri; which greatly increase the surface area of the cortex. -The grooves between the gyri, called sulci, divide each hemisphere into lobes. Be able to locate the different functional areas of the cerebrum discussed in class. Basal nuclei Controls muscle activity and posture; largely inhibits unintentional movement when at rest Limbic system Autonomic response to smell, emotion, mood, memory, and other such functions What is the cerebral cortex? The gray matter on the outer surface of the cerebrum is the cerebral cortex, and clusters of gray matter deep inside the brain are nuclei. The cerebral cortex contains a number of neuron types, named largely for their shape, such as fusiform cells, stellate cells, and pyramidal cells What are the parts of the diencephalons? Thalamus, epithalamus (pineal gland), and hypothalamus What are the components of the limbic system and what is the limbic system's function. The Limbic System function: processing of memories; creation of emotional states, drives, and associated behaviors. Components of the Limbic System: Amygdaloid body - acts as a interface between the limbic system, the cerebrum and various sensory systems -Limbic lobe of cerebral hemisphere -Cingulate gyrus -Dentate gyrus -Parahippocampal gyrus -Hippocampus - Fornix - Tract of white matter -connects hippocampus and hypothalamus - Anterior nucleus of the thalamus - relays information from the mammillary body to the cingulate gyrus - Reticular formation -Stimulation or inhibition affects emotions (rage, fear, pain, sexual arousal, pleasure) We have an expert-written solution to this problem! What is the function of the tectum and the tegmentum? (midbrain) The basal ganglia,(also known as basal nuclei), is a region on the underside of the brain that plays a very important role in muscle coordination and movement. Ganglia refers to a cluster of neurons, (or brain cells), outside of the brain or spinal cord, while the term nuclei refers to clusters within those regions -It's responsible for executing a skill pattern; plays a large role in eye movements, allowing someone to direct their gaze to a target and then change their gaze from one target to another. ex Parkinson's disease, which can result from a malfunctioning basal ganglia What are the three parts of the brain stem? the medulla oblongata, pons, and midbrain What is an ascending and descending nerve tract? Ascending tracts -Sensory-Deliver information to the brain Descending tracts -Motor-Deliver information to the periphery Name the primary functions of the hypothalamus. 1) Provides subconscious control of skeletal muscle 2) Controls autonomic function 3) Coordinates activities of nervous and endocrine systems 4) Secretes hormones - Antidiuretic hormone (ADH) by supraoptic nucleus - Oxytocin (OT; OXT) by paraventricular nucleus 5) Produces emotions and behavioral drives - the feeding center (hunger) - the thirst center (thirst) 6) Coordinates voluntary and autonomic functions 7) Regulates body temperature 8) Controls circadian rhythms (day-night cycles) Name the 5 cranial nerves associated with the medulla oblongata. VIII- Vestibulocochlear-senses of hearing (cochlear nerve) and balance IX- Glossopharyngeal-sense of taste from posterior one-third of tongue; sensory from pharynx, palatine tonsils, posterior one- third of tongue, middle ear, carotid sinus, and carotid body X- Vagus- sensory from inferior pharynx, larynx, thoracic and abdominal organs; sense of taste from posterior tongue XI- Accessory-motor to sternocleidomastoid and trapezius XII- Hypoglossal- motor to intrinsic and extrinsic tongue muscles (styloglossus, hypoglossus, genioglossus) and throat muscles (thyrohyoid and geniohyoid) Proprioceptive from those muscles What is the function of the pons? Contains ascending and descending nerve tracts; relays information between cerebrum and cerebellum; site of reflex centers What is the importance of the gyri on the surface of the cerebrum? It greatly increases the surface area of the cortex and the number of gyri determine intelligence What is the function of the medulla oblongata? Pathway for ascending and descending nerve tracts; center for several important reflexes (e.g., heart rate, breathing, swallowing, vomiting) Is the brain stem involved in higher thought processes? NO, the cerebral cortex is involved with higher thought processes Describe the characteristics of the blood brain barrier and the blood cerebral spinal fluid barrier. Blood-CSF Barrier - formed by special ependymal cells -surrounds capillaries of choroid plexus -limits movement of compound transferred -allows chemical composition of blood and CSF to differ Blood-Brian Barrier -isolates CNS neural tissue from general circulation -formed by network of tight junctions -between endothelial cells of CNS capillaries -lipid-soluble compounds (O'2, CO2), steroids, and 1) Flax Cerebri- Projects between the cerebral hemisphere 2)* Tentorium Cerebelli - Separates cerebellum and cerebrum 3) Flax Cerebelli- divides cerebellar hemisphere below the tentorium cerebelli What is the choroid plexus? Where is it found? What is its function? The choroid plexus is a secretory structure that produces CSF and is located within cerebral ventricles How are the brain and the endocrine similar? The endocrine system influences almost every cell, organ and function of the body. It plays a central role in mood regulation, growth and development, tissue function, metabolism, sexual function and reproductive processes. The autonomic nervous system functions without the body's awareness or control. The hypothalamus(which is apart of the brain) receives information and is involved in a number of functions of the nervous system. The hypothalamus is the part of the brain that maintains homeostasis within the body. To achieve this, the hypothalamus must receive inputs about the state of the body, and must be able to initiate changes if an imbalance occurs What could lesions in the limbic system cause? The limbic system plays a central role in basic survival functions, such as memory, reproduction, and nutrition. It is also involved in interpreting sensory input and emotions in general. Damage to parts of the limbic system severely affects ability to store and retrieve information in the conscious memory What are arachnoid villi and arachnoid granulations. What are their functions? -Arachnoid Villi are extensions of the subarachnoid space that extend through the Dura mater to the superior sagittal sinus. (they are collection areas for excess CSF) -Arachnoid granulations are clusters of villi, fingerlike protusions of arachnoid tissue, that penetrate into the Dural venous sinuses, especially the superior sagittal sinus. CSF passes into the blood-filled Dural venous sinuses through these granulations. (absorb CSF into venous circulation) What are the generalized functions of the cranial nerves? I Olfactory- (sensory) smell II Optic- (sensory) Vision II Oculomotor- (motor) Raise eyelids, moves the eye, and controls iris IV Trochlear- (motor) Moves the eye V Trigeminal- (Both) (motor) Muscles for chewing, (sensory) sensations from the eyes, tears, glands, scalp, forehead, gums, teeth VI Abducens- (motor) moves the eye VII Facial- (Both) (motor) Muscles of facial expression, touch, pain and temp from face, tear glands and salivary glands, (sensory) taste VIII Vestibulocochlear- (sensory) hearing and balance (equilibrium) IV Glossopharyngeal- (both) (motor) Muscles of pharynx and salivary glands, swallowing, gag reflex, (sensory) bitter taste, sensations from tonsils, and pharynx X Vagus- (*both) (motor)Autonomic motor control of viscera of thorax and abdomen, decreases heart rate, constriction of respiratory passages, (sensory) sensations from pharynx, larynx, esophagus and viscera XI Accessory- (motor) Muscles of pharynx and larynx, soft plate. Muscle of neck and back XII Hypoglossal - (motor) Muscles of the tongue Name the major nuclei found in the medullar oblongata and describe their function? Medulla Oblongata contains sensory and motor tracts, cranial nerve nuclei, and related nuclei. Gray matter in 3 Groups of Nuclei 1)Sensory and Motor Nuclei associated with 5 cranial nerves VIII Vestibulocochlear- hearing IV Glossopharyngeal- bitter taste, swallowing, and saliva production -Frontal lobe is important in voluntary motor function, motivation, aggression, the sense of smell, and mood -Temporal lobe receives and evaluates input for smell and hearing and plays an important role in memory -Parietal lobe is the major center for receiving and evaluating most sensory information, except for smell, hearing, taste, and vision. -Occipital lobe functions in receiving and integrating visual input and is not distinctly separate from the other lobes -Insula receives and evaluates taste information and is often referred to as a fifth lobe. Where does alcohol affect the brain? Alcohol affects the cerebellum. Alcohol crosses the Blood- Brain-Barrier What are the two divisions of the autonomic nervous system? Sympathetic division ("fight or flight")-prepares our body for action Parasympathetic division ("Rest and Digest")-helps produce a state of equilibrium in the body Where is the arbor vitae located and what is it's function? -highly branched, internal white matter of cerebellum - Cerebellar nuclei embedded in Arbor Vitae - They relay information to Purkinjie cells What is the function of the midbrain? Contains ascending and descending nerve tracts; serves as visual reflex center; part of auditory pathway