1. List the three major parts of the brain and describe their locations. A. cerebrum- constitutes about 83% of its volume and consists of a pair of half-globes called the cerebral hemispheres. B. cerebellum- lies inferior to the cerebrum and occupies the posterior cranial fossa. C. brainstem- that which remains of the brain if the cerebrum and cerebellum are removed. 2. Gyrus- a wrinkle or fold in the cortex of the cerebrum or cerebellum. Sulcus- a groove in the surface of an organ; as in the cerebrum, the heart, or a bone. 3. Name the parts of the brainstem from caudal to rostral. Medulla oblongata, pons, midbrain, diencephalon 4. Name the three meninges from superficial to deep. Dura mater, arachnoid mater, pia mater 5. Describe three functions of the cerebrospinal fluid. A. Buoyancy- allows the brain to attain considerable size without being impaired by its own weight. B. protection- protects the brain from striking the cranium when the head is jolted. C. chemical stability- rinses metabolic wastes from the nervous tissue and homeostatically regulates its chemical environment. 6. Where does the CSF originate, and what route does it take through and around the CNS? CSF originates in the choroid plexuses. Flow of CSF in the CNS: a. CSF is secreted by choroid plexus in each lateral ventricle. b. CSF flows through interventricular formina into third ventricle c. Choroid plexus in third ventricle adds more CSF.
d. CSF flows down cerebral aqueduct to fourth ventricle. e. Choroid plexus in fourth ventricle adds more CSF.
f. CSF flows out two lateral apertures and one median aperture. g. CSF fills subarachnoid space and bathes external surfaces of the brain and spinal cord. h. At arachnoid villi, CSF is reabsorbed into venous blood of dural venous sinuses. 7. Name the two components of the brain barrier system and explain the importance of this system. It regulates what substances get from the bloodstream into the tissue fluid of the brain. The two components are the blood-brain barrier (BBB) and the blood-CSF barrier. Page 437 #’s 8, 11, and 12
8. Name several functions controlled by nuclei of the medulla. Basic physiological functions: a cardiac center, which regulates the rate and force of the heartbeat; a vasomotor center, which regulates blood pressure and flow by dilating and constricting blood vessels; two respiratory centers, which regulate the rate and depth of breathing; and others involved in speech, coughing, sneezing, salivation, swallowing, gagging, vomiting, and sweating. 11. Describe the reticular formation and list several of its functions. It is a loosely organized web of gray matter that runs vertically through all levels of the brainstem and has connections with many areas of the cerebrum. I occupies much of the space between the white fiber tracts and the more anatomically distinct brainstem nuclei. Functions include: somatic motor control, equilibrium, visual attention, breathing, swallowing, cardiovascular control, pain modulation, sleep, and consciousness. 12. Describe the general functions or the cerebellum. Muscular coordination, fine motor control, muscle tone, posture, equilibrium, judging passage of time, some involvement in emotion, processing tactile input, spatial perception, and language. Page 449 #’s 13, 14, and 16
13. What is the role of the thalamus in sensory function? almost all sensory signals pass through the thalamus, which processes them and relays coded signals to the appropriate regions of the cerebral cortex; it is the “gateway to the cerebral cortex.” 14. List at least six functions of the hypothalamus. Hormone secretion, autonomic effects, thermoregulation, food and water intake, sleep and circadian rhythms, emotional responses, and memory 16. Where are the basal nuclei located? What is their general function? The basal nuclei are masses of cerebral gray matter buried deep in the white...