BIOL 243 1st EditionFinal Exam Study Guide Lectures: 1 - 12Lecture 1 (April 8)1. Ventricles-fluid filled cavities with cerebrospinal fluida. Lateral-embedded in cerebrum (one in each hemisphere)b. Third-thalamus forms wall. Hypothalamus is floor. Connected to fourth viacerebral aqueductc. Fourth-embedded in medulla oblongata2. Meninges-covering of brain and spinal cord3. Dura mater-most superficial, strong fibrous connective tissue; invade fissure4. Arachnoid layer-deep to dura mater; thin, delicate; adhere to dura mater5. Pia mater-adhere to surface of brain; very thina. Between arachnoid and pia mater is subarachnoid space which has cerebrospinal fluidLecture 2 (April 15)1. Choroid plexus-consists of capillaries; where cerebrospinal fluid is formed2. Dural sinuses-blood vessels3. Arachnoid villi-project into the dural sinuses4. Pathway of CSF: Choroid plexusventriclesmedial and lateral aperturesubarachnoid layerarachnoid villidural sinuses5. Spinal cord-continuation of the medulla oblongataa. Goes to first lumbar vertebraeb. Filum terminale-connective tissue; connects spinal cord to bones in coxal areac. Cauda equina-nerves at end of spinal cordd. Enlargements-cervical and lumbar-sacral6. Gray matter-H shapeda. Posterior-dorsal horns-sensory; association neurons and unmyelinatedb. Anterior-ventral horns-motor neuronsc. Lateral horns-autonomic motor neurons; thoracic and lumbar region onlyd. Dorsal root-strictly sensorye. Ventral root-motor neurons onlyf. Spinal nerve-where d and v merge7. White matter-myelinateda. Columns-anterior, posterior, lateralb. Tracts-ascending (sensory) and descending (motor)8. Sensory Pathwaysa. Fasciculus gracilis- fine touch, motor position, lower limbsi. 1st neuron in pathway-1st order-cell body in dorsal root ganglia to medulla synapseii. 2nd order-cross from one side of the brain to the other  thalamus  synapseiii. 3rd order- To cortexb. Lateral spinothalamic tract- temperature, coarse touchi. 1st- cell body in dorsal root ganglia  synapse in the spinal cordii. 2nd- cross  thalamus  synapseiii. 3rd- cerebral cortexc. Descending (motor)i. 2 or 3 neuron pathwayii. Crossiii. Pyramidal tract- controls fine movement, primary motor area of the brainiv. Extra pyramidal-balance, posture, etc9. Spinal reflexes-pathways that result in motor output but the brain is not involveda. Stretchb. Flexor or withdrawalc. Crossed extensorLecture 3 (April 17)1. Peripheral Nervous systema. Cranial nerves-12b. Spinal nerves-31c. Dorsal root-sensoryd. Ventral root-motore. Dermatome-patches of skin for spinal nerve. Sensory neurons at surface of skinf. Referred pain-projection of visceral pain inaccuratelyg. Nerve fiber-axon plus coveringi. Endometrium-coveringii. Fascicles-groups of fibersiii. Perineurium-surround fasciclesiv. Whole nerve-epineuriumv. All are mixed nerves except dorsal and ventral rooth. Nerve regeneration-PNSi. Nerve is cutii. Distal axon degeneratesiii. Schwann cells aligniv. Nerve regeneratesi. Nerve regeneration- CNS- virtually no regenerationj. Sensory receptorsi. Exteroceptors-skin-special sensesii. Interoceptors-1. Visceroceptors- internal2. Proprioceptors- skeletal muscles, tendons, joints, position of body partsk. Classification by stimulusi. Mechanoreceptors-touchii. Thermoreceptors- tempiii. Photoreceptors- lightiv. Chemoreceptors-changes in chemicalsv. Nociceptors-painl. Classification by structurei. Unencapsulated1. Free sensory nerve ending-respond to chemical, temp, etc2. Merkel’s disc-found in deep epidermis3. Root-hair plexus- wrap around hair folliclesii. Encapsulated1. Meisseners- hairless skin and dermal papillae2. Pacinian- dermis; deep pressure3. Ruffini- dermis; hypodermis2. Diseases of the Nervous Systema. Poliomyelitis-affects motor neurons, invades ventral horn; causes paralysis; severity depends on which cells are invadedb. Cerebral palsy-group pf motor disorders caused by damage to motor area of the brain at young age; caused by german measles; oxygen starvation during birthc. Multiple sclerosis (MS)- onset of 20-40 yrs old; progressive destruction of the myelin sheath of the myelin sheath in the CNSd. Alzhemiers-memory loss, short attention span, most common in elderly; abnormal protein deposits in braine. Cerebrovascular accidents- strokes- blood vessels that supply the brain are blocked or altered; can be mild or seriousLecture 4 (April 22)The eye structure and layers 1. Fibrous tunicSclera-white of eye 5/6Cornea- clear part that light passes through; Focus light usingRefraction- bending light as it goes from one substance to anotherAccommodation- referring to a change in the curvature of the lens for close vision (changing of the lens)2. Vascular Tunic: a lot of blood vesselsa. Choroid layer- dark part of eyeb. Ciliary body-i. smooth muscles: helps with looking long distance or close upii. ciliary processes: secrete aqueous humorc. Lens: suspensory ligament; Sometimes lens becomes cloudy(damaged); Cataracts- clouding of the lensd. Iris- muscular diaphragm. (Color part of eye); Has various muscles3. Retinaa. Pigmented-smaller layer; Rods and cones are imbedded here. With a series of membrane discsb. Nervous tissue layer-a. Photoreceptors- detect lighta. Two classes: rods and cones1. Rods- black and white, work best in peripheral (back), and in low light levels: night time2. Processes from light to dark in rods effected by Na+ ion channels; b. Found in rods: opsin and cis-retinal that are joined together to form rhodopsins. (Dark)(Light) retinal changes structure into all-trans retinal and un combine from opsin. Called bleachingAbundant cGMP present- the resting state4. Dark(occurring on photoreceptors)cGMP gates channels will openCalcium flow into cellsRelease of a neurotransmitterBipolar cellsGenerates an inhibitory post synaptic potential (IPSP)Hyper polarizeNo neurotransmitter releasedGanglia cells are bit stimulated.5.LightOpposite of dark process.Bipolar cells are not inhibited with action potential.Cones- colors(red,green,blue). Work best in high light levels: bright day. Localized at very back of the eye.Fovea centralis: back of eye with high level of cones, macula lutea is the middleOuter sectors contain various disk in pigmented area of photoreceptors. Connected to bipolar cells which is then connected to ganglia cells.Opsins- proteins that recognize different wavelength of light. Three on cones and one in rods all different.Retinal- absorb light, change structure when