BIOS 1300 FINAL exam study guide questions and answers(latest update)

where does the spinal cord end in an adult L1-L2 what is inferior to the end of the spinal cord cauda equina how many spinal nerves for each section 8 cranial, 12 thoracic, 5 lumbar, 5 sacral, 1 coxxygeal why are the spinal nerves mixed nerves? because they contain both motor and sensory 4 parts of gray matter anterior horns, posterior horns, lateral horns, gray commisure what in the gray matter contains the motor nuclei? anterior horns what in the gray matter contains the sensory synapses? posterior horns what in the gray matter contains the autonomic nuclei? lateral horns what in the gray matter surrounds the central canal? gray commissure what is external to the gray matter white matter white mater is subdivided into 3 pairs of columns of funiculus individual tracts conduct either sensory signals from ________ or motor signal to ________ receptors: sensory effectors: motor most pathways _______ from one side of the body to another at some point as it travels decussate (cross over) referes to a relationship on the opposite side contralateral means the same side ispilateral has to travel up to the CNS afferent process sensory information from skin, muscle, joints somatosensory pathways process stimuli from the viscera viscerosensory pathways Afferent sensory pathways first order neuron, second order neuron, third order neuron which neuron does the dendrites of sensory neuron are part of receptor that defects stimulus cell body resides in DRG first order neuron which neuron does it use interneurons and projects to thalamus second order neuron which neuron does it use the interneuron begin in thalamus and ends in parietal lobe of cerebrum third order neuron carries motor information down the brainstem and spinal cord motor pathways- descending tracts function of Upper motor neuron excite or inhibitory activity of LMN cell body in cerebral cortex or brain stem Upper motor neuron cell body in anterior horn of spinal cord or nucleus of cranial nerve lower motor neuron where does LMN terminate skeletal muscle function of LMN always excitatory to skeletal muscle information that cortocospinal pathway carries voluntary motor organ composed of numerous nerve fibers (axons) bound by CT nerve most inside-surrounds neuron and fills space endoneurium surrounds each fascicle perineurium surrounds each nerve (large bundles of axons) epineurium ______ ______ nerves have a high metabolic rate blood vessel peripheral nerve fibers carry two types of info: motor (efferent) and sensory (afferent) collection of cell bodies outside the CNS ganglion what kind of axons originate from the spinal cord and exit via anterior (ventral) root motor axons what kind of axons have cell bodies in the DRG and enter the spinal coed via the posterior (dorsal) root sensory axons each anterior and posterior root unite in the ________ to form the _____________ intervertebral foramen to form the spinal nerve which ramus innervates deep back muscles (erector spine) and sensory for skin of back posterior (dorsal) which ramus innervates rest of trunk, limbs anterior (ventral) a specific segment of skin supplied by a single nerve dermatome network of interweaving anterior rami of spinal nerves nerve plexuses what are the 4 plexuses called cervical, brachial, lumbar, sacral which spinal nerves don't form plexuses? thoracic most important peripheral nerve phrenic nerve (C3-C5) which plexus supplies the upper limb and pectoral girdle and extends from the neck thro the axilla brachial plexus two important peripheral nerves that emerge from the lumbar plexus femoral nerve and obturator properties of a reflex rapid, pre-programmed, involuntary rxn of muscle or gland to a stimulus reflex arcs may be _____ or _____ (2 things) ipsilateral or contralateral, monosynaptic or polysynaptic sensory neurons synapse directly on motor neurons monosynaptic involves more synapses and interneurons polysynaptic example of monosynaptic stretch reflex example of polysynaptic withdraw reflex what is the subarachnoid space containing CSF what drains the csf in the arachnoid mater? arachnoid granulations the two layers of the dura meningeal and periosteal where the periosteal and meningeal are separated dural venous sinus