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68WM6 Nerv & Endo
nervous and endocrine systems
Question | Answer |
---|---|
delicate, web-like middle layer of meninges | Arachnoid Mater |
nerve tracts in the spinal cord that carry info to the brain | Ascending Tracts |
portion of the system that regulates the activities of the internal organs (viscera) | Autonomic Nervous System (visceral nervous system) |
slender, cylindrical nerve fiber; conducts a nerve impulse away from teh neuron cell body | Axon |
brain and spinal cord | Central Nervous System |
fluid in the ventricles of the brain, subarachnoid space of the meninges, and the central canal of the spinal cord | Cerebrospinal Fluid |
highly branched extensions of the cell body in a neuron that recieves input from other neurons | Dendrite |
nerve tracts in teh spinal cord that carry info from the brain to the muscles and glands | Descending Tracts |
tough outer layer of meninges that is surrounded by adiopose tissue and contains many blood vessels and nerves | Dura Mater |
motor neurons | Efferent Neurons |
a mass of neuron cell bodies, usually outside the CNS | Ganglia |
ridges or convultions on the surface of the Cerebrum separated by shallow grooves called a sulcus or deep groove called a fissure | Gyri |
membranes that cover the brain and spinal cord | Meninges |
efferent neurons carry impulse out of brain or spinal cord to muscles or glands | Motor Neuron |
fatty material that forms a sheath like covering around some axons and increases the speed of conduction through the neuron | Myelin |
nerve cell that can vary in size from 1 mm to 1 meter in length | Neuron |
chemical that an axon end secretes on an effector(muscle or gland) or another neuron | Neurotransmitter |
through sensation of changes in the internal and esternal environment, and responses to those changes, the nervous systerm coordinates all other body systems to maintain homeostasis | Nervous System Homeostasis |
narrow gaps in the Schwaan cells(myelin sheath) that allow the impulse is conducted from node to node(Saltatory conduction) and thus is sped up | Nodes of Ranvier |
portion of the autonomic nervous system that arises from the brain and sacral region of the spinal cord; most active under normal, restful conditions and counterbalances sympathetic nervous system | Parasympathetic Nervous System |
portion of the nervous system outside the central nervous system that has 31 pairs of nerves, efferent & afferent | Peripheral Nervous System |
inner layer of meninges that encloses the brain and spinal cord | Pia Mater |
cell surface structures that detect changes in teh environment and transmit a signal to the inside of the neuron | Receptors |
the difference in electrical charge between the inside and outside of an undisturbed nerve cell membrane | Resting Potential |
neuron the transmits an impulse from a receptor to the central nervous system | Sensory Neuron |
portion of the CNS extending from the brain stem through the vertebral cord | Spinal Cord |
space within the meninges between the arachnoid mater and the pia mater | Subarachnoid Space |
shallow groove on the surface of the brain | Sulcus |
portion of the autonomic nervous system that arises from the thoracic and lumbar regions of the spinal cord; prepares the body for energy-expending, stressful, or emergency situations | Sympathetic Nervous System |
connection between the axon of a neuron and the dendrite of another neuron | Synapse |
Connective tissue cells that supports neurons | Glia |
three major sections of a neuron | Axon, Dendrites, Cell Body |
difference between nerve cells and all other cells | no centrioles in nerve cells |
Types of Neurons | Sensory, Interneurons, Motor |
Afferent neuron | Sensory Neurons |
found only in the CNS where they connect neuron to neuron and are located only in the brain and spinal cord(CNS) | Interneurons |
nerve whose process is called continuous conduction and has an impulse that must travel the entire length of the axon at 0.5 meters/sec. white matter | Myelinated nerves |
nerves that contain Myelin Sheath and Nodes of Ranvier that the impulse travels faster due to saltatory conduction. 120 meters/sec | Unmyelinated nerves |
formed from the plasma membranes of specialized glial cells | Schwann cells |
Breaks or gaps between the Schwann cells and makes the nerve impulse "jumps" from gap to gap. | Nodes of Ranvier |
impulse that jumps from gap to gap | Saltatory conduction |
subdivision of the peripheral nervous system that consists of structures that regulate the body's automatic or involuntary functions | Autonomic Nervous system |
when sodium enters in a cell causing an action potential, the influx of positive Na+ ions makes the inside of the membrane more positive than the outside | Electrical current begins |
a brief period during which a membrane can not be stimulated | refractory period |
tiny space between neurons | Synaptic cleft |
the neurotransmitter that diffuses and the impulse leaps in the synaptic cleft. Most common in the PNS located in the vectiles of the axon. | Acetylcholine |
the receiving neuron | Postsynaptic neuron |
Two types of neurotransmitters in Synaptic conduction | Acetylcholine-parasympathetic, Norepinephrine-sympathic |
Two factors that influence the rate of conduction of the impulse | axon's diameter, presence(or absence) of a myelin sheath |
The simplest of nerve pathways that neurons do not pass directly into the brain but synapse in the spinal cord. Brain will still receive sensory input | Reflex Arc |
where most high-level brain functions take place. Contains 2 large hemispheres that make up 85% of the brain's weight | Cerebrum |
exterior surface of the cerebrum | Cerebral cortex |
the convoluted, folded gray layer of cell that covers an underlying mass of fibers and consists 75% of neuron cell bodies | grey matter |
mass of fiber located under grey matter | white matter |
4 lobes cerebrum is divided into | Frontal, Parietal, Temporal, Occipital |
Lobe in the brain that deals with numbers | Parital Lobe |
Lobe in the brain that deals with hearing | Temporal Lobe |
Lobe in the brain that deals with emotions | Frontal Lobe |
Lobe in the brain that deals with sight | Occipital Lobe |
Interconnected cavities within the cerebral hemispheres and brain stem that is filled with cerebrospinal fluid (CSF) | Ventricles |
two main components of the PNS | Sensory, motor |
afferent pathways that provid input from the body into the CNS | Sensory |
efferent pathways that carry signals to muscles and glands (effectors) | Motor |
two subdivisions of the PNS | Somatic, Autonomic |
nervous system that is voluntary. oversees conscious activity like you decide to stand, walk, or sit. consists of the cranial and spinal nerve fibers that connect to the CNS to the skin and skeletal muscles | Somatic Nervous System |
nervous system that is involuntary. oversees unconscious activity like muscles in internal organs | Autonomic Nervous System |
two subsystems of Autonomic Nervous System that are antagonism | Sympathetic, Parasympathetic |
Fight or Flight response in ANS. Emergency response | Sympathetic Nervous System |
Relaxation response in ANS. Provides homeostasis | Parasympathetic Nervous System |
complete or partial loss of sense of smell | Anosmia |
absence of an eye | Anopia |
thin, watery fluid that fills the space between the cornea and the iris (anterior chamber) | Aqueous Humor |
inflammation of the eyelid margins | Blepharitis |
middle, vascular layer of the eye | Choroid |
coiled tube in the inner ear where organ of hearing is located | Cochlea |
inflammation of the conjunctiva | Conjunctivitis |
the transparent front part of the eye that covers the iris, pupil, and anterior chamber | Cornea |
a nerve that arises from the underside of the brain or the brainstem | Cranial Nerve |
double vision | Diplopia |
blindness in one half of the visual field | Hemianopia |
colored muscular part of the eye | Iris |
complex system of connecting chambers and tubes of the inner ear | Labyrinth |
tear gland | Lacrimal Gland |
tough outer protective layer of the eye | Sclera |
senses that stem from receptors associated with specialized organs; nose, eye, ear, tongue | Special Senses |
eardrum | Tympanic Membrane |
clear jellylike substance within the eye | Vitreous Humor |
Cranial Nerve I-sensory nerve that carries the sense of smell and the receptors and supporting cells are located in the upper portion of the nasal cavity. Only nerve from the brain | Olfactory nerve |
Cranial Nerve II-sensory nerve that carries visual signals from the eye to the brain. Pathways terminate in the visual cortex of the occipital lobes | Optic nerve |
Cranial Nerve III-motor nerve taht moves the eye upward and side to side, raises the eyelid, and constricts pupils and focuses the lens | Oculomotor nerve |
Cranial Nerve IV-motor nerve that helps move the eye downward and away from the midline | Trochlear nerve |
Cranial Nerve V-mixed nerve that carries sensation from parts of the face and eye and motor impulses to the muscles of mastication | Trigminal nerve |