Nervous System Functions and Impulses
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Questions and Answers

What are the three main functions of the nervous system?

  • Central, Peripheral, Autonomic
  • Somatic, Autonomic, Enteric
  • Sensory, Integrative, Motor (correct)
  • Brain, Spinal Cord, Nerves

    • The central nervous system (CNS) is comprised of the brain and the peripheral nerves.

    False (B)

    What type of cell is responsible for generating nerve impulses?

    neurons

    The ______ nervous system is responsible for controlling voluntary movements.

    <p>somatic</p> Signup and view all the answers

    Match the following nervous system components with their corresponding functions:

    <p>Brain = Integrates sensory information and initiates motor commands Spinal Cord = Relays information between the brain and the rest of the body Peripheral nerves = Carry signals to and from the CNS Sensory receptors = Detect changes in the environment</p> Signup and view all the answers

    Action Potentials (AP) are used for communication over both short and long distances.

    <p>True (A)</p> Signup and view all the answers

    What type of ion channels respond to direct changes in membrane potential?

    <p>Voltage-gated channels (C)</p> Signup and view all the answers

    The type of ion channels that randomly open and close are called ______ channels.

    <p>leak</p> Signup and view all the answers

    What are the two types of electrical signals used for communication in excitable cells?

    <p>Action Potentials (AP) and Graded Potentials (GP)</p> Signup and view all the answers

    Match the type of ion channel with its corresponding stimulus:

    <p>Leak channels = Random opening and closing Ligand-gated channels = Chemical Mechanically-gated channels = Mechanical vibration or pressure Voltage-gated channels = Changes in membrane potential</p> Signup and view all the answers

    Which of the following characteristics is unique to action potentials, but not present in graded potentials?

    <p>Refractory period (B)</p> Signup and view all the answers

    Action potentials can die out as they travel along the axon.

    <p>False (B)</p> Signup and view all the answers

    What is the name of the process by which action potentials travel from the trigger zone to the axon terminals?

    <p>Propagation</p> Signup and view all the answers

    The speed of action potential propagation is influenced by factors such as axon ______ and the presence of ______.

    <p>diameter, myelin</p> Signup and view all the answers

    Match the following features of action potentials and graded potentials with their corresponding descriptions.

    <p>Amplitude = Varies depending on stimulus strength Duration = Relatively short, lasting from 0.5 to 2 milliseconds Refractory period = Present, prevents immediate generation of a new impulse Summation = Can occur in graded potentials, not in action potentials</p> Signup and view all the answers

    What are the two types of summation that can occur in nerve impulses?

    <p>Spatial and Temporal (B)</p> Signup and view all the answers

    Enkephalins are known to enhance the perception of pain.

    <p>False (B)</p> Signup and view all the answers

    What is the primary role of nitric oxide as a neurotransmitter?

    <p>Nitric oxide is involved in a variety of processes, including learning, memory, and blood vessel dilation.</p> Signup and view all the answers

    Dynorphins are thought to play a role in ______ and registering emotions.

    <p>controlling pain</p> Signup and view all the answers

    Match the following neuropeptides with their primary functions:

    <p>Substance P = Enhances perception of pain Enkephalins = Inhibits pain and may play a role in memory and learning Endorphins = Inhibits pain and may have roles in memory, learning, and sexual activity Dynorphins = May be involved in controlling pain and registering emotions</p> Signup and view all the answers

    The ______ enlargement of the spinal cord handles motor output and sensory input to and from the legs.

    <p>lumbar</p> Signup and view all the answers

    In the brain, gray matter is found on the outside, while white matter resides on the inside.

    <p>True (A)</p> Signup and view all the answers

    What is the primary function of the posterior (dorsal) root and rootlets of the spinal cord?

    <p>Carry sensory signals from the body to the central nervous system (D)</p> Signup and view all the answers

    What is the name of the swelling on the posterior root that contains the cell bodies of sensory neurons?

    <p>Posterior (dorsal) root ganglion</p> Signup and view all the answers

    Match the following structures with their corresponding locations:

    <p>Dura mater = Outermost layer of the meninges Epidural space = Space between the dura mater and the vertebral canal Ligamentum flavum = Connective tissue that connects adjacent vertebrae Subarachnoid space = Space between the arachnoid mater and the pia mater Pia mater = Innermost layer of the meninges</p> Signup and view all the answers

    A lumbar puncture is a procedure where a needle is inserted into the subarachnoid space to withdraw cerebrospinal fluid (CSF).

    <p>True (A)</p> Signup and view all the answers

    Which of the following is NOT a common reason for performing a lumbar puncture?

    <p>To remove a blood clot from the brain (D)</p> Signup and view all the answers

    The site used for most lumbar punctures is between the ___ and ___ lumbar vertebrae.

    <p>3rd and 4th</p> Signup and view all the answers

    What is the primary function of spinal nerves?

    <p>To connect the central nervous system (CNS) to sensory receptors, muscles, and glands.</p> Signup and view all the answers

    Match the following connective tissue coverings with their corresponding location:

    <p>Epineurium = Surrounds the entire nerve Perineurium = Surrounds fascicles within a nerve Endoneurium = Surrounds individual nerve fibers within a fascicle</p> Signup and view all the answers

    Which of the following nerve plexuses is responsible for supplying the skin and muscles of the head, neck, superior portion of the shoulders and chest, and diaphragm?

    <p>Cervical plexus (C)</p> Signup and view all the answers

    The posterior rami of the segmental nerves join together to form major nerve plexuses.

    <p>False (B)</p> Signup and view all the answers

    What is the name of the nerve that provides motor innervation to the diaphragm?

    <p>Phrenic nerve</p> Signup and view all the answers

    The ______ nerve is the most important nerve of the brachial plexus, resulting in carpal tunnel syndrome when lesioned.

    <p>median</p> Signup and view all the answers

    Match the following nerve plexuses with their primary areas of innervation.

    <p>Cervical plexus = Head, neck, superior portion of shoulders and chest, diaphragm Brachial plexus = Shoulders and upper limbs Lumbar plexus = Anterior and medial thigh, leg, and foot Sacral plexus = Posterior thigh, leg, and foot</p> Signup and view all the answers

    Which of the following injuries could result in a "winged scapula"?

    <p>Injury to the long thoracic nerve (B)</p> Signup and view all the answers

    Erb's palsy is a type of brachial plexus injury that typically occurs in infants during childbirth.

    <p>True (A)</p> Signup and view all the answers

    What is the name of the condition that occurs when the ulnar nerve is compressed at the medial epicondyle of the humerus?

    <p>Funny bone</p> Signup and view all the answers

    Carpal tunnel syndrome is a common type of ______ nerve injury.

    <p>median</p> Signup and view all the answers

    Match the following nerves with their primary functions:

    <p>Long thoracic nerve = Supplies the serratus anterior muscle Ulnar nerve = Supplies the medial half of the hand Median nerve = Supplies the palm and fingers Brachial plexus = A network of nerves that innervate the upper limb</p> Signup and view all the answers

    Which of the following structures is NOT part of the diencephalon?

    <p>Cerebellum (A)</p> Signup and view all the answers

    The thalamus is the relay station for all sensory impulses, including smell, to the cerebral cortex.

    <p>False (B)</p> Signup and view all the answers

    What is the primary function of the hypothalamus?

    <p>The hypothalamus controls many body activities, including regulating homeostasis, secreting hormones, and controlling the pituitary gland.</p> Signup and view all the answers

    The ______ gland secretes melatonin, which is involved in regulating sleep-wake cycles.

    <p>pineal</p> Signup and view all the answers

    Match the following structures with their primary functions:

    <p>Thalamus = Relays sensory information to the cerebral cortex Hypothalamus = Regulates body temperature, hunger, thirst, and sleep-wake cycles Epithalamus = Contains the pineal gland and is involved in olfaction Cerebellum = Coordinates muscle movements and maintains balance</p> Signup and view all the answers

    Which of the following brain wave types is associated with periods of sensory input and mental activity?

    <p>Beta waves (C)</p> Signup and view all the answers

    Alpha brain waves are present during sleep.

    <p>False (B)</p> Signup and view all the answers

    What is the name of the recording that measures brain wave activity?

    <p>Electroencephalogram (EEG)</p> Signup and view all the answers

    The ______ waves occur during deep sleep in adults and in awake infants.

    <p>Delta</p> Signup and view all the answers

    Match the following types of brain waves with their corresponding states:

    <p>Alpha waves = Awake and resting with eyes closed Beta waves = Active nervous system, sensory input and mental activity Theta waves = Emotional stress Delta waves = Deep sleep in adults and awake infants</p> Signup and view all the answers

    What structure in the brain plays a key role in the maintenance of consciousness?

    <p>Thalamus</p> Signup and view all the answers

    Which of the following is NOT produced by the hypothalamus?

    <p>Insulin (B)</p> Signup and view all the answers

    The corpus callosum connects the right and left hemispheres of the cerebrum.

    <p>True (A)</p> Signup and view all the answers

    The ______ lobe of the cerebrum is responsible for processing visual information.

    <p>Occipital</p> Signup and view all the answers

    Match the following brain structures with their primary functions:

    <p>Cerebellum = Coordination of movement and balance Basal nuclei = Initiating and regulating movements Limbic system = Emotional responses and memory Brainstem = Regulation of basic life functions, such as breathing and heart rate</p> Signup and view all the answers

    Which of the following structures protects the brain?

    <p>All of the above (D)</p> Signup and view all the answers

    The dura mater is composed of a single layer in the brain and spinal cord.

    <p>False (B)</p> Signup and view all the answers

    What is the name of the structure that connects the two hemispheres of the brain?

    <p>Corpus callosum</p> Signup and view all the answers

    The _____ arteries and _____ arteries supply blood to the brain.

    <p>vertebral, carotid</p> Signup and view all the answers

    Match the following brain coverings with their descriptions:

    <p>Dura mater = The outermost layer of the meninges, tough and fibrous. Arachnoid mater = The middle layer of the meninges, thin and web-like. Pia mater = The innermost layer of the meninges, delicate and closely adheres to the brain.</p> Signup and view all the answers

    Which of the following is NOT a characteristic of the somatic nervous system?

    <p>Uses a two-neuron pathway (B)</p> Signup and view all the answers

    The autonomic nervous system is primarily responsible for controlling involuntary bodily functions.

    <p>True (A)</p> Signup and view all the answers

    The ______ nervous system is responsible for the 'fight-or-flight' response.

    <p>sympathetic</p> Signup and view all the answers

    What are the two primary neurotransmitters used by the autonomic nervous system?

    <p>Acetylcholine and norepinephrine</p> Signup and view all the answers

    Match the following autonomic nervous system divisions with their primary functions:

    <p>Parasympathetic = Fight or flight Sympathetic = Rest and digest</p> Signup and view all the answers

    Where are the cell bodies of sympathetic preganglionic neurons located?

    <p>Lateral horns of the gray matter in the 12 thoracic and first 2 or 3 lumbar segments (D)</p> Signup and view all the answers

    The parasympathetic division has a faster response system than the sympathetic division.

    <p>False (B)</p> Signup and view all the answers

    What are the two major types of sympathetic ganglia?

    <p>Sympathetic trunk ganglia and prevertebral ganglia</p> Signup and view all the answers

    The ______ nerve carries approximately 80% of the parasympathetic flow.

    <p>vagus</p> Signup and view all the answers

    Match the following terms with the correct description:

    1. Preganglionic neuron
    2. Postganglionic neuron
    3. Sympathetic trunk ganglia
    4. Prevertebral ganglia

    A. Lie in a vertical row on either side of the vertebral column B. Cell body located in an autonomic ganglion C. Cell body located in the brain or spinal cord D. Lie anterior to the vertebral column

    <p>1 = C 2 = B 3 = A 4 = D</p> Signup and view all the answers

    What is the primary neurotransmitter released by most sympathetic postganglionic neurons?

    <p>Norepinephrine (B)</p> Signup and view all the answers

    The autonomic nervous system always operates under conscious control.

    <p>False (B)</p> Signup and view all the answers

    What are the two main branches of the autonomic nervous system?

    <p>The two main branches of the autonomic nervous system are the sympathetic and parasympathetic nervous systems.</p> Signup and view all the answers

    The _________ nervous system controls skeletal muscle contractions.

    <p>somatic</p> Signup and view all the answers

    Match the following neurotransmitters with their corresponding locations in the autonomic nervous system:

    <p>Acetylcholine = All preganglionic neurons and parasympathetic postganglionic neurons Norepinephrine = Most sympathetic postganglionic neurons Epinephrine = Chromaffin cells of the adrenal medullae</p> Signup and view all the answers

    Which of the following is NOT a characteristic of the parasympathetic nervous system?

    <p>Stimulates increased alertness (D)</p> Signup and view all the answers

    Most autonomic motor pathways consist of two motor neurons in series.

    <p>True (A)</p> Signup and view all the answers

    What are the two main divisions of the autonomic nervous system?

    <p>Sympathetic and Parasympathetic</p> Signup and view all the answers

    The ______ nervous system is often referred to as the fight-or-flight division.

    <p>Sympathetic</p> Signup and view all the answers

    Match the following terms with their corresponding descriptions:

    <p>Interoceptors = Sensory receptors that monitor internal conditions Sympathetic Nervous System = Fight-or-flight division Parasympathetic Nervous System = Rest-and-digest division Autonomic Ganglion = A cluster of nerve cell bodies outside the central nervous system</p> Signup and view all the answers

    Flashcards

    Nervous System Functions

    The nervous system has three main functions: sensory, integrative, and motor.

    Neurons

    Neurons are electrically excitable cells that transmit nerve impulses called action potentials.

    Action Potential

    An action potential is a brief electrical charge in a neuron that propagates along its membrane.

    Neuroglia

    Neuroglia are support cells in the nervous system that protect and assist neurons.

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    Homeostasis

    Homeostasis is the maintenance of stable internal conditions in the body, supported by the nervous system.

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    Graded Potentials

    Changes in membrane potential that vary in strength, lasting longer than action potentials.

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    Propagation of Action Potentials

    The process by which action potentials travel along the neuron from the trigger zone to axon terminals without losing strength.

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    Factors Affecting Propagation Speed

    Propagation speed can be influenced by axon diameter, myelination, and temperature; larger and myelinated axons and higher temperatures increase speed.

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    Continuous vs. Saltatory Conduction

    Continuous conduction is unmyelinated and slower; saltatory conduction jumps between nodes on myelinated axons, increasing speed.

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    Summation

    The process where multiple signals combine to generate a nerve impulse.

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    Spatial Summation

    Occurs when multiple presynaptic neurons fire simultaneously to create an action potential.

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    Temporal Summation

    Occurs when a single presynaptic neuron fires rapidly to increase the likelihood of an action potential.

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    Neurotransmitters

    Chemicals that transmit signals across synapses in the nervous system.

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    Neuropeptides

    A type of neurotransmitter that modulates pain and emotional responses.

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    Action Potentials (AP)

    Electrical signals that allow communication over long and short distances in neurons.

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    Graded Potentials (GP)

    Electrical signals in neurons that communicate only over short distances.

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    Resting Membrane Potential

    The membrane potential of a neuron at rest, crucial for generating signals.

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    Ion Channels

    Protein channels in the membrane that control ion flow, essential for neural signaling.

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    Ligand-gated Channels

    Ion channels that open in response to the binding of a chemical (ligand).

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    Lumbar Puncture

    A procedure to collect cerebrospinal fluid (CSF) for diagnosis or treatment.

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    Cerebrospinal Fluid (CSF)

    A clear fluid surrounding the brain and spinal cord, crucial for protecting and nourishing them.

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    Cauda Equina

    A bundle of spinal nerves and nerve roots located below the end of the spinal cord.

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    Spinal Nerves

    31 pairs of nerves that connect the central nervous system (CNS) to the body’s sensory receptors, muscles, and glands.

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    Perineurium

    A protective sheath surrounding a fascicle of nerve fibers within a spinal nerve.

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    Lumbar Enlargement

    The region of the spinal cord that manages motor output and sensory input to the legs.

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    White Matter vs. Gray Matter

    In the spinal cord, white matter is outer and gray matter inner; the opposite is true in the brain.

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    Sensory and Motor Processing

    The internal structure of the spinal cord organizes sensory and motor information efficiently.

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    Posterior Root Ganglion

    A swelling on the posterior root containing sensory neuron cell bodies.

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    Epidural Anesthesia

    A pain relief method during labor, injecting anesthetic into the epidural space of the spine.

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    Long Thoracic Nerve

    A nerve from the brachial plexus that supplies the serratus anterior muscle; prone to injury.

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    Erb’s Palsy

    A paralysis of the arm due to excessive pulling during birth, affecting brachial plexus nerves.

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    Ulnar Nerve

    The largest unprotected nerve, responsible for sensations in the medial hand; injury causes symptom changes.

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    Median Nerve Injury

    Injury causing numbness and pain in the palm and fingers, often related to repetitive motion.

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    Serratus Anterior Muscle

    Muscle supplied by the long thoracic nerve; essential for arm movement and stability.

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    Nerve Plexus

    A nerve plexus is a network of nerves formed by the anterior rami of spinal nerves, providing a nerve supply to specific body regions.

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    Anterior Ramus

    The anterior ramus is the larger branch of a spinal nerve that supplies the limbs and trunk; it can form plexuses or travel alone like intercostal nerves.

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    Cervical Plexus

    The cervical plexus supplies sensation and motor function to the head, neck, shoulders, chest, and diaphragm, primarily through the phrenic nerve.

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    Phrenic Nerve

    The phrenic nerve originates from the cervical plexus (C3-C5) and controls the diaphragm, crucial for breathing.

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    Neural Tube

    The thickening of ectoderm that develops into the nervous system.

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    Cranial Meninges

    Three membranes protecting the brain: pia mater, arachnoid, dura mater.

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    Circle of Willis

    A circle of arteries supplying blood to the brain.

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    Cerebrospinal Fluid

    Fluid surrounding the brain and spinal cord, providing protection and nourishment.

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    Falx Cerebri

    A fold of dura mater attaching to the crista galli that separates the brain's hemispheres.

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    Cerebellum

    Coordinates skeletal muscle contractions and maintains muscle tone, posture, and balance.

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    Diencephalon

    Part of the brain composed of thalamus, hypothalamus, and epithalamus.

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    Thalamus

    Relay station for all sensory impulses except smell, directing them to the cerebral cortex.

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    Hypothalamus

    Regulates body activities and homeostasis; connects nervous and endocrine systems via hormones.

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    Epithalamus

    Includes the pineal gland, which secretes melatonin, important for sleep regulation.

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    Brain Waves

    Detectable electrical signals generated by brain neurons, primarily from the cerebral cortex.

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    Electroencephalogram (EEG)

    A record of brain waves, created by placing electrodes on the scalp.

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    Alpha Waves

    Brain waves present during wakefulness and relaxation, disappearing during sleep.

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    Theta Waves

    Brain waves associated with emotional stress in children and adults.

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    Delta Waves

    Slow brain waves occurring during deep sleep in adults and in awake infants.

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    Cerebral Cortex

    The outer layer of the brain made of gray matter, with gyri and sulci.

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    White Matter

    Deep brain tissue composed of neuron tracts connecting different brain areas.

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    Basal Nuclei

    Masses of gray matter that initiate and suppress movements.

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    Limbic System

    Brain structure associated with emotions and behaviors, regulating memory and pleasure.

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    Autonomic Nervous System (ANS)

    A part of the nervous system that controls involuntary functions, such as heart rate and digestion.

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    Somatic Nervous System

    The division of the nervous system associated with voluntary control of body movements via skeletal muscles.

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    Sensory Input in ANS

    Sensory information received by the autonomic nervous system primarily from interneceptors related to organs.

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    Sympathetic vs. Parasympathetic

    Sympathetic prepares the body for fight or flight; parasympathetic promotes rest and digest activities.

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    Neurotransmitters in ANS

    Chemicals that transmit signals across synapses in the autonomic nervous system, affecting body functions.

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    Motor Neuron Pathways

    Pathways that carry signals from the CNS to effector organs; includes one-neuron and two-neuron types.

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    Preganglionic Neurons

    Neurons that extend from the CNS to synapse with postganglionic neurons in the autonomic ganglion.

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    Autonomic Nervous System Effectors

    Organs that respond to autonomic signals; include smooth and cardiac muscle as well as glands.

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    Interoceptors

    Sensory receptors in blood vessels and organs responsible for monitoring internal environment conditions.

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    Motor Neurons in ANS

    Each autonomic division has preganglionic and postganglionic neurons for signaling.

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    Sympathetic Division Location

    Preganglionic neurons are located in the lateral horns of the thoracic and lumbar spinal segments.

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    Parasympathetic Division Characteristics

    Mainly uses cranial nerves and sacral spinal segments; 80% of flow via vagus nerve.

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    Types of Autonomic Ganglia

    Includes sympathetic and parasympathetic ganglia; sympathetic has trunk and prevertebral ganglia.

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    Sympathetic Neural Pathway

    Preganglionic neurons synapse in sympathetic trunk ganglia with postganglionic neurons in multiple ways.

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    Sympathetic Nervous System

    Part of the ANS that prepares the body for 'fight or flight' responses during emergencies.

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    Parasympathetic Nervous System

    Part of the ANS that promotes 'rest and digest' activities, slowing down bodily functions.

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    Autonomic Motor Pathways

    Consist of two neurons; preganglionic from the CNS to a ganglion, and postganglionic from the ganglion to the effector.

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    Study Notes

    Nervous Tissue Overview

    • The nervous system maintains homeostasis by controlling conditions within limits.
    • It is composed of various branches and cell types.
    • Nervous tissue includes neurons and neuroglia.

    Nervous System Overview

    • Sensory neurons receive signals from receptors and transmit them to the central nervous system (CNS).
    • Interneurons connect other neurons within the CNS.
    • Motor neurons transmit signals from the CNS to effectors (muscles or glands).

    Nervous System Organization

    • Central Nervous System (CNS): Includes the brain and spinal cord.
    • Peripheral Nervous System (PNS): Includes cranial nerves, spinal nerves, enteric plexuses, and sensory receptors.
    • The PNS has a sensory division and a motor division.
      • The motor division includes the somatic nervous system (skeletal muscles) and the autonomic nervous system (smooth muscles, cardiac muscles, and glands).
        • The autonomic nervous system has sympathetic and parasympathetic divisions.

    Functions of the Nervous System

    • Sensory: Detects changes through sensory receptors.
    • Integrative: Analyzes sensory information, stores aspects, and makes decisions relating to behavior.
    • Motor: Responds to stimuli via effectors.

    Histology of Nervous Tissue

    • Neurons are electrically excitable.
    • They transmit nerve impulses.
    • Neuroglia are not electrically excitable.
    • They support and protect neurons.
    • There are 6 kinds of neuroglia (4 in CNS and 2 in PNS).
      • Astrocytes, Oligodendrocytes, Microglia, and Ependymal cells are types in the CNS.
      • Satellite cells and Schwann cells are types in the PNS.

    Neurons

    • Neurons are electrically excitable.
    • Neurons communicate with each other through action potentials or graded potentials.
    • Key features include the cell body, dendrites, and axon.
      • The axon may be myelinated for faster conduction.

    Structural Classification of Neurons

    • Based on the number of processes extending from the cell body.
      • Multipolar neurons have several dendrites and one axon.
      • Bipolar neurons have one dendrite and one axon.
      • Unipolar neurons have a single continuous process that serves as both axon and dendrite.

    Types of Neurons

    • Sensory/Afferent neurons-Convey information to the CNS.
    • Motor/Efferent neurons-Conveys action potential from the CNS.
    • Interneurons/Association neurons-Process sensory information and elicit motor response.

    Neuroglia

    • Neuroglia make up about half the volume of the nervous system.
    • Neuroglia can multiply and divide.

    Myelination of Neurons

    • Myelin is produced by Schwann cells (PNS) and oligodendrocytes (CNS).
    • Myelin increases the speed of nerve impulse propagation.
    • Myelinated axons are separated by nodes of Ranvier; this is part of saltatory conduction.

    Gray Matter vs. White Matter

    • Gray matter contains mainly neuron cell bodies and unmyelinated axons.
    • White matter contains mainly myelinated axons.

    Electrical Signals in Neurons

    • Excitable cells communicate through action potentials or graded potentials.
    • Action potentials allow communication over short and long distances.
    • Graded potentials allow communication over short distances.

    Action Potentials

    • Action potentials are rapid changes in membrane potential.
    • The phases include depolarization and repolarization.
    • Action potentials have absolute and relative refractory periods.
    • It depends on stimulus strength if an action potential occurs.

    Factors Affecting Propagation Speed

    • Axon diameter
    • Amount of myelination.
    • Temperature.

    Synapses

    • A synapse is the junction between neurons or between a neuron and an effector. -Electrical Synapses: Gap junctions allow direct communication. -Chemical Synapses: One-way transfer via neurotransmitter release.

    Postsynaptic Potentials

    • Excitatory postsynaptic potentials (EPSPs) are depolarizing potentials.
    • Inhibitory postsynaptic potentials (IPSPs) are hyperpolarizing potentials.

    Neurotransmitter Receptors

    • lonotropic receptors have a binding site and an ion channel.
    • Metabotropic receptors have a binding site that activates a G protein coupled to a separate ion channel.

    Neurotransmitters

    • Small molecule neurotransmitters, including acetylcholine, amino acids, biogenic amines, ATP, nitric oxide, and carbon monoxide.
    • Neuropeptides can act as neurotransmitters, such as substance P, enkephalins, endorphins, dynorphins, hypothalamic releasing and inhibiting hormones, angiotensin II, and cholecystokinin & neuropeptide Y.

    Summation

    • Summation is the combining of the effects of multiple stimuli. This can be spatial (multiple inputs) or temporal (multiple inputs over time).

    Neural Circuits

    • Neural circuits are functional groups of interconnected neurons.
    • Types of neural circuits include simple series, converging, diverging, reverberating, and parallel after-discharge circuits.

    Regeneration and Repair of Nervous Tissue

    • Neurons have limited ability to regenerate.
    • Plasticity and regeneration are factors that influence repair.
    • Repair is limited in the CNS but possible in the PNS.

    Neural Disorders

    • Disorders can include multiple sclerosis (autoimmune, progressive myelin sheath destruction), and depression (major depression, dysthymia, bipolar depression, and seasonal affective disorder).

    Other Neural Disorders

    • Other disorders include epilepsy, excitotoxicity (caused by high levels of glutamine in the interstitial fluid), and spinal cord compression. Also, traumatic injuries to the spinal cord such as monoplegia, paraplegia, hemiplegia and quadriplegia. Shingles is also listed as a disorder. Poliomyelitis is caused by the poliovirus and is transmitted from person to person.

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    Related Documents

    Nervous Tissue Principles of Anatomy and Physiology PDF
    The Spinal Cord and Spinal Nerves PDF
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    Description

    Test your knowledge on the main functions of the nervous system, including the roles of the central nervous system and peripheral nerves. Explore concepts like action potentials, ion channels, and the types of electrical signals in excitable cells. This quiz will help reinforce your understanding of neural communication.

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