Nervous System - Neuroanatomy

» Know that the roots connect the spinal nerves to a segment of the spinal cord 1. posterior (dorsal) root - contains only sensory axons 2. anterior (ventral) root - contains axons of somatic motor neurons » Know the function of the spinal cord in the human body; there are two major functions: 1. biological highways or “pathways” for nerve impulse conduction (= white matter) 2. site of integration of reflexes (= gray matter)» Know that a reflex is a very fast involuntary sequence of actions in the body in response to a particular stimulus; some reflexes, e.g. the eye lid or patellar knee jerk reflex, are inborn and don’t have to be trained- be able to name the difference between a spinal and a cranial reflex  » Know the different basic components and the path of nerve impulse in a typical reflex arc; the components are: 1. Sensory receptor - located at distal ends of sensory neurons 2. Sensory (afferent) neuron - axonal conduction of nerve impulse from receptor to the gray matter of the spinal cord 3. Integrating center - interaction of synapse of sensory neuron with a motor neuron; sometimes including interneurons 4. Motor (efferent) neuron - axonal conduction of nerve impulse from spinal cord to responding area of the body, e.g. a skeletal muscle 5. Effector - the part of the body that responds to the (efferent) nerve impulse of the motor neuron - can be a skeletal muscle (= somatic reflex), or cardiac muscle, smooth muscle or gland (= visceral reflex)» Know the important examples of reflexes of the human body, which are: 1. Patellar (or knee jerk) reflex - assesses the function of the S1 and S2 spinal nerves; - sensory receptors are in the quadriceps femoris muscle; - effector muscle is the quadriceps femoris; 2. Plantar reflex - another important neurological test which probes the integrity of the corticospinal tract (= major voluntary motor tract); - elicited by stimulating receptors in the sole of the foot; - effector muscles are flexor muscles in the toes which flex and move closer together; - damage to the corticospinal tract elicits the “Babinski’s sign”; - as a consequence the toes flare and the great toe moves upward!

» Know that the roots connect the spinal nerves to a segment of the spinal cord
        1. posterior (dorsal) root
                - contains only sensory axons
        2. anterior (ventral) root
                - contains axons of somatic motor neurons
» Know the function of the spinal cord in the human body; there are two major
   functions:
        1. biological highways or “pathways” for nerve impulse conduction
            (= white matter)
        2. site of integration of reflexes (= gray matter)
» Know that a reflex is a very fast involuntary sequence of actions in the body in
   response to a particular stimulus; some reflexes, e.g. the eye lid or patellar
   knee jerk reflex, are inborn and don’t have to be trained
- be able to name the difference between a spinal and a cranial reflex

» Know the different basic components and the path of nerve impulse in a typical
   reflex arc; the components are:
        1. Sensory receptor
                - located at distal ends of sensory neurons
        2. Sensory (afferent) neuron
                - axonal conduction of nerve impulse from receptor to the gray matter of the spinal cord
        3. Integrating center
                - interaction of synapse of sensory neuron with a motor neuron; sometimes
                   including interneurons
        4. Motor (efferent) neuron
                - axonal conduction of nerve impulse from spinal cord to responding area of
                  the body, e.g. a skeletal muscle
        5. Effector
                - the part of the body that responds to the (efferent) nerve impulse of the motor neuron
                - can be a skeletal muscle (= somatic reflex), or
                  cardiac muscle, smooth muscle or gland (= visceral reflex)
» Know the important examples of reflexes of the human body, which are:
        1. Patellar (or knee jerk) reflex
            - assesses the function of the S1 and S2 spinal nerves;
            - sensory receptors are in the quadriceps femoris muscle;
            - effector muscle is the quadriceps femoris;

        2. Plantar reflex
            - another important neurological test which probes the integrity of the
               corticospinal tract (= major voluntary motor tract);
            - elicited by stimulating receptors in the sole of the foot;
            - effector muscles are flexor muscles in the toes which flex and move closer
              together;
            - damage to the corticospinal tract elicits the “Babinski’s sign”;
                - as a consequence the toes flare and the great toe moves upward!