nine divisions

(noun)

An alternate system for dividing the abdominopelvic cavity into regions.

Related Terms

Examples of nine divisions in the following topics:

  • Abdominopelvic Regions

    • These divisions are often used to categorize the individual abdominal organs by their location and function and are used by clinicians to help diagnose the source of abdominal pain and determine appropriate treatment.
    • The most common divisions for the abdominopelvic region are the four quadrants and nine regions.
    • The nine divisions of the abdominopelvic region are smaller than the four quadrants, allowing for a more detailed discussion.
    • These divisions are marked by two parasagittal and two transverse planes centered around the navel.
    • The perineum (the area beneath the hypogastric region at the bottom of the pelvic cavity) is sometimes considered to be a tenth division in this system.

  • Brachial Plexus

    • The brachial plexus is divided into roots, trunks, divisions, cords, and branches.
    • Each trunk then splits in two, to form six divisions: The anterior divisions of the upper, middle, and lower trunks and the posterior divisions of the upper, middle, and lower trunks
    • These six divisions will regroup to become the three cords.
    • The cords are named by their position with respect to the axillary artery: The posterior cord is formed from the three posterior divisions of the trunks (C5-C8,T1), the lateral cord is the anterior divisions from the upper and middle trunks (C5-C7), and the medial cord is simply a continuation of the anterior division of the lower trunk (C8,T1)

  • Divisions of the Autonomic Nervous System

    • Sympathetic and parasympathetic divisions typically function in opposition to each other.
    • For an analogy, one may think of the sympathetic division as the accelerator and the parasympathetic division as the brake.
    • The sympathetic division typically functions in actions requiring quick responses.
    • The parasympathetic division functions with actions that do not require immediate reaction.

  • Parasympathetic Responses

    • Sympathetic and parasympathetic divisions typically function in opposition to each other.
    • The sympathetic division typically facilitates quick responses.
    • The parasympathetic division functions in a slower, stabler, and often inhibitory manner.
    • The parasympathetic nervous system may also be known as the parasympathetic division.
    • The parasympathetic nervous system, shown in blue, is a division of the autonomic nervous system.

  • Intercostal Nerves

    • The anterior divisions of the thoracic spinal nerves (T1-T11) are called the intercostal nerves.
    • The intercostal nerves are part of the somatic nervous system and arise from anterior divisions (rami anteriores, ventral divisions) of the thoracic spinal nerves from T1 to T11.
    • The intercostal nerves are distributed chiefly to the thoracic pleura and abdominal peritoneum and differ from the anterior divisions of the other spinal nerves in that each pursues an independent course without plexus formation.
    • The anterior division of the first thoracic nerve divides into two branches:
    • The anterior divisions of the second, third, fourth, fifth, and sixth thoracic nerves, and the small branch from the first thoracic, are confined to the walls of the thorax and are named thoracic intercostal nerves.

  • Divisions of the Skeletal System: Axial and Appendicular

    • The skeletal system is divided into two distinct divisions: the axial skeleton and the appendicular system.
    • It is a complex structure with two distinct divisions: the axial and the appendicular skeletons.

  • Parasympathetic (Craniosacral) Division

    • The parasympathetic division has craniosacral "outflow," meaning that the neurons begin at the cranial nerves (CN3, CN7, CN9, CN10) and sacral (S2-S4) spinal cord.
    • The parasympathetic nervous system, shown in blue, is a division of the autonomic nervous system.
    • Describe features of the parasympathetic division of the autonomic nervous system

  • Preganglionic Neurons

    • The sympathetic division has thoracolumbar "outflow", meaning that the neurons begin at the thoracic and lumbar (T1-L2) portions of the spinal cord.
    • The parasympathetic division has craniosacral "outflow", meaning that the neurons begin at the cranial nerves (CN3, CN7, CN9, CN10) and sacral (S2-S4) spinal cord.
    • The sympathetic division (thoracolumbar outflow) consists of cell bodies in the lateral horn of the spinal cord (intermediolateral cell columns) from T1 to L2.
    • Whereas in the parasympathetic division there is roughly a divergence factor of roughly 1:4, in the sympathetic division there can be a divergence of up to 1:20.
    • The parasympathetic division has craniosacral "outflow," meaning that the neurons begin at the cranial nerves (CN3, CN7, CN9, CN10) and sacral (S2-S4) spinal cord.

  • Overview of the Pituitary Gland

    • The pituitary gland is connected to the hypothalamus and secretes nine hormones that regulate body homeostasis.

  • Autonomic Interactions

    • Sympathetic and parasympathetic divisions typically function in opposition to each other (, red indicates sympathetic pathways and blue indicates parasympathetic pathways).
    • For an analogy, one may think of the sympathetic division as the accelerator and the parasympathetic division as the brake.
    • The sympathetic division typically functions in actions requiring quick responses.
    • The parasympathetic division functions with actions that do not require immediate reaction.
    • Describe the interactions between the sympathetic and parasympathetic divisions of the autonomic nervous system