Comparison between tract and nerve

  Comparison between tract and nerve Nerve Nerve contain bundle of axons (nerve fibers) in the peripheral nervous system (PNS) that transmits signals between the central nervous system (CNS) and other parts of the body. It is the most important part of peripheral nervous system Location: Peripheral nervous system. Structure: Made of axons, connective tissue layers (endoneurium: axon is surrounded by it , perineurium: bundle of axons are surrounded by it, epineurium: whole nerve trunk is surrounded by it), and blood vessels. It gets myelination by Schwann cell   Function: Carries sensory signals to the CNS (afferent) from peripheral part of body or motor signals carry from from the CNS (efferent) to target organs like skeletal muscle, cardiac muscle, smooth muscle or glands Example: Sciatic nerve, median nerve, except optic nerve (though optic nerve is technically part of CNS in develop...

Difference between two tiny muscles of middle ear cavity : tensor tympani and stapedius muscles

Difference between two tiny muscles of middle ear cavity : tensor tympani and stapedius muscles



Topics

Tensor tympani

Stapedius
Origin :
Both cartilaginous and bony part of auditory tube
Interior of pyramid which situated on the posterior wall of middle ear cavity
Insertion
Medial aspect of neck of malleus
Posterior aspect of neck of stapes
Blood supply
Superior tympanic artery branch of middle meningeal artery
Posterior auricular artery , a branch of external carotid artery
Anterior tympanic artery and middle meningeal artery
Nerve supply
Nerve to medial pterygoid branch of mandibular division of trigeminal nerve
Facial nerve
Nerve related with ganglia
Nerve to medial pterygoid passes through otic ganglia
None
Functions
It tenses the tympanic membrane and push the base of stapes more tightly into the fenestra vestibule
Draws the stapes laterally and opposes the action of tensor tympani muscle (which pushes the stapes more tightly into the fenestra vestibuli)

Popular posts from this blog

Difference between lumbar and sacral splanchnic nerve

Difference between greater and lesser splanchnic nerve

Difference between anterior and posterior part of rectus sheath Topics Anterior part of rectus sheath Posterior part of rectus sheath Above costal margin This part of rectus sheath is only formed by single aponeurosis. The aponeurosis of External oblique abdominis No rectus sheath Related with costal cartilage From costal margin to arcuate line This part of rectus sheath is formed by two aponeurosis. The aponeurosis of External oblique abdominis and anterior layer of aponeurosis of internal oblique abdominis This part of rectus sheath is formed by two aponeurosis. The aponeurosis of External oblique abdominis and posterior layer of aponeurosis of internal oblique abdominis Below the arcuate line (this line is situated midway between umbilicus and upper surface of pubis symphysis ) This part of rectus sheath is formed by three aponeurosis. The aponeurosis of External oblique abdominis, internal oblique abdominis and transverses abdominis No rectus sheath Related with fascia transversalis