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Anatomy - NEETMDS- courses
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Anatomy

The Soft Palate

  • This is the posterior curtain-like part, and has no bony support. It does, however, contain a membranous aponeurosis.
  • The soft palate, or velum palatinum (L. velum, veil), is a movable, fibromuscular fold that is attached to the posterior edge of the hard palate.
  • It extends posteroinferiorly to a curved free margin from which hangs a conical process, the uvula (L. uva, grape).
  • The soft palate separates the nasopharynx superiorly and the oropharynx inferiorly.
  • During swallowing the soft palate moves posteriorly against the wall of the pharynx, preventing the regurgitation of food into the nasal cavity.
  • Laterally, the soft palate is continuous with the wall of the pharynx and is joined to the tongue and pharynx by the palatoglossal and palatopharyngeal folds.
  • The soft palate is strengthened by the palatine aponeurosis, formed by the expanded tendon of the tensor veli palatini muscle.
  • This aponeurosis attaches to the posterior margin of the hard palate.

Intrinsic Muscles of the Tongue

The Superior Longitudinal Muscle of the Tongue

  • The muscle forms a thin layer deep to the mucous membrane on the dorsum of the tongue, running from its tip to its root.
  • It arises from the submucosal fibrous layer and the lingual septum and inserts mainly into the mucous membrane.
  • This muscle curls the tip and sides of the tongue superiorly, making the dorsum of the tongue concave.

 

The Inferior Longitudinal Muscle of the Tongue

  • This muscle consists of a narrow band close to the inferior surface of the tongue.
  • It extends from the tip to the root of the tongue.
  • Some of its fibres attach to the hyoid bone.
  • This muscle curls the tip of the tongue inferiorly, making the dorsum of the tongue convex.

 

The Transverse Muscle of the Tongue

  • This muscle lies deep to the superior longitudinal muscle.
  • It arises from the fibrous lingual septum and runs lateral to its right and left margins.
  • Its fibres are inserted into the submucosal fibrous tissue.
  • The transverse muscle narrows and increases the height of the tongue.

 

The Vertical Muscle of the Tongue

  • This muscle runs inferolaterally from the dorsum of the tongue.
  • It flattens and broadens the tongue.
  • Acting with the transverse muscle, it increases the length of the tongue.

The Meatus of the Nose

Sphenopalatine Recess

  • This space is posterosuperior to the superior concha.
  • The sphenoidal sinus opens into this recess.

Superior Meatus

  • This is a narrow passageway between the superior and middle nasal conchae.
  • The posterior ethmoidal sinuses open into it by one or more orifices.

Middle Meatus

  • This is longer and wider than the superior one.
  • The anterosuperior part of this meatus lead into a funnel-shaped opening, called the infundibulum, through which the frontonasal duct leads to the frontal sinus.
  • There is one duct for each frontal sinus and since there may be several, there may be several frontonasal ducts.
  • When the middle concha is removed, rounded elevation called the ethmoidal bulla (L. bubble), is visible
  • The middle ethmoidal air cells open on the surface of the ethmoidal bulla.
  • Inferior to this bulla is a semicircular groove called the hiatus semilunaris.
  • The frontal sinus opens into this hiatus anterosuperiorly.
  • Near the hiatus are the openings of the anterior ethmoid air cells.
  • The maxillary sinus also opens into the middle meatus.

Inferior Meatus

  • This is a horizontal passage, inferolateral to the inferior nasal concha.
  • The nasolacrimal duct opens into the anterior part of this meatus.
  • Usually, the orifice of this duct is wide and circular.

Appendicular Skeleton
Upper extremity
•    Shoulder-clavicle and scapula

Clavicle
    Articulates with the manubrium at the sternal end
    Articulates with the scapula at the lateral end
    Slender S-shaped bone that extends horizontally across the upper part of the thorax
    
Scapula

    Triangular bone with the base upward and the apex downward
    Lateral aspect contains the glenoid cavity that articulates with the head of the humerus
    Spine extends across the upper part of the posterior surface; expands laterally and
    forms the acromion (forms point of shoulder) 
    Coracoid process projects anteriorly from the upper part of the neck of the scapula
    
Arm (humerus)

Consists of a shaft (diaphysis) and two ends (epiphyses)
Proximal end has a head that articulates with the glenoid fossa of the scapula
Greater and lesser tubercles lie below the head

Intertubercular groove is located between them; long tendon of the biceps attaches here
Surgical neck is located below the tubercles

    o    Radial groove runs obliquely on the posterior surface; radial nerve is located here

    o    Deltoid muscles attaches in a V-shaped area in the middle of the shaft. called the deltoid tuberosity
    
Distal end has two projections. the medial and lateral epicondyles
Capitulum-articulates with the radius
Trochlea-articulates with the ulqa

Forearm

Radius
Lateral bone of the forearm
Radial tuberosity is located below the head on the medial side
Distal end is broad for articulation with the wrist: has a styloid process on its lateral side

Ulna

    Medial side of the forearm
    Conspicuous part of the elbow joint (olecranon)
    Curved surface that articulates with the trochlea of the humerus is the trochlearnotch
    Lateral ide is concave (radial notch); articulates with the head of the radius Distal end contains the styloid process 
    Distal end contains the styloid process

Hand

Carpal bones (8)
    Aranged in two rows of four
    Scaphoid. lunate. triquetral. and pisiform  proximal row); trapezium. trapezoid.
    capitate. and hamate (distal row)
    
Metacarpal bones (5)
    Framework of the hand
    Numbered 1 to 5 beginning on the lateral side
    
Phalanges (14)
    Fingers
     Three phalanges in each finger; two phalanges in the thumb

 

Innervation of the Pharynx

  • The motor and most of the sensory supply of the pharynx is derived from the pharyngeal plexus of nerves on the surface of the pharynx.
  • The plexus is formed by pharyngeal branches of the vagus (CN X) and glossopharyngeal (CN IX) nerves, and by sympathetic branches for the superior cervical ganglion.
  • The motor fibres in the pharyngeal plexus are derived from the cranial root of accessory nerve (CN XI), and are carried by the vagus nerve to all muscles of the pharynx and soft palate.
  • The exceptions are stylopharyngeus (supplied by CN IX) and the tensor veli palatini (supplied by CN V3).

The Skeleton of the Nose

  • The immovable bridge of the nose, the superior bony part of the nose, consists of the nasal bones, the frontal processes of the maxillae, and the nasal part of the frontal bones.
  • The movable cartilaginous part consists of five main cartilages and a few smaller ones.
  • The U-shaped alar nasal cartilages are free and movable.
  • They dilate and constrict the external nares when the muscles acting on the external nose contract.

 

The Nasal Cavities

  • The nasal cavities are entered through the anterior nares or nostrils.
  • They open into the nasopharynx through the choanae.

 

The Roof and Floor of the Nasal Cavity

  • The roof is curved and narrow, except at the posterior end.
  • The floor is wider than the roof.
  • It is formed from the palatine process of the maxilla and the horizontal plate of the palatine bone.

 

The Walls of the Nasal Cavity

  • The medial wall is formed by the nasal septum; it is usually smooth.
  • The lateral wall is uneven owing to the three longitudinal, scroll-shaped elevations, called the conchae (L. shells) or turbinates (L. shaped like a top).
  • These elevations are called the superior, middle and inferior conchae according to their position.
  • The superior and middle conchae are parts of the ethmoid bone, whereas the inferior conchae are separate bones.
  • The inferior and middle conchae project medially and inferiorly, producing air passageways called the inferior and middle meatus (L. passage). Note: the plural of "meatus" is the same as the singular.
  • The short superior conchae conceal the superior meatus.
  • The space posterosuperior to the superior concha is called the sphenoethmoidal recess.

  • The palate has a rich blood supply from branches of the maxillary artery.

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