ANA 111 Semester Test 3

• Superior mediastinum


  The area behind the manubrium of the sternum

  
• Borders of the superior mediastinum

  • Anterior: manubrium of the sternum
  • Posterior: vertebral bodies of T1-4
  • Superior: superior thoracic aperture
  • Inferior: imaginary plane @ T4/5
  • Laterally: mediastinal part of parietal pleura

  
• Contents of the superior mediastinum

  • Sternohyoid muscle
  • Thymus
  • Trachea
  • Oesophagus

  
• Arteries in the superior mediastinum

  • Aortic arch
  • Left subclavian
• Veins and lymphatic vessels in the superior mediastinum

  • Thoracic duct
  • Brachiocephalic veins
• Nerves in the superior mediastinum

  • Vagus nerve
  • Cardiac nerve
  • Phrenic nerve
• Lung apex


  • Projects upwards, 2.5 cm above clavicle (transverse process of T1)

  
• Anterior border of right lung

  • Extends from apex to sternoclavicular joint, to midline of sternal angle, downwards to xiphisternal joint

  
• Anterior border of left lung

  • Extends from apex to sternoclavicular joint, to midline of sternal angle, turns back to reach 6th costal cartilage

  
• Inferior border of lungs

  • Midclavicular line_ 6th rib
  • Midaxillary line_ 8th rib
  • Scapular line_ 10th rib
  • Adjacent to vertebral column _ 10th rib
• Posterior border of lungs

  • Lines between C7 and T10
  • Oblique fissure_ from root of spine of scapula, spinous process T2, joins the 6th rib
  • Horizontal fissure_ right lung, midsternal line, 4th costal cartilage to oblique fissure

  
• Hilum


  Gateway to the lungs
• Structures entering the lungs

  • Primary bronchus
  • 1 pulmonary artery
  • Bronchial artery and nerves
• Structures exiting the lungs

  • 2 pulmonary veins
  • Bronchial veins
  • Lymphatic vessels
• Relationships of root of lung

  • Situated at T5-T7
  • Anterior_ phrenic nerve
  • Posterior_ vagus nerve
  • Inferior_ empty pulmonary ligament

  
• Impressions on the root of the lung

  • Diaphragm
  • Heart
  • Blood vessels

  
• Arrangement of structures at the root of the lung

  • Pulmonary artery_ superior most
  • Superior pulmonary vein_ inferiormost
  • Bronchus_ middle posterior boundary

  
• Nasal septum


  A thin wall of cartilage and bone that separates the two sides of the nasal passages

  
• Components of the nasal septum


  • Septal cartilage
  • Vomer
  • Ethmoid bone
  • Nasal bones
  • Frontal bone
  • Maxillary bones
  • Palatine bones
  • Sphenoid bones

  
• Palatoglossal arch


  Covers palatoglossal muscle (in the front, in the tonsils)
• Palatopharyngeal arch


  Covers palatopharyngeal muscle (in the backish, next to the uvula)

  
• Palatine tonsils


  Located between the palatoglossal and palatopharyngeal arches

  
• Calvaria


  Refers to the skull cap (cranium without the facial bones)

  
• Cranium


  Refers to skull without the mandible

  
• Bones of the skull

  • 22 bones and 3 pairs of ossicles

  
• Neurocranium


  All the bones that make up the back of the skull

  
• Viscerocranium


  All the bones that make up the facial bones of the skull

  
• Maxillary sinuses


  Air filled sinuses that drain into the middle meatus

  
• Frontal sinuses


  Air filled sinuses that drain into the middle meatus via the frontonasal duct

  
• Ethmoid sinuses


  • Anterior cells_ drain into the middle meatus via the ethmoidal infundibulum
  • Middle cells_ drain into the middle meatus via the ethmoidal bulla
  • Posterior cells_ drain into the superior meatus
• Sphenoid sinuses


  Air filled sinuses that drain into the spheno-ethmoidal recess
• Functions of paranasal sinuses

  • Producing mucus to trap dust and bacteria
  • Aiding in resonance and sound production
  • Warming and humidifying the air
• Respiratory muscles


  • Diaphragm_ primary muscle of inspiration
  • External intercostal muscle_ helps expand the chest cavity during inspiration
  • Internal intercostal muscle_ helps decrease the size of the chest cavity during expiration
• External ear


  Consists of the pinna (auricle), ear canal (external auditory meatus), and tympanic membrane (eardrum)

  
• Structures of the external ear

  • Pinna (auricle)
  • Ear canal (external auditory meatus)
  • Tympanic membrane (eardrum)

  
• Nerves supplying the external ear

  • External ear_ vagus nerve & trigeminal nerve
  • Internal ear_ glossopharyngeal nerve

  
• Structures of the pinna

  • Tragus
  • Antitragus
  • Helix
  • Lobule
• Functions of the external ear


  • Collecting sound waves
  • Directing sound waves into the ear canal
  • Protecting the ear canal from dust, dirt, and other small objects

  
• Tympanic membrane


  A thin, translucent layer of tissue that separates the external ear canal from the middle ear

  
• Functions of the tympanic membrane

  • Transmitting sound energy to the middle ear bones (ossicles)
  • Separating the outer ear from the middle ear, protecting the inner ear from external noise
  • Helping to regulate air pressure in the middle ear