The lungs are the principal organs of respiration located in the thoracic cavity. Each lung is cone-shaped with an apex, base, and borders. The right lung has three lobes separated by two fissures, while the left lung has two lobes separated by one fissure. The root of each lung contains the bronchus, pulmonary vessels and nerves and connects to the mediastinum. The lungs receive arterial blood supply from the pulmonary and bronchial arteries and venous drainage occurs through the pulmonary and bronchial veins. Lymphatic drainage is through vessels in the lungs that drain to tracheobronchial and bronchomediastinal lymph nodes. Nerve supply is from the vagus nerve and thoracic spinal nerves.

1. Lungs
Pradumn Vishwakarma
B.Optometry
CLGSO

2. Contents
TO DESCRIBE –
• Introduction Of Lungs
• External Feature
• Surface & Border Of Lungs
• Lobes & Fissure Of Lungs
• Hilum
• Root Of Lungs
• Arterial supply
• Venous Drainage
• Lymphatic Drainage
• Nerve Supply
• Difference b/w each lungs.

3. Introduction
• Lungs or Pulmones are the principal organs of respiration.
• In thoracic cavity separated by mediastinum& covered by
pleura.
• Texture– Spongy
• Color— Young- Brown
Adults-Molten Black (deposition of carbon particle)
• Weight— Right-600 gms
Left- 550 gms.
• Shape— Conical/Pyramidal

4. External Feature
Each lungs has following feature—
• Apex(conical,directed upward)
• Base(broader,directed downward)
• Three Border— Anterior, Posterior& Inferior
• Two Surface—Coastal & Medial
Coastal Surface is convex ,directed outward

6. Each Lung is having Lobes separated by fissures —
Right-3
Left-2

7. Apex
• Rounded/blunt superior end of the lung,
• Lies above the level of ant. end of 1st rib
• Reaches1-2cm above medial 1/3rd of clavicle
• Covering—
• Cervical Pleura
• Suprapleural Membrane.

8. Base
• Semi lunar and concave
• Rests on diaphragm (diaphragmatic surface)
• Right sided dome is higher then left

9. Borders
 Anterior- Thin Shorter ,Vertical
• Present cardiac notch in left lung.
• Below It Lingula is present.
 Posterior -Thick and rounded,
• Spine of C7 vertebra to the spine of T10 vertebra
 Inferior-Semi lunar in shape ,
• Separates the costal and medial surfaces.

10. Surfaces
Coastal-Large, smooth, and convex
• Covered by costal pleura and endothoracic fascia.
Medial- Posterior (Vertebral )
Anterior (Mediastinal)
• Posterior Part-vertebral column, posterior intercostal vessels,
and greater and lesser splanchnic nerves.

11. Mediastinal surface of the
right lung
Mediastinal surface of the
left lung
Right atrium Left ventricle
Superior and inferior vena
cava
Ascending aorta
Azygos vein Arch of aorta and descending
thoracic aorta
Right brachiocephalic vein Left subclavian and left
common carotid arteries
Esophagus and trachea Esophagus and thoracic duct
Three Neural Structure Four neural structures
•Rt.Phrenic nerve
•Rt. Splenhnic Nerve
•Rt.Sympathetic Nerve
•Lt.Phrenic Vein
•Lt.Vagus nerve
•Left recurrent pharyngeal
nerve
• Left sympathetic chain
Anterior Part

12. Right Left

13. Lobes & Fissure
• The right lung is divided into three lobes—
Superior, middle, and inferior
*By two fissures—(a) an oblique fissure and
(b)a horizontal fissure.
• The left lung is divided into two lobes—
(a) superior and
(b) inferior
*By an oblique fissure

16. Hilum
• This is large depressed area near medial surface.
• Through which structures enter or leave the lung.

17. Root Of Lung
• Short broad pedicle.
• Connecting the medial surface of the lung with the
mediastinum.
• Covered by tubular sheath derived from the mediastinal
pleura.
• The root of lung lies opposite the bodies of T5, T6,
and T7 vertebrae

18. Components
1. Principal bronchus in the left lung,
and eparterial and hyparterial bronchi in the right lung.
2. Pulmonary artery.
3. Pulmonary veins (two in number).
4. Bronchial arteries (one on the right side and two on the
left side).
5. Bronchial veins.
6. Lymphatics of the lung.
7. Anterior and posterior pulmonary plexuses of the
nerves.

20. Arrangement Of Structure
1. From before backwards—
• (a) Pulmonary vein (superior)
• (b) Pulmonary artery
• (c) Bronchus
2. From above downwards—
Right side Left side
• Eparterial bronchus Pulmonary artery
• Pulmonary artery Left principal bronchus
• Hyparterial bronchus Inferior pulmonary vein
• Inferior pulmonary vein

21. Arterial Supply Of Lungs
• The lungs are supplied by two sets of arteries,
1. Bronchial arteries.
2. Pulmonary arteries.

22. Venous Drainage
• The venous blood from lungs is also drained by two sets of
veins,
1. Bronchial veins.
2. Pulmonary veins

23. Lymphatic Drainage
• The lymph from the lung is drained by two sets of lymph
vessels
1. Superficial vessels.
2. Deep vessels
*The lymphatic drainage of the lung is clinically important
because lung cancer spreads by lymphatic path.
*All the lymph is drained into tracheobronchial lymph nodes
(located at the hilum), which in turn drain into
bronchomediastinal lymph nodes.

25. Nerve Supply
• The lung is supplied by—
 Parasympathetic - derived from the vagus nerve .
 Sympathetic nerve fibres- derived from T2 to T5 spinal
segments
*Both provide motor supply to the bronchial muscles and
secretomotor supply to the mucous glands of the bronchial
tree.

26. Difference B/W Left and Right Lung

27. References
• Textbook of Anatomy By Vishram Singh.
• Textbook of Anatomy By BD Chaurasiya.
• Diagram From Ken hub.