30 Questions
What is the primary function of the blood-air barrier in the lungs?
To prevent air bubbles from forming in the blood and blood from entering the alveoli
What is the approximate diffusion distance for oxygen and carbon dioxide in the pulmonary capillaries?
Less than the diameter of a red blood cell
What is the role of elastic fibers in the pulmonary interstitial space?
To maintain lung elasticity and prevent collapse
What is the origin of pulmonary macrophages?
Monocytes that have escaped from the blood capillaries
What is the purpose of the anastomosis between the bronchial and pulmonary capillary beds?
To ensure a constant supply of oxygenated blood to the lungs
What is the thickness of the blood-air barrier in the lungs?
0.2 to 2.5 µm
What is the primary function of the 'air-blood barrier' in the lungs?
To facilitate gas exchange between the alveolus and pulmonary capillaries
What is the approximate total surface area of the alveoli in both lungs?
70 m2
What is the primary role of Type II alveolar cells?
To secrete a surfactant
How many alveoli are approximately found in each lung?
300 to 400 million
What is the characteristic shape of Type I alveolar cells?
Squamous
What percentage of the total alveolar surface area is covered by Type I alveolar cells?
95%
What is the primary function of the pulmonary circulation?
To pump deoxygenated blood from the heart to the lungs
Which of the following veins receives blood from the right bronchial veins?
Azygos vein
What is the characteristic of the pulmonary artery in terms of pressure?
Lower pressure than that in the aorta
What is the direction of the right pulmonary artery?
Horizontally towards the hilum of the right lung
What is the origin of the pulmonary trunk?
Right ventricle of the heart
What is the path of the pulmonary trunk after it arises from the right ventricle?
It passes to the left side of the ascending aorta for about 5cm before bifurcating
What is the main characteristic of the left pulmonary artery?
It is shorter and narrower than the right pulmonary artery
What is the primary function of the pulmonary veins?
To carry oxygenated blood from the lungs to the heart
What is the location of the bronchomediastinal lymph nodes?
In the neck, alongside the trachea and esophagus
What is the primary function of the lobar arteries?
To carry blood to each lobe of a lung
Where do the bronchomediastinal lymph nodes drain into?
The thoracic duct on the left side
What is the characteristic of lymphatic vessels in the lung?
They are absent on the walls of alveoli
What is the primary function of the parasympathetic fibers in the pulmonary plexus?
Bronchoconstriction and secretomotor
During inspiration, which muscle is responsible for increasing the vertical thoracic diameter?
Diaphragmatic muscle
What is the primary mechanism of expiration in the respiratory cycle?
Recoil of the respiratory muscles
Which nerve provides the parasympathetic fibers to the pulmonary plexus?
Vagus nerve
What is the proportion of air entering the lungs due to the contraction of the intercostal muscles?
25%
What is the source of the sympathetic fibers in the pulmonary plexus?
Sympathetic trunk
Explore the process of gas exchange in the lungs, including the role of alveoli, pulmonary capillaries, and respiratory bronchioles. Learn about the structure and function of these critical components of the respiratory system.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
