Introduction and Anatomy of Lungs, Airways and Blood Supply Flashcards
(42 cards)
What is pulmonary blood flow/circulation?
Pulmonary artery carries deoxygenated blood away from the heart to lungs and pulmonary vein returns oxygenated blood back to heart. Delivers CO2 to lungs and picks up O2.
What is systemic blood flow/circulation?
Carries oxygenated blood away from heart to peripheral tissues and returns deoxygenated blood back to heart.
Main anatomical features of the airways
Nose, mouth, pharynx, epiglottis, larynx, trachea
What happens to air at the nose?
Air enters, cilia and mucous trap particles, warmth of nose moistens air. Bigger surface area to breathe in through nose than mouth.
What happens to air at the mouth?
Enters but doesn’t get moistened/saturated as much as in the nose.
What happens at pharynx?
Air moves down here, also called throat
What is the epiglottis?
Small flap of tissue that folds over trachea when swallowing to prevent food entering the lungs
What is the larynx?
Voice box, contains vocal cords which vibrate to produce sound on expiration
Features of trachea
Made of stiff rings of C-shaped cartilage rings that support it. They maintain patency of the upper airway. Patent = open.
Gross anatomical features of the lungs
Right/left.
Right has 3 lobes (superior, middle, inferior). Horizontal fissure separates superior and middle; oblique fissure separates middle and inferior. Left has 2 lobes (superior, inferior). Oblique fissure separates them.
What happens to trachea at T4?
It bifurcates to right and left bronchus. Right bronchus branches to 3 secondary bronchi; left bronchus branches to 2. Secondary bronchi then branch again to tertiary bronchi (bronchioles) and these lead to alveoli.
How many times does each bronchus branch before terminating into a cluster of alveoli?
Around 23 times (24 divisions of trachea until alveoli)
What’s different about the right and left bronchus?
Right bronchus splits at a greater angle than the left, it’s almost vertically underneath the trachea so aspirated foreign bodies commonly get stuck here.
What does upper respiratory tract consist of?
Nose, mouth, pharynx, epiglottis, larynx.
What does lower respiratory tract consist of?
Trachea, bronchus, lungs.
What do bronchioles not have?
No cartilage
Functions of respiratory system
Gas exchange
Acid base balance
Protection from infection
Communication via speech
What gas exchange occurs in respiratory system?
Oxygen added to blood from air, carbon dioxide removed from blood into air. CO2 build up is toxic.
What’s the most important function of the respiratory system?
Gas exchange because it allows oxygen to be taken in and used in cellular respiration to make energy and CO2 as a waste product.
What is acid base balance?
Regulation of body pH. Maintains a pH of 7.4 of extracellular fluid.
How does the respiratory system protect from infection?
Lymphoid tissue around respiratory tract to protect from infection, scans the air we’re breathing and activates immune response.
How does the respiratory system allow us to talk?
Air vibrates vocal chords for speech, speaking occurs on expiration.
Points of gas exchange between respiratory and cardiovascular system
In alveoli of lungs - O2 moves from inspired air to blood, CO2 moves from blood to air through expiration.
In systemic capillaries - O2 moves from blood to cells, CO2 moves from cells to blood.
What are the different classes of airways?
Trachea, primary/secondary bronchus, bronchioles (tertiary), alveoli
