5 respiratory system Flashcards
What structures make up the upper respiratory tract?
Nasal cavity, paranasal sinuses, pharynx, and larynx.
What is the main function of the upper respiratory tract?
To condition inspired air by warming, humidifying, and filtering it before it reaches the lungs.
What size particulates are filtered by the upper respiratory system?
Particulates larger than 10μm.
What structures are part of the lower respiratory tract?
Trachea, bronchi, bronchioles, alveolar ducts and sacs, and alveoli.
What is the main function of the lower respiratory tract?
Gas exchange and further removal of particulates.
What part of the brain controls the rhythm of breathing?
The medulla oblongata in the brainstem.
Which neurones are active during inspiration?
Inspiratory neurones.
What are the two main types of pleura?
Parietal pleura and visceral pleura.
Where is the apex of the lung located?
Just above the first rib, at the level of T1.
How many lobes does each lung have?
Right lung: 3 lobes; Left lung: 2 lobes.
What fissures separate the lobes in the lungs?
Right lung: Horizontal and oblique fissures; Left lung: Oblique fissure only.
What is the lingula of the lung?
A tongue-like projection on the left lung extending over the anterior surface of the heart.
What structures pass through the hilum of the lung?
Pulmonary artery, 2 pulmonary veins, main bronchus, bronchial vessels, nerves, lymphatics.
How can you distinguish bronchi, arteries, and veins at the hilum?
Bronchi have thick, cartilaginous walls; arteries have elastic walls; veins have thin, collapsible walls.
What are the surfaces of the lung?
Costal, mediastinal, and diaphragmatic.
What are the borders of the lung?
Anterior, posterior, and inferior.
: What is a potential space in the pleura?
A space that normally doesn’t exist but can fill with air/fluid in illness or injury.
What fluid is produced by the pleura and why?
Serous fluid; to lubricate the lungs and maintain surface tension during respiration.
What are the four parts of the parietal pleura?
Costal, mediastinal, diaphragmatic, and cervical pleura.
How far does the pleural cavity extend below the lungs during quiet respiration?
Midclavicular line: rib 8; Midaxillary line: rib 10; Posteriorly: vertebra T12.
Why is the right lung larger than the left?
Because the heart bulges more to the left, reducing space for the left lung.
What modifies the automatic rhythm of breathing?
Afferent input from chemoreceptors, the brain, and receptors in the lungs.
What are lung impressions and where are they found?
Marks left by adjacent mediastinal structures on the mediastinal surface of the lung.
Where are the right lung lobes mainly in contact with the thoracic wall?
Superior: anterior and neck;
Middle: anterior and lateral;
Inferior: posterior and inferior thoracic wall
Where is the oblique fissure located?
Posteriorly at T4, crosses 4th–5th intercostal spaces laterally, follows rib 6 anteriorly.
What are pleural recesses?
Potential spaces at the margins of the pleural cavity where lungs don’t extend in quiet breathing; allow expansion or fluid accumulation.
What are the two functions of serous pleural fluid?
Allows smooth lung movement and provides surface tension to keep lungs adhered to the chest wall.
Where do the visceral and parietal pleura become continuous?
At the root of the lung (hilum).
What is the appearance of healthy living lungs, and how can pollution affect this?
Soft, light, spongy; may have black deposits from polluted air.
🦴What are the three parts of the sternum?
🦴 Manubrium, sternal body, and xiphoid process.
🦴What part of the rib articulates with the vertebra?
🦴The head of the rib.
🦴 What are true ribs?
🦴Ribs 1–7; they articulate directly with the sternum via their own costal cartilages.
🦴What are false ribs?
🦴Ribs 8–12; they articulate indirectly or not at all with the sternum.
🦴What are floating ribs?
🦴 Ribs 11–12; they do not articulate with the sternum and are shorter and pointier.
🦴How many thoracic vertebrae are there and what do they articulate with?
🦴12; they articulate with the ribs and each other.
🫁 What is the diaphragm and where is it located?
🫁: A dome-shaped musculotendinous sheet separating thorax and abdomen.
🫁 What innervates the diaphragm?
🫁Right and left phrenic nerves (C3-C5) — “C3, C4, C5 keeps the diaphragm alive”.
🫁What level is the diaphragm highest and lowest?
🫁Highest at T9 (at rest), attached inferiorly at T12.
🫁What are the three major structures passing through the diaphragm?
🫁Aorta, inferior vena cava, oesophagus.
🫁What is the effect of diaphragm contraction?
🫁Flattens diaphragm, increases thoracic volume for inspiration.
💪What are the three layers of intercostal muscles?
💪External, internal, innermost.
💪 Where are intercostal neurovascular bundles located?
💪Along the lower border of each rib.
💪 What is the function of external intercostals?
💪Elevate ribs during inspiration.
💪What is the function of internal intercostals?
💪Depress ribs during active respiration.
💪 Where are innermost intercostals located?
💪Deep to internal intercostals, separated by neurovascular bundles.
🌬Name three accessory muscles of respiration.
🌬Sternocleidomastoid, pectoralis minor, scalene muscles.
🫁What is the ‘pump handle’ motion?
🫁Anteroposterior rib movement during breathing.
🫁What is the ‘bucket handle’ motion?
🫁 Lateral rib movement during breathing.
🌳Where does the trachea bifurcate?
🌳At vertebral level T4.
🌳What are the differences between the right and left primary bronchi?
🌳Right is wider, shorter, and more vertical.
🌳What do secondary (lobar) bronchi supply?
🌳Each lobe of the lung.
🌳What do tertiary (segmental) bronchi supply?
🌳Bronchopulmonary segments.
🌳Where do bronchioles first appear?
🌳Around the 12th generation of branching.
🌳What marks the beginning of the respiratory zone?
🌳Respiratory bronchioles.
🫁What is the primary site of gas exchange in the lungs?
🫁Alveoli.
🫁What is a lung lobule?
🫁 A cluster of alveoli supplied by one respiratory bronchiole.
🫁 What helps prevent alveolar collapse?
🫁Surfactant produced by type II pneumocytes.
🧬What type of epithelium lines the nasal cavity and sinuses?
🧬 Pseudostratified columnar epithelium with cilia and goblet cells.
🧬 How does epithelium change along the airways?
🧬 Becomes thinner and less ciliated distally.
🧬 What supports large bronchi?
🧬 Rings of hyaline cartilage.
🧬 What lines the bronchioles?
🧬 Simple ciliated columnar epithelium, few goblet cells.
🧬 What lines alveolar ducts?
🧬 Flattened epithelium.
🔬 What are type I pneumocytes?
🔬Thin, flat cells for gas diffusion, covering 90% of alveolar surface.
🔬What are type II pneumocytes?
🔬Rounded cells that secrete surfactant; also act as stem cells.
🔬What is the role of alveolar macrophages?
🔬Patrol alveolar spaces, phagocytose debris/pathogens.
🔬What protein gives lung tissue elasticity?
🔬Elastin.
⚠️ What is a pneumothorax?
⚠️Air in the pleural cavity causing lung collapse.
⚠️What is a haemothorax?
⚠️ Blood in the pleural cavity, usually from intercostal vessel injury.
⚠️What is a hydrothorax?
⚠️Accumulation of fluid in the pleural cavity.
⚠️What happens if surface tension in the pleura is broken?
⚠️Pleural cavity becomes a real space → lung collapses.
⚠️How is a collapsed lung treated?
⚠️Insertion of a chest drain to remove air/fluid.
