Respiratory system Flashcards
(32 cards)
Why do cells need the respiratory system?
To get oxygen for respiration and remove carbon dioxide.
How is oxygen transported to cells?
Oxygen is taken into lungs → diffuses into blood → delivered to cells.
How is carbon dioxide removed from the body?
CO₂ from tissues is carried by blood to the lungs and exhaled.
What are the main organs of the respiratory system?
Nose, pharynx, epiglottis, larynx, trachea, bronchi, bronchioles, alveoli, lungs.
What happens to air in the nose?
It is warmed, humidified, and debris is trapped by mucus (lined with mucus producing mucous membranes).
What is the function of the pharynx?
Passage from nasal cavity to top of trachea.
What is the epiglottis and its function?
A cartilage flap that covers the trachea when eating to prevent choking.
What is the larynx?
Cartilage structure connecting pharynx trachea; contains vocal cords/mucous membranes that vibrate air to produce sound.
What supports the trachea and why?
C-shaped cartilage rings keep it open for airflow and mucus and cilia move particles up to pharynx to swallow.
bronchi?
2 Primary bronchi; Carry air from trachea into lungs; divide into smaller branches and get less c shaped cartilage more elastin/smooth muscle further from bronchi.
What are bronchioles?
Smaller airways made of smooth muscle and elastin; control airflow; still lined with mucus/cilia.
What are alveoli?
Tiny air sacs surrounded by capillaries; 1 cell thick walls; site of gas exchange.
How many lobes are in each lung?
Left lung: 2 lobes; Right lung: 3 lobes.
What is the mediastinum?
The space situated between the 2 pleural sacs.
What is the pleura?
A membrane covering the lungs and chest wall.
What is and does pleural fluid do?
thin layer between pleura; Lubricates lungs and helps them stick to chest wall during breathing to slide smoothly along the wall.
What causes ventilation (air movement in/out)?
Air pressure differences (high → low).
What happens during inspiration?
Diaphragm (move down) & intercostal muscles contract, lungs expand volume increases, aveolar pressure decreases.
What happens during expiration?
Diaphragm (go up) & muscles relax, lungs contract, air flows out.
Where does gas exchange occur?
In alveoli.
How does oxygen get into the deoxygenated blood?
Oxygen dissolves in alveolar moisture (high concentration) → diffuses into capillaries (low concentration).
How is CO₂ removed?
Diffuses from blood (high concentration of Co2) -> (low concentration) into alveoli.
What features help gas exchange in alveoli?
Large internal surface area of alveoli, hundreds of millions of alveoli, 1 cell thick, lung deep in body to prevent Evap of fluid that dissolve o2, concentration gradient.
What lifestyle/environmental factors affect gas exchange?
Smoking, air quality, pollutants.
