respiratory system it’s a gas!. respiratory system pathway of air: nose/mouth nasal/oral cavities...
TRANSCRIPT
Respiratory SystemPathway of Air:
• Nose/mouth• Nasal/oral
cavities• Pharynx• *Epiglottis• Larynx• Trachea• Bronchi• Bronchioles• Alveoli
Oral & Nasal Cavities & Pharynx
• Warm & moisten air to protect delicate lung tissue.• Sticky mucous lining &
mucous-covered hairs in nasal cavity filter particles from air.
Larynx & Voice
• Sound produced as 2 ligaments (vocal cords) vibrate when air passes through them.
• Pitch varies with tension of vocal cords – more tension = higher pitch
• Volume depends on amount of air forced past them – more air = greater volume.
• Laryngitis – inflammation of vocal cords due to overuse.
Airway
Trachea/bronchi • Made of rings of cartilage
(keeps airway open).• Lined with mucous membranes
(trap particles) and cilia (sweep particles up and out of airway).• Epiglottis closes trachea when
swallowing.• Bronchi branch into bronchioles
Lungs• Right is larger (3 lobes) than
left (2 lobes).• In thoracic cavity, lined w/
pleura (membranes that reduce friction.
• LARGE surface area.
Alveoli & CapillariesBronchioles terminate in dead-end sacs – alveoli – surrounded by a net of capillaries.
Gas Exchange• External Respiration -
Exchange of gases between atmosphere and blood by diffusion.
• Internal Respiration – Exchange of gases between blood and cells by diffusion.
• Diffusion happens when there is a concentration gradient (difference) in a fluid (gas or liquid).
• *The Respiratory System• Respiratory System
Oxygen & CO2 TransportIn Blood
97% of oxygen transported on hemoglobin in RBCs.67% of CO2 reacts w/ water to form carbonic acid, disassociates into bicarbonate ions (HCO3
-)
Mechanism of Breathing
• Diaphragm• Mechanism of Breathing• Mechanics of Breathing 2
Boyle’s Law – pressure exerted by a gas varies inversely with the volume of the gas.
Inspiration & Expiration
Respiratory System Review - Kahn Academy
Regulation of Breathing
Brain monitors the concentration of CO2 in the blood. Why not O2?
A: O2 is carried by hemoglobin inside RBCs, while CO2 is mostly carried in the plasma.
Disorders• Asthma –
inflammation of the lining of bronchioles causes reduced air flow.
• Emphysema – alveoli lose elasticity and rupture, reducing surface area and lung capacity.