Respiratory System 4 Flashcards
4 respiratory system functions
- Gas exchange CO2 and O2
- Warming, cooling & moistening air
- Removal of inhaled particles immunity
- Voice production and olfaction
Air flow route - 8 structures
- Nose
- Paranasal sinuses
- Pharynx (throat)
- Larynx (voice box)
- Trachea
- Bronchi
- Bronchioles
- Alveoli
3 types of respiration
- External - blood an lung ‘ventilation’
- Internal - blood and cells
- Cellular - ATP
Compare External and Internal reputation
External - blood and lungs - ‘ventilation’
Internal - blood and cells
Lining of respiratory tract
Ciliated epithelial membrane with mucus-secreting goblet cells
Mucociliary escalator
- Mucus traps inhaled particles - mucus is anti microbial
- Cilia move particles towards the oesophagus where it can be coughed up or swallowed
Purpose of mucociliary escalator
Protect lungs from pathogens
What are nasal concha (turbinates)
Shelves that increase surface area and trap water during exhalation
4 functions of nasal cavity
Filtering air
Warming air
Humidification
Sneezing reflex
Olfactory function
2 paranasal sinuses
Frontal
Maxillary
Ethmoid
Sphenoid
4 functions of paranasal sinuses
- Resonance of speech
- Lightening cranial mass
- Drains tears
- Humidifying air
Describe pharynx (throat)
Straight muscular tube connects nose and throat, 13cm long
3 sections of pharynx
Nasopharyngeal
Oropharynx
Laryngopharynx
Eustacian tubes function
Equalisation of pressure in middle ear
Adenoids
Nasopharyngeal to tonsils
4 Pharynx function
Passageway
Warming humidifying
Taste
Hearing
Equalisation of pressure
Immune - to cults
Speech
How laryngeal muscles alter tone
Relaxed - low
Contracted - high
Hormone thickens and lowers vocal chords
Testosterone
4 larynx functions - voice box
- Production of sound
- Protection - epiglottis
- Air passageway
- Warming and humidifying
Trachea description
Windpipe 12cm long
Incomplete c shaped rings of hyaline cartilage
What does the trachea respond to
Sympathetic - dilation
Parasympathetic- constriction
Cough reflex 6 stages
- Irritation of mucus membrane
- Nerve endings stimulated
- Vegus nerve signal to the brain stem
- Deep inhalation + closure of glottis
- Contracts muscles (abdominal & respiratory)
- Forced removal
4 trachea functions
- Air flow
- Mucociliary escalator
- Cough reflex
- Warming & humidifying air
How do trachea and bronchi connect
Trachea divides into left and right bronchi at T5
Internal ridge I called the carina
Which bronchi is more vertical, shorter an wider
Right
Which lung is an aspirated object more likely to enter
Right
Nervous system impact on air to bronchi
Sympathetic- bronchodilation
Parasympathetic - bronchi constriction
4 Alveoli maximised gas exchange
- Large surface area 80m2
- Walls thin
- Surrounded blood capillaries
- Surface moist
Alveolar gas exchange
Air in and out of sack
Venus blood in - co2 out
O2 in and oxygenated blood out
Alveolar cell types
Type I
Simple epithelial cells
Thin gas exchange
90% surface area
Type II
Excrete pulmonary surfactant
Macrophages
Role of alveaolar pulmonary surfactant
Reduces surface tension
Allows gasses to diffuse
Lung development in premature babies
Pulmonary surfactant not produced until 20-24 weeks
Which organ separates the lungs
Heart
4 lung surfaces
Apex - above clavicle
Base - over diaphragm
Coastal
Neil
How many lobes does the lungs have
Right 3
Left 2
Role of pleura
Serous membrane surrounds the lungs and prevents friction
2 phases of ventilation
- Inhalation
- Exhalation
2 areas where breathing comes from
- Abdominal (diaphragmatic) breathing
- Upper ribs
2 primary muscles for ventilation
- Intercostal (between ribs)
- Diaphragm
2 secondary muscles of ventilation
Trapezius
Sternocleudomastoid
Scalenes
Pathology that can lead to over use of secondary ventilation muscles
Asthma
Ventilation key facts
Inhalation - active
Air down a pressure gradient
Exhalation - passive
Elastic recoil of the lungs
Define tidal volume
Normal volume of air that enters lungs which no extra effort is applied
Normally 500ml
Average capacity of human lungs
6 litres
2 factors that contribute to larger lung volumes
Men
Taller
Non-smokers
Athletes
Living at higher altitudes
Why no difference between inspired and expired nitrogen gas?
Doesn’t bind to haemoglobin.
Not used in the blood
Which blood cell transports oxygen around the body
Red blood cells
98.5% oxygen in blood is transported by haemoglobin
3 ways carbon dioxide is transported
70% in plasma bicarbonate
23% RBC
7% dissolved in plasma
Role of bicarbonate buffer reaction
In blood CO2 combines with after to produce carbonic acid H2CO3
Carbonic can us unstable and decomposes to bicarbonate and H+
Hydrogen exhaled and excreted
Bicarbonate buffers the acidity
What causes respiratory acidosis?
CO2 dissolves in blood causes an increase in H+ ions
Also exercise lactic acid
And ketoacids
How does ventilation contribute to acidity of body fluids
Lowers acidity via exhalation of CO2
Oxyhaemoglobin
Plenty of oxygen bound to haemoglobin
Deoxyhaemoglobin
Haemoglobin lacks oxygen
Regulating blood Ph formula
Carbon dioxide + water =
Carbonic acid =
Bicarbonate + acid
