Flashcards in Respiratory System Deck (97):
Why do we breath?
To gain oxygen for metabolism
To get rid of carbon dioxide
What is the equation for energy production?
Oxygen + glucose = energy (ATP) + water + carbon dioxide
What are the structures of the respiratory system?
Pons & medulla oblongata (respiratory control areas of the brain)
In order where does air pass through on its way to the lungs?
Secondary (lobar) bronchi
What is the name of the two membranes that cover the lungs?
What is the name of the inner pleural membrane & what is it attached to?
Attached to the surface of the lungs
What is the name of the outer pleural membrane & what is it attached to?
Attached to the inside of the chest wall.
What happens to the lungs during breathing due the arrangement of the pleural membranes?
As the chest walks move, the lungs follow.
What fills the gap between the visceral & parietal membranes?
What is the function of pleural fluid?
Name the respiratory muscles?
Internal & external intercostal muscles (between ribs)
Accessory muscles of the neck and abdomen (scalenes-neck) (oblique abdominals)
What is the anatomical name for the nostrils?
What lines the naval cavity & what is there purpose?
Coarse hairs to trap entering particles
What are the 3 shelves in the nasal cavity called & what is their purpose?
Create turbulence & also catch particles
What type of epithelium lines the nasal cavity?
What type of cells lines the nasal cavity?
Columnar ciliated cells interspersed with goblet (mucus-secreting) cells.
What does the nasal cavity do do the air that passes through?
Cleans the air
What is the pharynx?
Throat & the common tube for food & air
Hat are the 3 parts of the pharynx?
What links the pharynx to the middle ear?
What lines the pharynx?
What does the pharynx divide ventrally into?
What foes the pharynx divide dorsally into?
What covers the trachea during swallowing?
What is the anatomical name of the voice box?
What does the larynx consist of?
Cartilage & vocal folds
How does the larynx work?
Folds vibrate as air passes over them during expiration to produce sounds
What does the larynx mark the end of?
Upper respiratory tract
What is the anatomical name for the wind pipe?
How big is the trachea?
Tube around 12cm long & 1.8cm in diameter
What lines the trachea?
How does the preparation of air continue in the trachea?
How dies the cell shape change in the trachea?
What supports the trachea?
Rings of cartilage (c-rings)
Why are c-rings incomplete posteriorly?
To allow room for the oesophagus to expand
What is the name of the place where the trachea divide into the 2 main bronchi (primary bronchi)
At what level is the carina located?
Level of the 5th thoracic vertebrae
Why is the mucus lining of the trachea highly sensitive?
So cough reflexes are triggered easily
How many generations are there in the respiratory tree?
What generation is the trachea in the respiratory tree?
What generation are the primary bronchi in the respiratory tree?
What generation are the secondary (lobar) bronchi in the respiratory tree?
What generations are the bronchioles in the respiratory tree?
What are the final generations of the respiratory tree?
Name all the generations of the respiratory tree?
Secondary (lobar) bronchi
What changes occur in the small bronchi & bronchioles?
Wall of the airway changes
What does the bronchus have more of?
What does the bronchiole have more of?
More blood vessels
What within the airways walls allows its diameter to alter?
What determines airway resistance?
Diameter of airways
What is bronchoconstriction?
Narrowing of the airways
What causes bronchoconstriction?
Parasympathetic stimulation & increase in airway resistance
What is bronchodilation?
Widening of the airways
What does bronchodilation reduce?
What causes bronchodilation?
Adrenaline & noradrenaline secreted by adrenal medulla
What is the alveoli?
Site of gas exchange
What are the alveoli & what are they lined with?
Tiny sacs lined by simple cuboidal/squamous epithelium
Why are the alveoli lined with simple cuboidal/squamous epithelium?
Easier for the air to pass the membrane
What is each alveolus surrounded by?
About 100 pulmonary capillaries
What are the pulmonary capillaries lined by & what is this sometimes called?
What does the alveoli create to aid gas exchange?
Huge surface area
What does the pulmonary trunk carry?
Deoxygenated blood from heart to lungs
What do the pulmonary veins carry?
Oxygenated blood from lungs to heart
How does gas exchange happen in the alveoli?
Co2 diffuses down its concentration gradient from the deoxygenated capillary blood into the alveolar air. It is then expelled from the body during expiration
What regulates the basic respiratory rhythm?
Medulla oblongata & pons (brainstem)
How does the medulla oblongata regulate basic respiratory rate?
Houses neurones that fire an intrinsic rhythm that coincides with the respiratory cycle
How do the respiratory neurones work in relation to respiratory rhythm?
Inspiratory neurone & expiratory neurones fire alternatively
What does the pons appear to play a role in regarding respiration?
Regulation of respiratory rate & depth
Why do we breath?
Inhale oxygen & exhale Co2 to aid normal cell function
What does breathing maintaining?
Normal arterial blood gas (ABG) levels
What can too much Co2 cause?
pH to fall
What does insufficient oxygen cause?
Cells are unable to make energy
What does the respiratory system use to maintain normal (homeostasis) blood gas?
Negative feedback loop
How do chemoreceptors work?
Sense changes in chemical composition
What are the 3 stages of the respiratory systems negative feedback loop?
Integrator- brainstem (medulla oblongata & pons)
Effectors- changes to respiratory rate & depth
What two types of chemoreceptors are there?
Central & peripheral
What do central chemoreceptors send signals to?
What do central chemoreceptors respond to?
Changes in blood pH levels & levels of CO2 in arterial blood (PaCO2)
What are central chemoreceptors not sensitive to?
What are peripheral chemoreceptors also called?
Where are peripheral chemoreceptors located?
Close to the carotid arteries & receive a rich blood supply
What do peripheral chemoreceptors respond to?
Changes in blood pH, PaCO2 & significant changes in PaO2 (arterial oxygen level)
What provides information about lung inflation?
Lung stretch receptors
What gives input regarding respiratory volume control?
Cerebral cortex (limited by the need to regulate blood gas levels)
What do irritant receptors do?
Trigger protective reflexes (cough, sneeze, etc.)
What are the two laws regarding gas?
1. Air moves from higher to lower pressure.
2. The pressure exerted by air is inversely related to its volume.
What muscles are used during inspiration & how do they work?
External intercostal muscles
Muscles contract to expand chest.
What happens to the lungs during expiration?
Elastic recoil of lungs
What does forced expiration require?
Contraction of internal intercostal muscles.
Accessory muscles may be recruited in very heavy breathing/respiratory illness.
What is tidal volume?
How much air you breath in & out.
What is vital capacity?
Maximum inspiration followed by maximum expiration.
What is residual volume?
Air that remains in the lungs after maximum expiration.
What does PEFR stand for?
Peak Expiratory Flow Rate
What does peak flow measure?
Width of airways. Measures speed in ltrs per min.
What does FEV1 stand for?
Forced expiratory volume in 1 sec
What does FEV1 measure?
Provides info on airway resistance & efficiency of respiratory muscles.