The Respiratory System Flashcards Preview

1.1.1. Body Logistics > The Respiratory System > Flashcards

Flashcards in The Respiratory System Deck (37)
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1
Q

How much pulmonary vasculature makes up the lungs weight?

A

Pulmonary vasculature = 500ml blood = 40% lung weight

2
Q

Describe what happens during inhalation?

A

Diaphragm contracts = moves down, increasing volume of thoracic cavity = pressure inside decreases, air moves from an area of higher pressure, the atmosphere, to an area of lower pressure, the lungs

3
Q

What happens during exhalation?

A

diaphragm relaxes, moves up = reduces volume of thoracic cavity = intrapulmonary pressure increases = Air flows out of Lungs to lower atmospheric pressure

4
Q

Where is odour detected?

A

Olfactory region –> thick pseudostratified columnar epithelium, dendrite + non-motile cilia detect odour – no goblet cells

5
Q

What are the secretion in the trachea and bronchi?

A

mucins, water, serum proteins, lysozyme (destroys bacteria), antiproteases (inactivate bacterial enzymes)

6
Q

Describe the nasal non-olfactory region

A

Non-olfactory region –> pseudostratified ciliated epithelium, mucous glands, venous plexus swells alternating nostril airflow

7
Q

Outline the structures in the larynx

A

Larynx = true vocal cord – open close many times, ventricles contribute to resonance of voice. Vocal cord (help stop foreign objects) = vocal ligament + vocalis muscle

8
Q

Describe the trachea

A

ridged, C shaped rings to keep it open – transform to bone with ageing. Submucosa thicker in COPD = small lumen

9
Q

What is structurally different between the trachea and bronchi?

A

trachea = C shaped rings, bronchi = rings completely encircle lumen

10
Q

When is the respiratory system intrapulmonary?

A

secondary bronchi

11
Q

Describe the bronchioles

A

Bronchioles = blood supply pulmonary arteries (deoxygenated) pulmonary vein (oxygenated) – NO CARTILAGE (allows constriction = bronchoconstriction), contracts in asthma. Clara cells = secrete surfactant lipoprotein stop walls sticking together.

12
Q

Name the smallest airway and its key feature

A

Terminal bronchioles = smallest airway, no goblet cells – stop drowning in mucus

13
Q

Where are the mucous membranes present

A

Conducting zone = MUCOUS MEMBRANE

14
Q

The pleural sacs are what type of membrane

A

Serous membrane

15
Q

What is the respiratory zone?

A

Respiratory zone = gas exchange – abundant capillaries – respiratory bronc. bronchioles, alveolar ducts, alveolar sacs, alveoli

16
Q

Describe the alveoli and the cells types present

A

90% cover by type I pneumocytes (squamous), 10% type II pneumocytes (cuboidal) secrete surfactant, devel until 8yrs, 300 million, surrounded by basketwork of elastin/capillaries/reticular fibres, air as close as 0.2μm from blood

17
Q

How does hyperventilating lead to fainting?

A

Drop in CO2 due to hyperventilating = hypocapnia – low CO2 = less carbonic acid = blood pH rises (low pH = changes shape Hb, high pH = vasoconstriction) not enough blood to the brain = faint

18
Q

Why does oxygen dissociate from haemoglobin?

A

Active tissue burns through oxygen – low partial pressure = oxyhaemoglobin loses oxygen from plasma to tissue. Other triggers = heat (changes Hb shape), CO2 (binds Hb, changing shape + makes blood more acidic H+ bind) – activate the release of oxygen = lower Hb affinity for oxygen

19
Q

What is the Haldane effect?

A

Deoxygenated blood can carry increasing amounts of CO2, whereas oxygenated blood has a reduced CO2 capacity.

20
Q

What is the Bohr Effect?

A

haemoglobin’s oxygen binding affinity is inversely related both to acidity and conc of CO2

21
Q

How can someone get a hoarse voice?

A

Hoarse voice = impinging on left recurrent laryngeal nerve – loops under aorta (can be caused by aortic aneurism)

22
Q

In regards to respiratory anatomy how can wasting in the lower arm be caused?

A

Muscle wasting lower arm = cancer in lung apex impinges brachial plexus

23
Q

What causes paralysis on one side of the diaphragm?

A

tumour impinges left/right phrenic nerve = ipsilateral elevation

24
Q

Describe COPD

A

Caused by smoking or alpha 1-antitrypsin def: Goblet cell hyperplasia, smaller proportion of ciliated cells, hypertrophy of submucous glands = more mucus and fewer cilia to move mucus

25
Q

Outline emphysema

A

Destruction of alveolar walls and permanent enlargement of air spaces which can result from smoking or alpha 1-antitrypsin deficiency. Alveolar walls normally hold bronchioles open. Damage = collapse = difficult for lungs to empty = air trapped in alveoli. Pursed lip breathing. Damage = loss of elastin = chest springs out = barrel chest

26
Q

What is pneumonia?

A

Inflammation of the lung caused by bacteria, lung consolidates (filled with liquid) as the alveoli fill with inflammatory cells. Streptococcus pneumoniae

27
Q

Name the 2 pleura and where they are found

A

Parietal pleura –> lines the chest wall. Visceral pleura –> cover lung

28
Q

How does surface tension work?

A

Water molecule, +ve and –ve ends attract each other – H bonds. At surface - water molecules don’t have any charges pulling on them from above = able to get more densely packed = stronger intramolecular force = surface tension

29
Q

What is the pleural fluid?

A

separates and lubricates 2 membranes, provides surface tension to prevent the lung from collapsing. -ve pressure keeps pleurae together = lung expands

30
Q

What are the pleural fluids –ve pressures?

A

Inspiration = -8cmH2O (below atmosphere) Exhalation -4cmH2O (below atmosphere)

31
Q

What is boyles law?

A

When the volume of a container increases, the pressure decreases. When the volume of a container decreases, the pressure increases

32
Q

Outline LaPlaces Law

A

If two areas of different pressure communicate, gas will move from area of higher pressure to area of lower pressure

33
Q

What can the pleural space be incorrectly filled with?

A

Air –> pneumothorax. Blood –> haemothorax. Pus –> empyema. Watery transudate or exudate –> pleural effusion

34
Q

What is the role of surfactant?

A

surface tension wants to collapse the alveoli, surfactant hydrophilic heads interfere with H bond = decreases surface tension = less chance of alveoli collapse

35
Q

List the order of the respiratory system

A

Nasal cavity, pharynx, larynx, trachea, primary right/left bronchi, secondary bronchi, bronchioles, terminal bronchioles, respiratory bronchioles, alveolar ducts, alveolar sacs, alveoli.

36
Q

What are Clara cells?

A

Found in bronchioles, secrete surfactant lipoprotein stop walls sticking together, CC16 lower = lung damage, higher = leaking across air-blood barrier

37
Q

What is alpha 1-antitrypsin?

A

It protects tissues from enzymes of inflammatory cells especially neutrophil elastase. In its absence (such as in alpha 1-antitrypsin deficiency), neutrophil elastase is free to break down elastin, which contributes to elasticity of lungs = emphysema or COPD