Respiratory Anatomy

Question 1

What is the name for the process for breathing?

Answer 1

Cyclical respiratory muscle contraction

Question 2

What are turbinates?

Answer 2

Found behind the nose
Membrane structure which provides large surface area for heating and humidifying the air
Disrupts air flow, creating resistance to increase the chance of inhaled particles being trapped

Question 3

Why does air need to be humidified before entering the lungs?

Answer 3

To prevent the alveolar linings from drying out
O2 and CO2 can’t diffuse through dry membranes

Question 4

What are the lobe layout in the lungs and why is this?

Answer 4

3 lobes on right
2 lobes on left
Asymmetrical as need space for heart on left

Question 5

What is the respiratory quotient and how do you calculate it?

Answer 5

Ratio of CO2 produced to O2 consumed
CO2/O2

Question 6

Name and describe the two autonomic receptors for respiratory:

Answer 6

Muscarinic- Ach- constriction M3 muscarinic receptor, innervate mucous glands (parasympathetic)
Adrenergic- epinephrine- dilation- B2 receptor (sympathetic)

Question 7

What are NANC nerves and how can they work in changing diameter of blood vessels?

Answer 7

Non Adrenergic Non Cholinegeric nerves
Inhibitory- efferent fibres causing bronchodilation
Excitatory- sensory fibres leading to bronchoconstriction, relax airway smooth muscle by releasing nitric oxide and vasoactive intestinal peptide.

Question 8

What is asthma?

Answer 8

Recurrent attacks of breathlessness
The airway obstruction is mostly reversible with treatment

Question 9

What is COPD?

Answer 9

Airflow obstruction which is usually progressive, not fully reversible
From the result of chronic inflammation

Question 10

What are the causes of asthma?

Answer 10

Genetic: age, atopy, gender
Environmental: Allergens, pollutants, smoke

Question 11

What is extrinsic and intrinsic asthma?

Answer 11

Extrinsic- atopic, episodic, younger early onset, raised IgE levels (allergic)
Intrinsic- non- atopic, chronic, late adult onset, exercise, normal IgE levels (non-allergic)

Question 12

What are the causes of COPD?

Answer 12

More than 90% due to smoking but only 10% of smokers have it
2% genetic, anti-alpha trypsin deficiency

Question 13

What are exacerbations?

Answer 13

A sustained worsening of the patients symptoms from their usual

Question 14

What is diurnal variation?

Answer 14

From day to day, symptoms are different

Question 15

What is the larynx compromised of?

Answer 15

Thyroid cartilage

Question 16

Which cells produce mucus?

Answer 16

Goblet and submucosal cells

Question 17

What is the trachea compromised of?

Answer 17

Incomplete rings made of hyaline cartilage

Question 18

What are the three neural control components in respiration?

Answer 18

1. Generation of alternating inspiration/ expiration rhythm
2. Regulation of magnitude of ventilation
3. Modified respiratory movements
   e.g voluntary= speech, involuntary= cough/sneeze

Question 19

Describe the respiratory tree from top to bottom:

Answer 19

Nasal passages
Mouth
Pharynx
Larynx
Trachea
Bronchi
Bronchioles

Question 20

Name the 3 key anatomies in the body for breathing:

Answer 20

Diaphragm
External intercostal muscles
Thorax

Question 21

Describe inspiration:

Answer 21

The diaphragm contracts and pulls out The intercoastal muscles contract
Pulls rib cage up and out
thoracic cavity expands, active process

Question 22

Describe expiration:

Answer 22

When nerves stop firing, the diaphragm relaxes, the external intercostal muscles relax and thoracic cavity reduces passive process

Question 23

Where in the brain is breathing controlled?

Answer 23

Medulla oblongata

Question 24

In which complex is the respiratory rhythm generated?

Answer 24

Pre- Botzinger complex

Question 25

Which nerves initiate inspiration?

Answer 25

Bursts of action potentials in spinal motor nerves The phrenic nerve innervates diaphragm The intercostal nerves innervate external intercostal muscles

Question 26

Describe the process how lungs don't over inflate:

Answer 26

Lungs have pulmonary stretch receptors the Hering-Breur reflex is activated When the lungs inflate, the negative feedback causes the inspiratory centre to stop firing to phrenic nerve so diaphragm doesn't contract and activate the stretch receptor in the lung

Question 27

What is the equation to work out flow of air?

Answer 27

Flow= (P alvelor- P atmostphere)/ Resistance

Question 28

What is hyperventilation?

Answer 28

An increase in ventilation so a decrease in CO2

Question 29

What is Boyles law and how does this relate to breathing?

Answer 29

P1V1=P2V2 Compression of lungs so if volume decreases, pressure increases so air moves out

Question 30

How does Fick's law relate to efficient alveolar structure for efficient gas exchange?

Answer 30

The shorter the distance and the greater the surface area through which diffusion takes place, the greater the rate of diffusion

Question 31

Describe the structure and components of the alveoli:

Answer 31

Single layer of flattened type 1 alveolar cells 5% made of type 2 alveolar cells, which produce pulmonary surfactant Pores of Khon in the walls between adjacent alveoli to permit airflow between these

Question 32

What is transpulmonary pressure (Ptp)?

Answer 32

It is a difference in pressure between the inside and outside of the lungs

Question 33

What is intrapleural pressure? (Ppip)

Answer 33

As the thorax expands volume increases The intrapleural pressure decreases and lungs expand The pressure across the wall of lung increases

Question 34

How do you calculate transpulmonary pressure?

Answer 34

Alveolar pressure- Intrapleural pressure

Question 35

What is lung compliance?

Answer 35

The magnitude of change in volume

Question 36

What does lung compliance depend on?

Answer 36

The surface tension of water in alveoli- type 2 alveolar cells secrete pulmonary surfactant in alveoli which helps prevent collapse The stretchability- how easily they open and close from the connective tissue (elastin)

Question 37

What occurs in the pulmonary capillaries?

Answer 37

O2 from the atmosphere enter the alveoli which binds to haemoglobin and carried to the tissues CO2 which was dissolved into the blood by bicarbonate ions made back into CO2 to be released

Question 38

Why does oxygen need haemoglobin?

Answer 38

Oxygen has a low solubility in blood

Question 39

How does haemoglobin work?

Answer 39

Each haemoglobin can hold four oxygen molecules Works by association, once one oxygen is bound the other O2 can combine more freely and vice versa

Question 40

What occurs in the systemic capillaries?

Answer 40

HbO2 dissociate back into haemoglobin and O2 and leaves red blood cells Hb combines of H+ ions to form HHb Most CO2 is converted into HCO3- which is in the plasma

Question 41

Which two chemoreceptors control the magnitude and rate of ventilation?

Answer 41

Peripheral and central

Question 42

How do peripheral chemoreceptors work?

Answer 42

Found in carotid and aortic bodies Rich in O2- respond to changes in blood pH (H+) and gas content

Question 43

How do central chemoreceptors work?

Answer 43

Very sensitive, stimulated by an increase in H+ ions in brains extracellular fluid An increase can both cause increasing contraction and ventilation

Question 44

What is cyanosis?

Answer 44

Blueness of skin resulting from insufficiently oxygenated blood in arteries

Question 45

What is hypercapnia?

Answer 45

Excess CO2 in arterial blood

Question 46

What is hypocapnia?

Answer 46

Lower than normal CO2 in arterial blood

Question 47

What is hypoxia?

Answer 47

Insufficient O2 at cellular level

Question 48

What is apnea?

Answer 48

Where your breathing stops due to the airways becoming too relaxed and narrow when sleeping