Resp Lecture 2

Question 1

Why is wrong with the drawings in the book of an alveolus

Answer 1

the volume of the alveolar air space is greatly reduced, and the thickness of the squamous pneumocytes and the capillary endothelial cells is exaggerated.

Question 2

Cartilage supports the large airways during inspiration, but does not continue beyond

Answer 2

the smallest bronchi. Mucous glands stop there too.

Question 3

Thickness of the epithelium decreases as

Answer 3

airway diameter decreases.

Question 4

The epithelium of the conducting airways contains secretory cells. Goblet cells secrete

Answer 4

mucus in the large airways, Club cells release a serous (watery) secretion in bronchioles.

Question 5

Small airways have more smooth muscle (in spiral orientation) in relation to their size than
large

Answer 5

ones, but the muscle coat does not continue beyond the smallest bronchioles.

Question 6

Subdivisions of the lung

• Primary bronchi (2) are

Answer 6

right and left main stem bronchi supplying each lung.

Question 7

Secondary bronchi are

Answer 7

lobar bronchi supplying lobes (2 on the left, 3 on the right).

Question 8

Tertiary bronchi are segmental bronchi supplying

Answer 8

segments of the lung (8 on the left, 10 on the

right). Each segment has its own air and blood supply.

Question 9

Each segment has its own air and blood supply. Thus when a localised tumour occurs in
the lung, a surgeon who

Answer 9

knows the approximate boundaries can remove one or more segments
containing the tumour without excessive leakage of air or blood from neighbouring segments.

Question 10

The lung is divided into

Answer 10

ten bronchopulmonary segments, each segment being supplied by a segmental (= tertiary) bronchus

Question 11

Pleurae

• A smooth membrane (pleura) covers

Answer 11

each lung; and also lines the thoracic cavity in which

the lung sits. The two membranes (pleurae) are continuous at the root of the lung (hilum).

Question 12

Although the fluid allows sliding movement between the pleurae, it also prevents them
from being separated. When the thoracic wall
moves inwards

Answer 12

inwards or outwards, the lungs must
follow. Similarly when the diaphragm moves
upwards or downwards, the lungs must follow.

Question 13

Quiet breathing: • Movement of the ribcage is responsible for

Answer 13

about 25% of air movement into and out of the lungs.

Question 14

Inspiration is active. It requires contraction of the external intercostal muscles which run

Answer 14

obliquely between ribs.

Question 15

Expiration is

Answer 15

passive. The ribcage returns to its resting position without requiring muscular
action.

Question 16

Breathing during exercise:

Answer 16

Both sets of intercostal muscles are now active; externals for inspiration, internals for expiration.

Question 17

Ventilation: movement of the diaphragm floor and roof

Answer 17

The diaphragm is a dome-shaped platform which forms the loor of the thorax and the roof of the abdomen.

Question 18

Ventilation: movement of the diaphragm

Answer 18

Its central part is a thin sheet of connective tissue, (technically an aponeurosis) called the central tendon. The lateral margins are muscular. The muscle is fast-acting skeletal muscle, innervated by the phrenic nerve.

Question 19

Contraction of the diaphragmatic muscle
lattens the diaphragm, pulling its central
dome downwards. This

Answer 19

increases the volume

of the thorax and causes inspiration.

Question 20

Passive relaxation of the muscle allows the

diaphragm to lift back towards

Answer 20

the thorax,

reducing thoracic volume, (expiration).

Question 21

Movement of the diaphragm is responsible

for

Answer 21

75% of bulk low of air during quiet
breathing, a smaller proportion during
exercise.

Question 22

Club cells secretions =

Answer 22

Water H2O with anti microbial enzymes

Question 23

Asthma

Answer 23

Rapid bronchi constraint swollen tubs

Question 24

Asthma treatment

Answer 24

Puffer brondilater =relaxation of smooth

Salbutamol - Ventolin

Question 25

Why can respiratory bronchioles take part in respiratory

Answer 25

They have alveolus budding off the tubes

Question 26

What dose surfactant do

Answer 26

Lines lungs stops them from sticking and collapsing

Question 27

Prem babe

Answer 27

Born before 30 weeks
When they breath out the alveolar stick tougher and the babe has to use a lot of effort breathing to unstick them =lots of pressure to re inflate. Neonatal respiratory distress
Can be treated

Question 28

The diffusion barrier aka

Answer 28

The blood air barrier

Question 29

The basement membranes between the epi and endo are fused because

Answer 29

For minimum distance

Question 30

Fibrosis =

Answer 30

Increased ct =increased distance = hypoxia -low O2 in blood

Question 31

Some bronchus sit

Answer 31

Out side the lungs

Question 32

If the plural space fills with air -

Answer 32

No ventilation because pressers cannot change

Question 33

pneumothorax

Answer 33

Collapsed lung no connection of pleura