B1- Lungs

Question 1

What is boyles law

Answer 1

Inverse relationship between volume eg of thorax and rhe pressure

Question 2

What two types of resp are there

Answer 2

Cellular generating atp (internal)

External is breathing

Question 3

Why is air humidified in upper resp tract

Answer 3

So exchnage tissues dont dry out

and so gas transfers freely into blood in alveoli

Question 4

What is rhe diameter and csa of trachea

Answer 4

20 mm diamter and small csa of 2.5cm = airflow resistance

Question 5

Alveoli are what diameter and sa

Answer 5

0.3mm

Large sa of 1 x 10^6 (tennis court)

Question 6

Which area of airway is first line of defence eg by cilia and ifn

Answer 6

Ciliated epihtelial pseudostratified columnar (eg nasal)

Question 7

Where is contona ideal colonisation

Answer 7

In nasal epi cells or govlet secretort cells

Question 8

Which article disxusses sars cov 2 effects on airway epi cells

Answer 8

Zhu et al 2020

Question 9

What sorts of effects do they have in the cells

Answer 9

Destroy cilia by staying at apical surfaces

Form gisnt syncytial cells (fusion of cells)

Destroy tight cell junctions

Question 10

Which article discusses ifn in naaal epi cells /sexretory and covid

Answer 10

Hatton et al 2020

Question 11

Is ifn blocked by covid in nasal and sexreotry

Answer 11

No iust delayed

Question 12

How

Answer 12

Downrefulation of Isg (ifn stimulating genes)

Question 13

Which mutstion seen in severe xovid patients

Answer 13

Ifn receptor which sigansl vis jak stat for antigirql wffects

Question 14

What is point of ifn 1 and 3

Answer 14

Epithelial integrity and refcued viral replication and t regs too

Question 15

What do capillaries on alveoli allow for ventilation

Answer 15

Ventilstion perfusion matching (v/q)

Question 16

What % do capillaries cover alveoli surface

Answer 16

80-90%

Question 17

How does alveoli connextive tissue of lungs allowing recoil and expanding

Answer 17

Elastin and collagen

Question 18

What is condition callrd shich causes consfant dilstion of sireays whcih forms mucus build up and infection

Answer 18

Bronchiecstasis

Question 19

What is it caused by

Answer 19

Inflammatory damage eg to elastic and muscular components of bronchi

Question 20

Which article discusses alveolar cells

Answer 20

Guillot 2013

Question 21

What types of cells are type 2

Answer 21

Large cuboidal cells

Question 22

What growth factor allows conversion of orsophagual to respiratory epitheliumeg after infection

Answer 22

Fgf

Question 23

What are bacs cells which are upregulated after ciral infection

Answer 23

Bronchioalveolar cells near ducts which differentiate to rype 1 and type 2 cells

Question 24

Which alveolar cells are self renewable and form the other

Answer 24

Type 2

Question 25

What causes surface tension of alveoli

Answer 25

Air blood barrier (reduced to 1micronetre by flat type 1)

Question 26

How is surfsctant responsible in precenting collapse

Answer 26

Reduce surface tension

Question 27

Which right junctions are a barruwr to infection in alveolar cells to block interstitial

Answer 27

Claudin 3

Question 28

Which alveolar cells have tlr and contsct macrophages for clearance of infection

Answer 28

Type 1

Question 29

During which infection

Answer 29

Pneumococcal pneumonia

Question 30

Ofher than opsonins whag are surfactant p a and d

Answer 30

They are antininflam by rleeasing tgf b and il10

Question 31

What allows thoracic cage and lung moving up together

Answer 31

Parietal pleura (costal which adheres thoracic wall)

Question 32

What allows passive exp

Answer 32

Recoil of elastic connrctive tissue

Question 33

In inspirstion what forms 70% of the volume change so pressure is lower than atmospheric

Answer 33

Dipahragm (moves 1-2cm)

Question 34

What are the other 30%

Answer 34

Accesory and intercostals

Question 35

What measures lung function

Answer 35

Spirometer

Question 36

What is fev1 which is reduced in smoking etc eg copd due to obstruction

Answer 36

Maximal vol of air expired in 1 second after maximal nspiratioj

Question 37

What is it depeendant on

Answer 37

Body tempersture and sateuation of rhe air

Question 38

What is fvc alsonreduced

Answer 38

Max amount of air breathed out with msximal force applied after maximal inspiration

Question 39

Give an example of ehat causes lower fvc

Answer 39

Pulmonary fibrosis which reduces elasticity due to scarring