Lecture 13 & 14 - The Respiration system

Question 0

What is atmospheric pressure at sea level?

Answer 0

101kPa or 760mm Hg

Question 1

What is the composition of dry atmospheric air?

Answer 1

78% nitrogen
21% oxygen
0.04% carbon dioxide

Question 2

What is the partial pressure of Oxygen in the atmosphere at sea level?

Answer 2

21.2kPa or 160mm Hg

Question 3

What is the average lung capacity of an adult male?

Answer 3

4/6 litres

Question 4

What is tidal breathing?

Answer 4

Normal resting breathing

Question 5

What is the resting ventilation rate?

Answer 5

15 breaths per minute

Question 6

What is the tidal volume?

Answer 6

The volume of air that is inhaled/exhaled in a single such breath which is about 0.5 litres

Question 7

What is the forced vital capacity?

Answer 7

The total volume of air that can be breathed out of the lungs with maximum effort in one breath

Question 8

What is the forced expiratory volume?

Answer 8

A measure of how much of this air is breathed out in the first second

Question 9

What figures can be expected with an obstructive deficit?

Answer 9

FEV1 < 80% predicted
FVC can be reduced
FEV1/FVC ration < 0.7

Question 10

What diseases can cause an obstructive deficit?

Answer 10

Asthma
Chronic obstructive pulmonary disease (COPD)
Chronic bronchitis
Emphysema

Question 11

What figures can be expected with a restrictive deficit?

Answer 11

FEV1 < 80% predicted
FVC < 80% predicted
FEV1/FVC is >0.8

Question 12

What diseases can cause a restrictive deficit?

Answer 12

Cystic fibrosis
Tumours
Weak respiratory muscles
Pneumothorax

Question 13

What are the six function of external respiration?

Answer 13

Ventilation of the lungs
Gaseous exchange at lung/capillary interface
Carriage of oxygen to the metabolising tussues
Gaseous exchange at tissue/capillary interface
Carriage of carbon dioxide from the metabolising tissues

Question 14

What organs make up the respiratory system?

Answer 14

Nose
Pharynx
Larynx
Trachea
Bronchi
Lunge

Question 15

What are the two main functions of the respiratory system?

Answer 15

Brings oxygen into our bodies

Gets rid of carbon dioxide

Question 16

What do the pulmonary arteries do?

Answer 16

They carry deoxygenated blood from the right atrium of the heart to the lung

Question 17

What does the pulmonary vein do?

Answer 17

Carries oxygenated blood from the lungs to the left atrium to the heart

Question 18

What is the pleural cavity?

Answer 18

The space between the two pleural layers, it normally contains a small amount of pleural fluid

Question 19

Where are the pacemakers of pulmonary ventilation?

Answer 19

The medulla oblongata of the brain stem

Question 20

What happens during inhalation?

Answer 20

The diaphragm contracts and moves down, causing the chest to expand decreasing the pressure in the lungs causing air to come rushing in

Question 21

What happens during expiration..

Answer 21

The diaphragm relaxes and moves up causing the chest to contract increasing the pressure in the lungs causing air to be forced out

Question 22

What is airway resistance dependent on?

Answer 22

Radius of airways
Length of airways
Number of airways

Question 23

What is compliance?

Answer 23

The ability of the lung to stretch

Question 24

What is surface tension in the lungs?

Answer 24

The pressure exerted upon the alveoli

Question 25

How much oxygen is dissolved in plasma?

Answer 25

1.5%

Question 26

How much oxygen is binded to haemoglobin?

Answer 26

98.5%

Question 27

What is arterial pO2?

Answer 27

100mm Hg

Question 28

What is venous pO2 at rest?

Answer 28

45mm Hg

Question 29

What is venous pO2 at exercise?

Answer 29

25mm Hg

Question 30

What increases the affinity of haemoglobin?

Answer 30

Increase in pH Decrease in pCO2 Decrease in temp

Question 31

What causes a decrease in haemoglobins affinity for oxygen?

Answer 31

Decrease in pH Increase in pCO2 Increase in temperature

Question 32

What is the Bohr Effect?

Answer 32

An adaptation i animals to release oxygen in the oxygen stwrved tissue as the high pCO2 causes low pH, lowering the haemoglobins affinity for oxygen causing it to release the oxygen.

Question 33

How much carbon dioxide is dissolved in plasma?

Answer 33

8%

Question 34

How much carbon dioxide is bound to carbamino compounds?

Answer 34

12%

Question 35

How much carbon dioxide is carried as bicarbonate?

Answer 35

80%

Question 36

What controls inspiration?

Answer 36

The phrenic nerve which is the major nerve supply to the diaphragm

Question 37

What are the two types of chemoreceptors?

Answer 37

Peripheral | Central

Question 38

What are the peripheral chemoreceptors in the respiration system?

Answer 38

The aorta and carotid arteries which responde to hypoxia and hypercapnia

Question 39

What is the central chemoreceptor in the respiratory system?

Answer 39

The medulla which responds to a decrease in pH in the cerebrospinal fluid and an increase in pCO2