Week 3

Question 1

Upper tracts of respiratory system

Answer 1

Nose and nasal cavity
Pharynx
Larynx

Question 2

Lower tracts of respiratory system

Answer 2

Trachea
Bronchial tubes
Alveoli

Question 3

4 layers of trachea

Answer 3

Mucosa
Sub mucosa
Hyaline cartilage
Adventitia

Question 4

Epithelium of primary secondary and tertiary bronchial tubes

Answer 4

Pseudostratified ciliated columnar epithelium with goblet

Question 5

Epithelium of large bronchioles

Answer 5

Simple ciliated with some goblet

Question 6

Small bronchioles

Answer 6

Simple ciliated with few goblet cells

Question 7

Terminal bronchioles epithelium

Answer 7

Simple cuboidal

Question 8

Structure of alveoli

Answer 8

Simple squamous epithelium (type I cells)
Alveolar wall and capillary wall form respiratory membrane (gases must diffuse across this)

Question 9

Main premise of boyle’s law

Answer 9

If the volume of a gas is increased, its pressure decreases (and vice versa)

Question 10

Mechanics of inflating lungs

Answer 10

To inflate lungs with external air, we must increase lung volume (boyle’s law) to reduce intrapulmonary/alveolar pressure.

Question 11

Mechanics of exhalation

Answer 11

We must increase alveolar pressure by reducing lung volume. Once air pressure is lower than alveolar pressure, air is expelled from lungs

Question 12

Structures that allow pulmonary ventilation

Answer 12

Rib cage
Diaphragm
External intercostals
Internal intercostals
Abdominals, obliques, scalenes, SCM

Question 13

Muscles of Inhalation

Answer 13

Diaphragm
External Intercostals

Question 14

Three different air pressures involved in breathing

Answer 14

Atmospheric
Alveolar
Intrapleural

Question 15

Factors that effect pulmonary ventilation

Answer 15

Alveolar surface tension (pulls alveoli slightly inwards so must be overcome to expand their volume)
Lung Compliance( describes the ease of lung expansion - caused by the difference between intrapleural and alveolar pressure)
Airway Resistance (Resistance caused by walls of bronchial tubes- asthma and chronic bronchitis cause this)

Question 16

4 categories of total lung volume

Answer 16

Residual volume
Tidal volume
Inspiratory reserve volume
Expiratory reserve volume

Question 17

Residual Volume

Answer 17

Not all air expelled from lungs
Volume of air remaining in lungs after forced expiration

Question 18

Tidal volume

Answer 18

Resting volume of air inhaled and exhaled
Represents air moved in one breath

Question 19

Inspiratory Reserve Volume

Answer 19

Achieved during deep inhalation
Excess volume inhaled beyond normal tidal volumes

Question 20

Expiratory reserve volume

Answer 20

Achieved during deep exhalation
Excess volume exhaled beyond normal tidal volume

Question 21

Inspiratory Capacity

Answer 21

Inspiratory reserve volume + tidal
Maximum volume of air inhaled from normal

Question 22

Functional Residual Capacity

Answer 22

Expiratory reserve volume + residual volume
Volume of air remaining in lungs after normal expiration

Question 23

Vital Capacity

Answer 23

Inspiratory reserve volume + tidal volume + expiratory reserve volume
Maximum volume of air that can be inhaled/exhaled

Question 24

Total lung capacity

Answer 24

Vital capacity+ residual volume

Question 25

Partial Pressure

Answer 25

In a mixture of gases such as our atmospheric air, we can calculate the individual contribution to the total air pressure by a single gas.
Total air pressure is the sum of the partial pressures of all gases in a mixture

Question 26

Partial Pressure in the Respiratory System

Answer 26

Partial pressure of oxygen must be higher in the alveoli compared to blood in the pulmonary capillaries (ensures oxygen diffuses into blood). Partial pressure of Co2 must be higher in the pulmonary capillary blood compared to alveoli.

Question 27

Gas solubility

Answer 27

When a gas is in contact with a liquid, the dissolved gas is proportional to its partial pressure and solubility (Henry’s Law). A high PP and solubility will increase the amount of gas dissolved in solution.

Question 28

Factors affecting oxyhaemoglobin saturation

Answer 28

Acidity
Carbon dioxide partial pressure
Temperature

Question 29

Carbon dioxide methods of transportation

Answer 29

Bicarbonate ions (70%)
Carbamino compounds (23%)
Dissolved Co2- compounds (7%)

Question 30

Where is PO2 highest in external respiration

Answer 30

Alveolar Air

Question 31

Where is PCO2 highest in internal respiration

Answer 31

Tissue cell (45mmHg)

Question 32

Vasoconstriction

Answer 32

Sympathetic nervous system activation
Epinephrine and norepinephrine
Hypertension

Question 33

Vasodilation

Answer 33

Prostaglandins and histamines
ACE inhibitors

Question 34

Sympathetic nervous system activation

Answer 34

the activation of the sympathetic nervous system enhances the respiratory system’s ability to meet increased demands for oxygen during stress or physical activity. It achieves this through mechanisms such as bronchodilation, increased respiratory rate, reduced mucous secretion, and improved airway patency.

Question 35

Parasympathetic nervous system activation

Answer 35

parasympathetic nervous system activation generally results in bronchoconstriction, decreased respiratory rate, increased mucous secretion, and increased airway tone. These effects are aligned with the body’s needs during rest and relaxation, helping to maintain normal respiratory function and protect the airways.