Ch7 Exchange surf. + breathing

Question 1

How does gas exchange and transport compare in single celled organisms and multicellular organisms?

Answer 1

Question 2

What are features of a specialised exchange surface?

Answer 2

Question 3

Explain the process and components of the gas exchange system in bony fish:

Answer 3

Question 4

How are gills adapted to be efficient ?

Answer 4

Question 5

How are fish gill filaments adapted to optimise gas exchange?

Answer 5

• gill filaments have folds (secondary) lamellae that contain network of capillaries
• Blood flows through blood capillaries in opposite direction to flow of water
• = larger SA

Question 6

What is Counter-current flow and why is it important (fish only)

Answer 6

• fresh water flows over gills in 1 direction
• counter-current flow is….:
• water + blood in gills flow in opposite directions.
• maintains favourable concn gradient for diffusion of both gases.

Question 7

Describe the insect tracheal system:

Answer 7

Question 8

How are tracheoles adapted to supply insects with sufficient gas exchange?

Answer 8

Question 9

How can you increase the rate of airflow in an insect’s tracheal system for a more active insect?

Answer 9

Question 10

Describe the Nasal Cavity:

Answer 10

Question 11

Describe the Trachea:

Answer 11

Question 12

Describe the Bronchus:

Answer 12

Question 13

Describe the Bronchioles:

Answer 13

Question 14

Describe the Alveoli:

Answer 14

Question 15

How are the alveoli adapted to optimise gas exchange in multicellular organisms?

Answer 15

Question 16

Explain the mechanism of inspiration and expiration:

Answer 16

Question 17

What is the role of lung surfactant in a new born baby?

Answer 17

• Lung surfactants contain phospholipids (hydrophilic and hydrophobic)
  
  • Surfactant stops the alveoli collapsing and sticking together as baby exhales.

Question 18

What does a peak flow meter do?

Answer 18

Peak flow meter measures rate at which air is expelled.

Often used by asthama.

Question 19

What does a vitalograph show?

Answer 19

Vitalograph are more advanced versions of peak flow meters.

They produce a graph showing volume + rate of exhaled air - called the Forced Expiratory Volume.

Question 20

What does a Spirometer show and what precautions should one take before using one?

Answer 20

Spirometers used to investigate breathing patterns or different components of lung volume.

Before each use check:

• Has fresh air
• Mouth piece disinfected
• Equipment is working properly e.g. water level, valve.
• Tanks contains NaOH, KOH or Ca(OH)2 to absorb CO2
• Air chamber rises during expiration.

Question 21

Define Total Lung Capacity (TLC):

Answer 21

TLC is the total volume of lungs : sum of vital capacity + residual volume.

Question 22

What is the Vital Capacity?

Answer 22

Maximum Volume of air that can be inhaled / exhaled in one breath.

Question 23

What is the Residual Volume?

Answer 23

Volume of air left in lungs after maximum exhalation - it cannot be measured directly.

Question 24

What is Tidal Volume?

Answer 24

Volume of air moving in + out of lungs with each resting breath

Approx. 500cm3 in most adults (15% of Vital Capacity)

Question 25

What is the Inspiratory reserve volume (IRV)?

Answer 25

IRV = maximum volume of air you can breathe in over + above normal inhalation.

Question 26

What is Expiratory Reserve Volume (ERV)?

Answer 26

ERV = maximum volume of air you can exhale over + above normal Tidal Volume you breathed out.

Question 27

How to calculate Ventilation Rate?

Answer 27

Ventilation Rate = tidal volume x 500 breathing rate. (cm3)