Respiratory

Question 1

Describe the definitions

Answer 1

Tidal volume - normal air displaced between inspiration and expiration

Functional residual volume - Air present at the end of passive expiration

residual volume - volume of air in lungs after most forcible expiration

Vital capacity - After maximum inhalation the maximum volume of air that can be expelled following a forcful expiration

Question 2

describe the Lobation of the lung

Answer 2

Question 3

What are the two types of pleura ?

Answer 3

1. Visceral pleura - attached to surface of lung, including fissures
2. Parietal pleura - Derived from somatic mesoderm.

• Costal pleura - Inside the wall of the rib cage
• Mediastinum pleura - inside lateral wall of rib cage (mediastinum contents - heart and all vessels, oesphagus,trachea, phrenic nerves, thymus & lymph nodes)
• Diaphragmatic pleura - lines cranial surface of diaphragm
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Question 4

Name the components of the conducting airways and respiratory zone

Answer 4

Conducting airways:

• trachea
• bronchi
• bronchioles
• terminal bronchioles

Respiratory zone:

• Respiratory bronchioles
• aveolar ducts
• aveolar sacs

Question 5

What are clara cells

Answer 5

Cells of the bronchiolar epithelium which secrete surfactant. Not the same as type ll aveolar, they have anti inflammatory function

Question 6

Describe specialisation of alveolar structure

Answer 6

• Shared septum - protects agains alveolar collapse
• Pores of khons - Gaps in alveolar septa which allow more efficient movement of inspired air. Also prevent lung from collapsing by equalizing pressure in adjacent alveolar

Question 7

Whats the definition of compliance?

Answer 7

Change in volume/Change in pressure

Question 8

What occurs during inspiration and expiration?

Answer 8

Inspiration :

• Phrenic nerve innervates diaphragm to flatten and enlarge thoracic cavity
• Ribs move outwards. Parietal pleura then move out, causing visceral pleura and the lungs outwards
• Pressure lowered

Expiration:

• Passive process
• Diaphragm relaxes, reducing thoracic volume
• Pressure increased and lung recoils expelling air
• Internal intercostals can help reduce thoracic volume

Question 9

What resiratory problem are race horse prone to ?

Answer 9

Excercise induce pulmonary haemorrhage (EIPH)

Blood vessels burst under high pressure

Question 10

What affect does a change in PH have on haemoglobin affinity?

Answer 10

1. Decrease in PH (more acidic) leads to a decrease in affinity for oxygen. Therefore oxygen more readily deposited to tissues
2. Increase in PH (alkaline) leads to increase in oxygen affinity. Therefore oxygen is less readily released by haemoglobin