BREATHING AND EXCHANGE OF GASES
1. ………. are the structural and
functional units of lungs. (Score 1)
Answer: Alveoli
2. Lungs are covered by double-layered ……….
(Score 1)
Answer: Pleura
3. Note the relationship between the first
pair and fill up the blank. (Score 1)
TV: 500 ml
RV:
……….
Answer: 1100
– 1200 ml
4. Expand
and distinguish between the following abbreviations: (Score 2)
a. TV b. RV
Answer:
a. Tidal
Volume: Volume of air inspired or
expired during normal respiration.
b.
Residual
volume: Volume of air remaining in
the lungs after a forcible expiration.
5. Analyze the concept map
given below and if have a mistake, reconstruct it. (Score 2)
Answer:
6.
Differentiate inspiration and expiration. (Score 2)
|
Inspiration |
Expiration |
|
…………………… …………………… |
…………………… …………………… |
Answer:
|
Inspiration |
Expiration |
|
· Active intake of air into lungs. · Diaphragm and external intercostal muscles contract. |
· Passive expelling of air from the lungs. · Diaphragm and external intercostal muscles relax. |
7. a) Identify the graph
given below. (Score 3)
b) Find out the PO2 at which
90% saturation of haemoglobin with oxygen occurs.
c) List the factors responsible for the
formation and dissociation of oxyhaemoglobin.
Answer:
a) Oxygen-Hb
dissociation curve.
b) 60 mm Hg
c) pO2, pCO2, H+ concentration, Temperature.
8. Asthma and emphysema are two disorders of the human respiratory system. Mention their causes and symptoms. (Score 2)
Answer:
Asthma: Difficulty in breathing causing
wheezing due to inflammation of bronchi and bronchioles.
Emphysema: Damage of alveolar walls. Major cause
is cigarette smoking.