Bmsc 208 Final Review Updated Actual Questions And Correct Answers

BMSC 208 FINAL REVIEW UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Question:
1. Four primary functions of the respiratory system
Answer:
1. Exchange of gasses between the atmosphere and blood
2. Homeostatic regulation of body pH
3. Protection from inhaled pathogens and irritating substances
4. Vocalization

Question:
2. Principles that govern bulk flow through CV system
Answer:
- flow occurs from region of high pressure to low pressure
- muscular pump creates the pressure gradients
- resistance is primarily influenced by diameter of tubes through which air is flowing

Question:
3. Four step process of external respiration
Answer:
Exchange 1 - atmosphere to lung Exchange 2 - lungs to blood Exchange 3 - Transport of gases in
blood Exchange 4 - blood to cells

Question:
4. Upper respiratory structures
Answer:
- nasal cavity
- pharynx
- larynx

Question:
5. lower respiratory structures
Answer:
- trachea
- right and left bronchus
- right and left lungs

Question:
6. Muscles of expiration
Answer:
internal intercostals abdominal muscles

Question:
7. muscles of inspiration
Answer:
Sternocleidomastoids Scalene external intercostals diaphragm

,Question:
8. Visceral pleura
Answer:
layer of pleura connected to outside surface of lungs

Question:
9. Parietal pleura
Answer:
outer later of connected to inside surface of the thoracic cavity

Question:
10. Functions of pleura
Answer:
1. create moist slippery surface
2. holds lungs tight to thoracic wall

Question:
11. Role of upper airways and bronchi
Answer:
Conditioning air before it reaches alveoli
- warming air to body temperature
- adding water vapour
- filtering out foreign material

Question:
12. Model of saline secretion by epithelial cells
Answer:
1. NKCC brings Cl- into epithelial cell from ECF
2. Apical ion channels, including CFTR, allow Cl- to enter the lumen
3. Na+ goes from ECF to lumen by the paracellular pathway, drawn by the electrochemical gradient
4. NaCl movement from ECF to lumen creates a concentration gradient so water follows into the
lumen

Question:
13. Cystic Fibrosis
Answer:
caused by an autosomal recessive mutation in the gene providing cystic fibrosis transmembrane
conductance
- this causes reduced production of saline
- mucus cannot be cleared properly allowing bacteria to colonize in the airways leading to reoccurring
lung infections
- also effects pancreas
named due to formation of cysts and fibrosis on pancreas

Question:
14. Type I alveolar cell

,Answer:
95% of surface area
- for gas exchange

Question:
15. Type II alveolar cell
Answer:
synthesizes surfactant

Question:
16. Dalton's Law
Answer:
the total pressure exerted by a mixture of gases is the sum of the pressure exerted by each gas
- also dependent on humidity of the air
- the pressure exerted by one gas is known as its partial pressure

Question:
17. Tidal volume
Answer:
amount of air entering and exiting the lungs during quiet respiration

Question:
18. total pulmonary ventilation
Answer:
TV x ventilation rate (frequency of breaths)

Question:
19. Inspiratory reserve volume (IRV)
Answer:
additional air that could still be inspired after quiet inspiration

Question:
20. Expiratory reserve volume (ERV)
Answer:
volume of air that still remains within the lungs that can be expired

Question:
21. Residual volume (RV)
Answer:
even with maximal expiratory effort air always remains in lungs
- can't be measured by spirometer

Question:
22. Important functions of residual volume
Answer:
1. Prevents airway collapse; after a collapse it takes an unusually large pressure to re-inflate it
2. It allows continuous exchange of gases

, Question:
23. Total lung capacity
Answer:
the sum of all 4 volumes

Question:
24. Functional residual capacity
Answer:
capacity of air remaining in lungs after quiet expiration = the sum of IRV + ERV

Question:
25. Inspiratory capacity
Answer:
the sum of IRV and TV representing the maximal amount of air that one can inspire

Question:
26. Vital capacity
Answer:
the sum of IRV + TV + ERV representing the maximal achievable tidal volume

Question:
27. Lung compliance
Answer:
degree of lung expansion at any time is proportional to the change in pressure

Question:
28. Increased lung compliance
Answer:
smaller change in intrapleural pressure will increase lung volume greatly, causing easy inspiration
- this is not a good thing; easy to fill the lungs but it is harder to empty
- could be due to lack of elastic tissue

Question:
29. Decreased lung compliance
Answer:
need to generate a large intrapleural pressure than normal to cause an increase in lung volume
- large effort to inhale air; less stretchy lungs
- have a hard time inhaling, but easy to exhale due to more amount of elastic tissue and recoil

Question:
30. Pulmonary fibrosis
Answer:
Example of decreased lung compliance
- formation or development of excess fibrous connective tissue in the lungs
- due to inhalation of pollutants: metals, asbestos, certain gases
- due to infections
- idiopathic: age related, genetic predisposition