Week 4 - Homework #7

Question 1

What structure is formed when a terminal bronchiole branches?

A. an alveolar duct
B. alveoli
C. respiratory bronchioles
D. all of the above

Answer 1

C. respiratory bronchioles

Question 2

The lungs do not normally collapse because of:

A. surfactant
B. intrapleural pressure
C. elastic recoil
D. both a and b

Answer 2

D. both a and b

Question 3

Anatomists consider the bronchioles to begin and bronchi to end when:

A. the airway diameter becomes smaller than 1mm
B. tissue thickness permits gas diffusion
C. only a single layer of epithelial tissue defines the structure
D. cartilaginous reinforcements are reduced to simple rings rather than the complex plates seen above
E. smooth muscle is entirely replaced with CT

Answer 3

D. cartilaginous reinforcements are reduced to simple rings rather than the complex plates seen above

Question 4

Immediately after the creation of an opening through the thorax into the pleural cavity:

A. air flows through the hole and into the pleural cavity
B. air flows through the hole and out of the pleural cavity
C. air flows neither into nor out of the pleural cavity
D. the lung protrudes through the opening

Answer 4

A. air flows through the hole and into the pleural cavity

Question 5

Atmospheric pressure is 760 mmHg, and its composition is 20.9% oxygen, 0.04% Carbon dioxide, 5% water vapor, and 74.1% nitrogen. The partial pressure of oxygen is:

A. 15.2 mmHg
B. 20 mmHg
C. 118 mmHg
D. 160 mmHg
E. 760 mmHg

Answer 5

D. 160 mmHg

Question 6

The rate of diffusion of any gas across the respiratory membrane increases when the:

A. respiratory membrane becomes thicker
B. surface area decreases
C. partial pressure gradient for the gas increases
D. diffusion coefficient for the gas decreases

Answer 6

C. partial pressure gradient for the gas increases

Question 7

The partial pressure of CO2 in the venous blood is:

A. greater than in the tissues
B. equal to the tissues
C. Less than the aveoli
D. less than the arterial blood

Answer 7

B. equal to the tissues

Question 8

The parietal pleura:

A. covers the surface of the lung
B. covers the inner surface of the thoracic cavity
C. is the CT partition that divides the thoracic cavity into the right and left pleural cavities.
D. covers the inner surface of the alveoli
E. is the membrane across which gas exchange occurs

Answer 8

C. is the CT partition that divides the thoracic cavity into the right and left pleural cavities.

Question 9

An acute infection of the throat that can cause swelling and closure of the glottis (causing suffocation) is:

A. laryngitis
B. laryngospasm
C. acute epiglottitis
D. strep throat
E. acute pharyngitis

Answer 9

C. acute epiglottitis

Question 10

Sympathetic input to the smooth muscle in the bronchioles causes all of the following except:

A. bronchoconstriction
B. an increase in lumen diameter
C. a reduction in airway resistance
D. relaxation of bronchiolar smooth muscle

Answer 10

A. bronchoconstriction

Question 11

During quiet breathing:

A. both inspiration and expiration require muscle contraction
B. inspiration is passive while expiration requires muscle contraction
C. inspiration requires muscle contraction while expiration is passive

Answer 11

C. inspiration requires muscle contraction while expiration is passive