Chapter 6 Self-check questions and answers

6.1 What does pseudostratification mean?

‘Pseudo’ means false or apparent; ‘stratified’ means layered. Pseudostratification describes the apparent multilayering (stratification) of cells exhibited by certain types of epithelium

6.2 Name the four main cell types that hat can be seen with a light microscope.
a) Ciliated columnar cells, b) mucus-secreting goblet cells, c) basal cells and d) neuroendocrine cells.

6.3
The function of mucus secreted by the goblet cells is to:
E) All of the above

6.4 Name the cells that make up the olfactory epithelium.
Supporting cells, basal cells and olfactory cells

6.5
The function of lining of nasal cavity include:
E) All of the above

6.6 What are the supposed purposes of paranasal sinuses?

Possible functions include humidifying and warming the inhaled air and reducing the weight of the skull. They may also play a role in speech by resonating the sound emitted from the vocal cords and by affecting the tone of the voice.

6.7
Perceived function of paranasal sinuses
E) All of above

6.8 What is the function of the epiglottis ?
During the swallowing process, the epiglottis folds down and temporarily blocks the opening to the trachea as food travels to the oesophagus. This action keeps food from entering the lung.

6.9
The true vocal cords are:
B) Composed of elastic fibers covered with simple squamous epithelium

6.10 Why does the trachea have cartilage rings?
The 'C' shaped cartilage rings are present in the trachea to prevent it from collapsing, and they keep the trachea open during the breathing.

6.11
The trachea has:
C) Pseudostratified columnar epithelium

6.12
The lungs are separated from each other by
E) Mediastinum

6.13
The large bronchi are lined by
D) Pseudostratified ciliated epithelium

6.14 What structures enter/leave the lungs at the hilum?

Pulmonary, pulmonary veins and lymphatic vessels enter the lungs at the hilum

6.15 What mechanism regulates the diameter of the bronchioles?

The walls of the bronchioles do not contain cartilage, but instead contain smooth muscles that can increase or decrease the diameter of the bronchioles in response to signals from the autonomic nervous system. Parasympathetic stimulation causes smooth muscle contraction (bronchoconstriction) while sympathetic stimulation causes relaxation of smooth muscle, leading to bronchodilation.

6.16
The epithelium of large bronchioles is lined by
D) Ciliated pseudostratified columnar

6.17 What do you understand by the blood-air barrier

The blood-air barrier is found in the alveoli. It exists to prevent air bubbles from forming in the blood, and from blood entering the alveoli. The barrier is permeable to oxygen, carbon dioxide, carbon monoxide and many other gases.

6.18
The function of a type 1 pneumocyte is:
C) Gaseous exchange

6.19
Alveolar macrophages are derived from:
D) Monocytes

6.20 What is the function of serous fluid and how is it produced?

Serous fluid acts as a lubricant, which allows movement of the organs in the body cavity such as the beating of the heart, movement of the bowel, and expansion and contraction of the lungs. The fluid is formed by filtration of plasma through the capillary endothelium.

6.21
The pleura is:
E) All of the above