Lecture 31 Structure and Mechanisms of the Respiratory System.

Question 1

Identify the organs of the Respiratory System.

Answer 1

Nose.
Mouth.
Throat (pharynx)
Voice box (larynx)
Windpipe (trachea)
Large airways (bronchi)
Small airways (bronchioles)
Lungs.

Question 2

Differentiate between the three regions of the pharynx and describe their roles in the respiration.

Answer 2

The nasopharynx is located at the back of the nasal cavity and provides a connection between it and the oropharynx.
The oropharynx or ‘common gorge’ connects the buccal cavity (mouth) with the nasopharynx, so that swallowing food and breathing have to pass through the same passage way. This is why you sometimes choke on your food. The swallow reflex suspends breathing while food is being swallowed.
The glottis is an opening into the larynx or “voice box” from the oropharynx. It is at the beginning of the larynx, which passes down through the trachea (the windpipe) to the lungs

Question 3

Identify the anatomical features of the larynx related to respiration and vocalization.

Answer 3

The glottis is an opening into the larynx or “voice box” from the oropharynx. It is at the beginning of the larynx, which passes down through the trachea (the windpipe) to the lungs

Question 4

Describe the mechanisms of external and internal respiration based on differences in partial pressures of o2 and cO2.

Answer 4

External respiration occurs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses into the alveolar air. Internal respiration occurs in the metabolizing tissues, where oxygen diffuses out of the blood and carbon dioxide diffuses out of the cells.

Question 5

Purpose of the nasal cavity

Answer 5

The purpose of the nasal cavity is to warm, humidify and filter the air before it passes into the trachea and lungs.
The superior, medial and inferior nasal conchae are covered with a mucous lining and hairs, which trap small particles and are periodically expelled.
The paranasal sinuses (ethmoid, sphenoid and maxillary) are also lined by mucous membranes that help in the filtration and humidifying process. The chambers also act to amplify the voice (which is why you sound funny with a stuffy nose)

Question 6

Describe the structure and location of the tubes that form the bronchial tree.

Answer 6

Right primary bronchus, right secondary bronchi, right tertiarty bronchii.

Question 7

Describe the structure and location of the tubes that form the bronchial tree.

Answer 7

Right primary bronchus, right secondary bronchi, right tertiary bronchii.

left primary bronchus, left secondary bronchi, left tertiary bronchi.

Question 8

Identify the coverings and the gross anatomical features of the lungs.

Answer 8

Base lung, diaphragm,

Question 9

Describe the role of the respiratory membrane in diffusion of the respiratory gases.

Answer 9

tbd

Question 10

Structure of aveolus.

Answer 10

About 90% of the walls of the alveolus are made up of squamous epithelium, called Type I cells. These are best adapted to transpiration.
The remaining 10% are cuboidal epithelial cells called Type II alveolar cells. These produce a surfactant, which coats the inner alveolar walls, preventing the alveoli from collapsing entirely (such a condition is considered pathological and is called atelectasis)
There are also wandering macrophages in the alveoli, which engulf any debris that has made it into them.