Anatomy and Physiology

Answer:

Part (a) corresponds to the pulmonary capillary, the small vascular network that connects to the pulmonary circuit. Part (b) corresponds to the respiratory membrane, which lines vascular structures.
Part (c) refers to the alveolus, a small sac that provides the space where gas exchange can take place. Part (d) represents the interstitial fluid, the solution surrounding cells between tissues, providing nutrients and a pathway for removing wastes. Part (e) indicates the systemic capillary.
The pink arrows represent the direction and movement of oxygen, while the light blue arrows represent the diffusion of carbon dioxide.

Answer:

The respiratory system is composed of air-conducting and respiratory portions, with the following functions:
1. Provide large area for gas exchange between air and blood
2. Move air to and from gas-exchange surfaces of lungs
3. Protect respiratory surfaces from dehydration and temperature changes
4. Produce sounds permitting speech and communication
5. Aid sense of smell by olfactory receptors

Answer:

The epiglottis is a structure shaped like a shoehorn that extends above the glottis. The epiglottis folds over the glottis during swallowing, which prevents liquids or foods from entering the respiratory passages.
Thus, the correct answer is option (c).
The glottis refers to the narrow opening, through which air leaves the pharynx. Choice (a) is eliminated since the glottis is merely a passageway in the respiratory tract.
Choice (b) does not make sense because arytenoid cartilage is one of the three pairs of cartilage making up the larynx. The larynx is a structure that allows air to be inhaled through the respiratory tract.
The thyroid cartilage is a curving structure that makes up the anterior and lateral surfaces of the larynx. This eliminates (d) given that it has no structural component that would function in blocking food from the respiratory tract.