The thoracic cavity contains the lungs and the heart (the heart is located within the mediastinum which is the central compartment of the thoracic cavity). The diaphragm forms the floor of the thoracic cavity and separates it from the more inferior abdominopelvic cavity. The abdominopelvic cavity is the largest cavity in the body. The thoracic cavity is protected by the thoracic wall which consists of the ribcage and associated skin, muscle, and fascia. The cranial and vertebral cavities are the dorsal cavities in which the central nervous system are encased.

The trachea (windpipe) is a tube that connects the pharynx and larynx to the lungs, allowing for the passage of air. The trachea extends from the larynx and branches into the two primary bronchi. There is a right bronchus and a left bronchus and these branch into secondary and tertiary bronchi which branch into smaller tubes, known as bronchioles, then eventually to terminal bronchioles. No gas exchange occurs in the bronchi. The first site of gas exchange is the respiratory bronchioles, which lead into alveolar ducts, alveolar sacs, and alveoli.

At the top of the trachea the cricoid cartilage attaches it to the larynx. The epiglottis closes the opening of the larynx during swallowing. 

The medial surface of the right lung lies adjacent only to heart, inferior and superior vena cava, azygos vein, and esophagus. The medial surface of the left lung lies adjacent to heart, aortic arch, thoracic arch, and esophagus.

The lingula is a tongue shaped portion of the upper lobe of the left lung. The left lung only has two lobes (upper and lower), which are divided by an oblique fissure. The left lung also has a cardiac impression, a cardiac notch, and groves for various parts of the aorta and other vasculature.

The right lung has three lobes (upper, middle, and lower). The right lung is larger than the left but it is shorter since the right dome of the diaphragm is higher (due to the liver).

The adrenal (suprarenal) glands are trianglular glands situated above the kidneys. They are retroperitoneal and are surrounded by a capsule and renal fascia. The adrenal glands have a cortex (this makes mineralcorticoids (aldosterone), glucocorticoids (cortisol), and sex hormones). The adrenal glands also have a medulla that secretes epinephrine and norepinephrine. 

Type 1 pneumocytes (alveolar cells) are responsible for gas exchange between the alveoli and blood. They have a thin cytoplasm. Type 2 pneumocytes also reside in the alveoli, but they produce surfactant which prevents the alveoli from collapsing. Macrophages and neutrophils can be present in the alveoli or lung blood vessels, but they do not participate in gas exchange,but are involved in the response against microbial infections. Oligodendrocytes are neuroglia in the central nervous system that produce myelin sheets.

The adrenal gland functions purely as an endocrine gland, while the other choices do not. The pancreas and stomach contain endocrine cells, but they also function in digestion; they are not  purely endocrine glands. The ovary also contains endocrine cells, but it also functions in reproduction and is thus not a purely endocrine gland.

Oxygen and carbon dioxide are exchanged across the thin walls of the air sacs, or alveoli. The nasal cavity, bronchi, and trachea are responsible for filtering, humidifying, and warming the air passing through them. They do not function in gas exchange.

Of the pneumocytes, type II cells are responsible for secreting pulmonary surfactant, serve as precursors to type I cells, proliferate during lung damage and decrease alveolar surface tension.

Type I cells, on the other hand, line the aveoli and consist of 97% of the alveolar surface. The cells are squamous and thin for optimal gas diffusion. 

An easy way to differentiate between the two types of lung cells is to remember that type I cells are responsible for the physical lining and makeup of pneumocytes, while type II cells are responsible for the functioning of the pneumocytes.

The right lung has 3 lobes: superior lobe, middle lobe and inferior lobe.

The left lung has 2 lobes: superior lobe and inferior lobe. There is no middle lobe in the left lung because this space in the left lung is occupied by the heart.