The purpose of the cough and sneeze reflexes is to clear the airway.

Choice A rationale

Plaque formation in arteries does not start with platelets and fibrin.

Choice B rationale

Plaque begins with fatty streaks, which are the earliest signs of atherosclerosis and consist of lipid-laden cells in the arterial wall.

Choice C rationale

White blood cells are involved in the inflammatory process of atherosclerosis but do not represent the initial plaque formation.

Choice D rationale

Foam cells, which are lipid-laden macrophages, develop later in the process of plaque formation and contribute to the growth of atherosclerotic lesions. .

Choice A rationale

The auricle is an ear-shaped appendage on the surface of the atrium and does not separate the right and left halves of the heart. Its function is to increase the capacity of the atrium, allowing for more blood to be collected and passed to the ventricles.

Choice B rationale

Syncytia refer to a multinucleated cell that can result from the fusion of multiple cells, which is not a structure that separates the right and left sides of the heart. They are typically related to muscle tissue and coordinated contractions.

Choice C rationale

The Bundle of His is a collection of heart muscle cells specialized for electrical conduction that transmits the electrical impulses from the AV node to the point of the apex of the fascicular branches. It does not act as a separator between the right and left halves of the heart.

Choice D rationale

The septum is the structure that separates the right and left halves of the heart. It is a robust wall that divides the atria (interatrial septum) and the ventricles (interventricular septum), ensuring the segregation of oxygenated and deoxygenated blood.