The statement that the trachea bifurcates into the right and left main bronchus at the carina is true. The carina is the internal prominence or ridge where the trachea divides into the right and left bronchi, leading air to the lungs’ bronchial tree for gas exchange. This bifurcation is a crucial step in the respiratory process, marking the point where the air passage branches out towards the lungs. The right lung typically has three lobes and is larger than the left lung, which has two lobes to accommodate the heart’s placement within the chest cavity. The trachea and bronchi are supported by incomplete rings of cartilage to ensure they remain open for air passage. The carina is lined with cilia and mucus cells to trap debris and pathogens, facilitating a clean air passageway into the lungs.
