What are the two large branches of the airway which lead off the trachea at the tracheal bifurcation?

Options

A. Alveoli
B. Bronchi
C. Metavenules
D. Bronchioles

Explanation

To answer the question, "What are the two large branches of the airway which lead off the trachea at the tracheal bifurcation?", we can follow these steps:

### Step 1: Identify the Structure
The trachea, also known as the windpipe, is a single tube that conducts air from the larynx to the lungs.

**Hint:** Think about the main passageway for air before it reaches the lungs.

### Step 2: Understand the Bifurcation
At a specific point, the trachea bifurcates, or divides, into two branches. This occurs at the level of the fifth thoracic vertebra in the chest cavity.

**Hint:** Remember the location of the bifurcation; it’s important for understanding how air is distributed to both lungs.

### Step 3: Name the Branches
The two branches that the trachea divides into are known as the bronchi. More specifically, they are referred to as the primary bronchi.

**Hint:** Consider the terminology used in respiratory anatomy; "bronchi" refers to the main air passages that branch off the trachea.

### Step 4: Recognize Further Division
The primary bronchi will continue to divide into smaller branches called secondary bronchi, tertiary bronchi, and eventually lead to bronchioles within the lungs.

**Hint:** Think about the hierarchy of airway structures; the primary bronchi are just the beginning of a branching system.

### Final Answer
The two large branches of the airway that lead off the trachea at the tracheal bifurcation are called the **primary bronchi**.

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