Snakes breathe through their lungs.

Explanation:
Snakes, like most reptiles, have lungs for respiration. Lungs are the primary respiratory organs in snakes, allowing them to take in oxygen and release carbon dioxide. Here is a detailed explanation of how snakes use their lungs for breathing:

1. Lung Structure:
Snakes have a pair of elongated lungs located in their chest cavity. The lungs are made up of numerous small sacs called alveoli, which are surrounded by blood vessels. These alveoli provide a large surface area for the exchange of gases.

2. Inhalation:
When a snake breathes in, it expands its ribcage, creating more space in its chest cavity. This expansion allows the snake to draw air into its lungs. The air enters through the nostrils and travels down the trachea, a tube that connects the nostrils to the lungs.

3. Gas Exchange:
Inside the lungs, oxygen from the inhaled air diffuses across the walls of the alveoli and into the surrounding blood vessels. At the same time, carbon dioxide, which is a waste product of cellular respiration, moves from the blood vessels into the alveoli. This exchange of gases is facilitated by the thin and moist walls of the alveoli, which allow for efficient diffusion.

4. Exhalation:
After the gas exchange has occurred, the snake exhales by contracting its ribcage and pushing air out of its lungs. The carbon dioxide-rich air is expelled through the nostrils.

5. Respiratory Rate:
The respiratory rate of a snake can vary depending on factors such as activity level, temperature, and metabolic rate. When a snake is resting, its respiratory rate is generally slower compared to when it is active or digesting food.

In conclusion, snakes breathe through their lungs, just like most other reptiles. Their lungs allow them to exchange gases with the environment, taking in oxygen and releasing carbon dioxide.