The nose, pharynx, larynx, trachea and bronchi all work like a system of pipes through which the air is funnelled down into our lungs. There, in very small air sacs called alveoli, oxygen is brought into the bloodstream and carbon dioxide is pushed from the blood out into the air.
And, just to clarify, the kitty litter in your trunk, to be used for traction, needs to be taken out and spread around your tires. Most cars are front wheel drive, so the extra weight alone in the back ain't gonna do you much good.
The House Rabbit Society suggests one of the many organic paper litters available. Sometimes the strong scent of litter will keep bunny out of the box. Avoid pine and cedar shavings and clay cat litters. Also, try a good amount of fresh hay in the box.