The kinetic theory assumes that collisions of gas particles are perfectly elastic. what does this statement mean?

For example: if a car collides head first into each other, they would just kinda stay in that same position that they collided in because they are not elastic. But since gas particles are elastic, they would just bounce right off of each other and walls as if they didn't hit anything.

It is called the medulla oblongata or people usually call it medulla. it is the lower half of the brain stem continuous with the spinal cord.