Here's a breakdown:

* Muscle cells: These cells are responsible for movement in animals. They can contract and relax, allowing for locomotion, internal organ function, and other physical activities.

* Nerve cells: These cells form the nervous system, responsible for communication and coordination throughout the body. They transmit signals rapidly, enabling animals to react to stimuli and control their actions.

While plants can exhibit movement in certain ways (e.g., growth towards light), they lack the specialized cells that allow for the complex, coordinated movements found in animals.