What types of cells are excitable cells?

Excitable cells refer to a specific type of cells in the body that have the unique ability to generate and conduct electrical impulses. These cells play a key role in transmitting signals within the nervous system, which is crucial for various physiological processes. There are two main types of excitable cells – neurons and skeletal muscle cells. 

1. Neurons or Nerve Cells - Neurons, which are the primary excitable cells of the nervous system, have polarized membranes. The neuron gets electrically activated when the polarity shifts due to various ions coming in contact with the membrane. This ability to become polarized and depolarized is responsible for transmitting electrical signals, also known as nerve impulses or action potentials.  These excitable cells are essential for several critical functions including motor control, sensory perception, and cognitive processes such as memory and thinking. 
2. Muscle Cells - Muscle cells, skeletal muscle cells and cardiac muscle cells in particular, are another type of excitable cells. Skeletal muscle cells are responsible for voluntary muscle movements whereas cardiac muscle cells, which are found only in the heart, control involuntary contractions. Both skeletal and cardiac muscle cells contract in response to electrical signals. This contraction generates force and movement.