Fact 1: Some touch receptors sense differences in temperature or pain.

Fact 2: Touch receptors are free nerve endings or nerve endings that are surrounded by a capsule.

Given the two facts above, answer the question "What senses differences in temperature?" with the following options: 
- the skin
 - Electric devices
 - animals
 - an electric stove
 - nerve endings
 - an organism's body
 - Most plants
 - peachleaf willow


 

     nerve endings    