Sensory cells in the human eye can detect changes in light. The information obtained from these sensory cells is transmitted to the brain through neurons, and the brain determines the correct behavioral response. For example, if the intensity of light being detected by a person's eye rapidly increases, the nervous system might transmit information to the eye that causes the eyelid to close and block out the light. This is an example of a behavioral response that

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.

1. is geographic distribution

2 is increasing complexity

3 is transitional forms