9.1. The function of interaction
The function of interaction consists on getting all the information from the outside and inside of the organism (using for it the sensory receptors), evaluating that information and generating responses.
The function of interaction is carried out by the coordination systems, which are the nervous system and the endocrine system. Both systems work fully coordinated. The differences between them are:
The nerve impulses (electrically) transmit the information
The hormones (chemically) transmit the information
The responses are very fast but their duration is very short
The responses are slow but their duration is very long
The nerve impulses are carried by the neurons
The hormones are carried by blood
The nerve impulses affect very specific organs or cells
The hormones can affect a lot of organs
9.2. The nervous path
The sensory receptors get the information from the inside or outside of the body in the form of stimuli. A stimulus is a detectable change. After detecting it, the receptor sends the information of the stimulus as a nerve impulse to the Central Nervous System (CNS) where an answer is created. Answers can be motor (movements made by the muscles) or secretory (glands that secrete hormones).
The basic nervous path can be resumed as:
9.3. The sensory receptors
The sensory receptors are the responsible of capturing information from the outside (extereceptors) or inside (the interoreceptors) of the body. Depending on the type of stimulus they can detect, we distinguish different types of receptors:
LOCATED IN OR ON..
skin / ears
physical stimuli: touch, pressure,sound,waves...
retina of eye
Throughoug the body