The following CSS properties will be explained: 1  color. 2  background-color. 3  background-image.  background- 1 repeat. background-attachment.  background- 1 position. background.
The transmission of a signal through the nervous system can also be considered an example of long-distance signaling. Local signaling in plants is not well understood. Because of their cell walls, plants must have different mechanisms from animals. Plants and animals use hormones for long-distance signaling. In animals, specialized endocrine cells release hormones into the circulatory system, by which they travel to target cells in other parts of the body. Plant hormones, called growth regulators, may travel in vessels but more often travel from cell to cell or move through air by diffusion.
3. Intercellular chemical signals secreted into the circulatory system; carried to organs they control, where they bind to receptors and produce a response. 4. Intercellular chemical signals, secreted by nerve cells; important in the function of the nervous system.