Tips. 1  If you want to focus on a particular muscle area, you can do so by changing the stride length. 2  For an elliptical with multiple users, use one whose stride length is adjustable to accommodate different heights. 3  Do not rely solely on guidelines.
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.
all of the following are true of the nervous system, except. function independently of the endocrine system. endocrine cells. release their secretions directly into body fluids. ____ are chemical messengers that are released in one tissue and transported in the bloodstream to alter the activities of specific cells in other tissues. hormones.