Chapter 17.1, Problem 4AYLO

Summary Introduction

To discuss:

Similarities, difference, and interaction between the nervous and endocrine systems.

Introduction:

Hormones are chemical messengers secreted by glands into the extracellular fluids. The secreted hormones reach the target cells through the bloodstream, and they stimulate response of other tissues or cells. Hormones bind only to specific cells based on their corresponding receptors on cells, and they act through chemical signals. They regulate growth, development, blood pressure, metabolism, and fluid concentration, and they maintain homeostasis in the body. Both positive feedback and negative feedback mechanisms may regulate hormone pathways. The positive feedback amplifies the stimulus, whereas the negative feedback dampens the stimulus and stops the pathway.