I believe the answer is receptor sites, but correct me if I'm wrong.
Hope this helps!
The network of glands that release chemical messengers directly into the bloodstream is called the endocrine system. The endocrine system produces and secretes t<span>hese chemical messengers, referred as </span>hormones directly into bloodstream to transmit signals to appropriate part of body. The hormones regulate bodily functions like growth, metabolism, <span>tissue function, sexual function, reproduction, </span>sleep and mood.
In the small intestine, these cells contain microvilli, which are tiny hair-like projections that increase nutrient absorption. These projections increase the surface area of the small intestine allowing more area for nutrients to be absorbed.
C- been tested many different times by different scientist