Answer:
Stem cells are divided into 2 main forms. They are embryonic stem cells and adult stem cells. Embryonic stem cells.
One
substance, other than the secretions from nerve cells, that is used in cell
communication are hormones.
<span>
To
add, <span>a hormone is any member of a class of signaling
molecules produced by glands in multicellular organisms that are transported by
the circulatory system to target distant organs to regulate physiology and
behaviour.</span></span>
A group of similar (accoding to function) types of cells, when comes together to perform a specific function, then it forms a tissues.
When a group of similarly working tissues come together then they form an organ.
And this relation could be written as
cell > tissue > organ
So, organ is a collection of tissues and tissues are collection of cells.
Explanation:
cells must be attached to a substrate or extracellular matrix of a tissue.