Pregnancy. This hormone is also produced by some cancerous tumors.
Explanation:
There is a massive variety of different types of fruit. The main separation between fruit types is between fleshy and dry fruits. Fleshy fruits have a juicy layer of tissue in the pericarp, seen in fruits such as oranges, tomatoes and grapes; whereas dry fruits do not
Internal means its on the inside
external means its on the outside
so an internal regulator is when the proteins respond to events on the inside of a cell
and an external regulator is when the proteins respond to events outside the cell