Which cell organelle secretes zymogen granules?

Concept: Smooth endoplasmic reticulum secrete Zymogen.

Zymogen is a proenzyme that becomes active after a hydrolysis reaction. 

Smooth endoplasmic reticulum secreteszymogen.

Lipids,steroids,and  phospholipids also secreted by smooth E.R.Endoplasmic reticulum is made of a network of membranes,cisternae,held together by cisternae . 

Spherosomes are a single membrane and store and synthesize lipids. Lysosomes contain enzymes that break down proteins and lipids. 

Golgi bodies transport,modify and pack proteins and lipids into vesicles .