Explanation:
I'm not sure but look online for the answers
When SA Node triggers Atria goes into Systole !! and when the signal reaches to AV node and from there it goes to Bundle of His making Ventricle to systole or constrict !!
So your answer is Systole !!
IN THE LUMEN INSIDE OF THE ENDOPLASMIC RECTICULUM.
<u>Explanation:</u>
The endoplasmic recticulum is the continuous membrane system that forms that forms the more number of flattened within the cytoplasm of eukaryotic cells and performs the multiple process in the cell.
The immportant functions of endoplasmic recticulum is folding, synthesis, modification, ans transport of the protein. The lumen is the protein which is present in the endoplasmic recticulum.
The lumen of the endoplasmic recticulum is the area closed by the endoplasmic recticulum membrane, it is an extensive network of the membrane tubues, visicles, and flattened the cisternae found in the eukaryotic cells.
They are made of some of the same matter