00:01
Which of these does not use the muscular system? the secretion of hormones from glands, the grinding of the stomach, running up a hill, or lifting a heavy box.
00:13
So, c and d, we can roll out, those definitely use the muscular system because those use the skeletal muscle.
00:20
So c and d use skeletal muscle.
00:24
What about the other two? well, other two, the one that actually uses muscles is b.
00:29
So when you eat food, your stomach churns, and this churning requires smooth muscle.
00:38
So the muscle in the walls of the stomach is contracting and relaxing, and this movement moves the food around, grinds it up.
00:48
However, the secretion of hormones does not require muscles.
00:53
So the secretion of hormones, you have a duct, so let's say this is a duct, and it is surrounded by cells, and the cells just secrete the protein directly into the duct.
01:09
So all of these secrete the product into the duct, so it can flow to wherever it's needed.
01:18
And later on, there may be the use of muscles to move it around or to store it, but the actual secretion from the glands is not related to the muscular system.
01:29
So for example, this could be perhaps pancreas, and these could be producing insulin...