11. Compare and contrast the Rough ER and the Smooth ER. (Structure and
function)
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The rough er has ribosomes attached to it and the smooth er does not

i'd say that the moon rock is about 2.2 billion years old.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.