5. Complete the sentences to describe some important examples of active transport.

The concentration of glucose molecules in the ___________ of the
small intestine is ___________ than the concentration inside the
intestinal villi. This means that glucose would ___________ from the
villi into the lumen, but this can’t happen because the body needs to take
in the glucose, not lose it. Instead, special ___________ proteins in
the cell membrane use ___________ to move the glucose into the villi
against its ___________ gradient.
Similarly, the amount of glucose inside of the blood in the kidneys is
___________ than it is in the tubule, but it must move out of the
tubule. Glucose moves into the blood by ___________
___________.