Because the membrane is selective in what can cross through it, it considered______.
Larger molecules and substances moving against the concentration gradient must be moved through the membrane by______.
Some of the membrane proteins have carbohydrate receptors called______ attached to help cells in recognize each other certain molecules. One role of peripheral proteins can be to act as anchors for the________. Some integral proteins aid in_________and in ________. Integral proteins that move molecules through the membrane are also called________proteins.