Some animals can produce a potassium ion concentration inside their cells that is twenty times greater than that of their environment. This ion concentration gradient is maintained by the plasma membrane.
Identify the source of energy used to maintain the concentration gradient. Where does this energy come from?

the major parts of the digestive system:

salivary glands.

pharynx.

esophagus.

stomach.

small intestine.

large intestine.

rectum.

accessory digestive organs: liver, gallbladder, pancreas.

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.

on island x the species needed to adapt because they were being subject to predators which didn't inhabit island y.