You are presented with the question "Cells obtain energy from the blood with the help of" and the following answer choices: 
- sweating
 - batteries
 - pancreas
 - electron
 - insulin
 - alveoli
 - oxygen
 - sunlight

Now knowing that insulin helps cells take up glucose from the blood and blood Glucose Blood Glucose Glucose is the principal source of energy for mammalian cells, choose the best answer.


 

     insulin    