The sodium potassium pump is a form of active transport that moves three sodium ions to the outside of the cell for every two potassium ions that is moved into the cell. Which of these best explains why energy is needed for active transport?

Ions are negatively charged

Ions are attached to large proteins

Ions are trapped inside the plasma membrane

Ions are moved against the concentration gradient

i got you i did it ya know what it is just needing to fill this in for a quick task!

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.

d. cellulose and starch