Which statement defines active transport?
1 )
movement of large molecules through the cell surface membrane into the cytoplasm of a cell
movement of molecules or ions from where they are in a low concentration to where they are in a higher concentration
3 )
movement of molecules or ions from where they are in a high concentration to where they are in a lower concentration
4 )
net movement of water molecules across a partially permeable membrane from a region of higher water potential to one of lower water potential
