The circulatory system and respiratory system are protected by your skin, muscles, and ribs.
Transport proteins (carrier proteins and channel proteins) allow substances into and out of the cell that cannot pass through the phospholipid bilayer (as they’re either to large, charged or not lipid soluble) by facilitated diffusion.
Specifically channel proteins allow ions into and out of the cell by creating a pore in the membrane in which they can move through with their concentration gradient
Cell saps are the liquid inside of a plant cell's large central vacuole, which acts as support in order for it to function. They're made up of amino acids, glucose, salts and water and plays an important role in osmosis.
Cytoplasms, on the other hand, are a jelly-like substance between the cell membrane and nuclear envelope within a eukaryotic cell. They're mostly made up of water and salt, and aid in growth and metabolism in a cell.
