Solution. 1  This species has a 2â charge on it, so it is an anion. Anions are named using the stem of the element name with the suffix -ide added. 2  Because this species has no charge, it is an atom in its elemental form. This is cobalt. 3  In this case, there is a 2+ charge on the atom, so it is a cation.
1. 2. 3. The walls of the alveoli are composed of a single layer of flattened epithelial cells, as are the walls of the capillaries, so gases need to diffuse through just two thin cells. The alveoli walls are kept moist by water diffusing from the surrounding cells.he walls of the alveoli are composed of a single layer of flattened epithelial cells, as are the walls of the capillaries, so gases need to diffuse through just two thin cells. The alveoli walls are kept moist by water diffusing from the surrounding cells.
assume there is a higher concentration of each of the following substances in the extracellular fluid surrounding a cell than in the cell s cytoplasm predict whether the substance would be more likely to enter the cell by simple diffusion or by facilitated diffusion and explain why is o2 more likely to enter the cell by simple diffusion or facilitated diffusion dialysis tubing is composed of a selectively permeable membrane is a membrane that allows some substances to pass through easily while other substances pass through very slowly or not at all all cell membranes including the plasma membrane are selectively permeable simple diffusion refers to diffusion of substances without the help of transport proteins facilitated diffusion refers to diffusion of substances with the help of transport proteins