The answer is B because:
Cell walls are made of cellulose and proteins (hence II).
Animal cells don't have cell walls (only cell membrane) but plant cells do so IV
They must be semipermeable since materials for example carbon dioxide and water for photosynthesis have to go into the cell <em>some</em> way.
Answer:
C.) crystalline solids
Explanation:
The solid materials may be crystalline or amorphous. The concept of crystal structure is related to the organization of atoms in a geometrical form. Crystalline structures are present in various materials, where atoms distributed within their structure form a network called the crystalline lattice. Therefore, crystalline structures have salts, metals and most minerals. Crystalline structures are formed by unit cells that are their basic unit, as they constitute the smallest set of associated atoms found in a crystalline structure.
The molecules of the crystalline structures can have two types of bonds, the directional ones, which include the covalent and dipole dipole and the non-directional ones where the metallic, ionic, van der Walls bonds. When formed by ionic compounds, these crystalline structures can result in crystalline solids.
