Yes, all amino acids can exist as zwitterions under certain conditions, primarily at neutral pH levels. Amino acids are the building blocks of proteins and consist of a central carbon atom (alpha-carbon) bonded to an amino group, a carboxyl group, a hydrogen atom, and a variable R group. The amino group acts as a base by accepting protons, while the carboxyl group functions as an acid by donating protons. At physiological pH (around 7), both these functional groups become partially ionized: the amino group becomes positively charged (NH3⁺), and the carboxyl group becomes negatively charged (COO⁻). This creates a molecule with equal positive and negative charges, known as a zwitterion. Despite this overall neutrality, amino acids still exhibit different properties based on their R groups, which may also be charged or uncharged, hydrophobic or hydrophilic. Notably, the term "zwitterion" does not imply that all amino acids are identical; rather, it signifies their unique molecular structure with coexisting positive and negative charges.

Fragile Resin in Genshin Impact does not expire. Once you obtain it, this item remains in your inventory indefinitely until used. It is designed to restore 60 Original Resin, which is used for claiming rewards from Ley Line Blossoms, certain Domains, and Bosses. Players often save Fragile Resin for events or to farm materials from high-reward Domains efficiently. It's advisable to use them judiciously, especially since Original Resin is a key limiting factor in your daily progress within the game. Since it doesn't expire, you have the flexibility to use it as per your strategy and current needs.

Cellulose, a polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4) linked D-glucose units, is polar due to the presence of hydroxyl (–OH) groups attached to the glucose units. These hydroxyl groups form hydrogen bonds with water, making cellulose soluble in water and other polar solvents to a degree. The extensive hydrogen bonding is also responsible for the high tensile strength of cellulose fibers, which is why it is a critical structural component of the cell walls of plants and many algae. In practical applications, the polarity of cellulose is exploited in the production of paper, textiles, and in the pharmaceutical and food industries as a stabilizer, thickeners, and dietary fiber. Its polar nature makes cellulose interact well with water and other polar molecules, enhancing its versatility in industrial and nutritional uses. [Cellulose is polar due to its many hydroxyl groups, which enable hydrogen bonding with water, contributing to its solubility in polar solvents and functional versatility in various industries.]