Accessory pigments, also known as antenna pigments, play a crucial role in photosynthesis alongside chlorophyll. They are primarily found in the chloroplasts of plants, algae, and some bacteria. These pigments include carotenoids, phycobilins, and other compounds that absorb light energy outside chlorophyll's absorption spectrum, mainly in the green-yellow and far-red regions. This broadened absorption range allows organisms to capture more sunlight, especially under low-light conditions, improving their efficiency in converting light into chemical energy. Accessory pigments also protect cells from damage by filtering out harmful wavelengths and dissipating excess energy as heat through a process called non-photochemical quenching. Without these pigments, photosynthetic organisms would be less adaptable to varying light environments and more susceptible to photodamage.

Casting polymer bullets involves mixing a polymer resin with a hardener, pouring it into bullet molds, and allowing it to cure. Safety equipment such as gloves and eyewear is essential due to the chemicals involved. First, select a bullet mold of your desired caliber and design. Then, prepare the polymer mixture according to the manufacturer's instructions, usually involving combining specific ratios of resin and hardener. Mix thoroughly to ensure a consistent blend. Gently pour the mixture into the molds, taking care to avoid air bubbles, which can create weak spots in the bullets. Allow the bullets to cure as per the resin specifications, which could range from a few hours to overnight. Once cured, carefully remove the bullets from the molds. These bullets are primarily used for non-lethal or training purposes, as they do not have the same ballistic properties as traditional lead or metal bullets. Experimenting with different resin types can yield various hardness and flexibility levels, allowing for customization according to specific needs.

Polymer volume fraction graphs are skewed left (negatively skewed) primarily due to the nature of their physical interactions and the distribution of molecular weight. In a polymer solution, as the volume fraction increases, the space available for the polymer chains decreases, leading to more entanglements and physical interactions. This results in a rapid increase in properties such as viscosity or modulus at higher concentrations, leading to a tailing effect towards the higher volume fractions. Additionally, polymers often have a distribution of molecular weights (polydispersity). The presence of higher molecular weight species in smaller fractions can contribute significantly to the properties measured, further skewing the graph left. These effects are more pronounced when observing properties that are highly sensitive to the entanglement and physical interactions between polymer chains, such as rheological properties.