Delphinidin

Various small bodies distributed throughout the cytoplasm tend to give it a granular appearance. Examples of such components include types of small, spherical organelles called microbodies, which contain specialized enzymes and are bounded by a single membrane. Peroxisomes, for instance, contain enzymes needed by some plants to survive during hot conditions in a process called photorespiration, whereas glyoxisomes contain enzymes that aid in the conversion of fats to carbohydrates during, for example, the germination of seeds containing fats. If present, peroxisomes are generally found associated with chloroplasts, and glyoxisomes usually are located near mitochondria.

During a plant’s life cycle, peroxisomes and glyoxisomes may increase in number at stages when the need for them is greatest. At one time, lipid, fat, or wax droplets commonly found in cytoplasm were believed to be bounded by a membrane; recent evidence, however, suggests no membrane is present, and some, therefore, do not consider them true organelles.

Another organelle, called a lysosome, stores enzymes that digest proteins and certain other large molecules but is apparently confined to animal cells. The digestive activities of lysosomes are similar to those of the vacuoles of plant cells.