Sap activity, which transforms excess ingested sugar into long-chain oligosaccharides." A much larger set of animals do however consume phloem sap by proxy, either "through feeding on the honeydew of phloem-feeding hemipterans. Honeydew is physiologically less extreme than phloem sap, with a higher essential:non-essential amino acid ratio and lower osmotic pressure," or by feeding on the biomass of insects that have grown on more direct ingestion of phloem sap. Maple syrup is made from reduced sugar maple xylem sap. The sap often is harvested from the Sugar Maple, "Acer saccharum". In some countries (e.g., Lithuania, Latvia, Estonia, Finland, Belarus, Russia) harvesting
Plant secretory tissue gland may consist of isolated cells or small group cells with or without a central cavity. They are of various kinds and may be internal or external. Internal glands are External glands are commonly short hairs tipped by glands. They are Plant secretory tissue The tissues that are concerned with the secretion of gums, resins, volatile oils, nectar latex, and other substances in plants are called secretory tissues These tissues are divided into two groups- Cells or organizations of cells which produce a variety of secretions. The secreted substance may remain deposited within the secretory cell itself or may be