detailed diagram
of vacuoles
Answers
Answer:
vacuole is a membrane-bound organelle which is present in all plant and fungal cells and some protist, animal and bacterial cells
PLZZ MARK ME AS BRAINLIST ✌✌
Explanation:
Vacuoles Definition
A vacuole is a membrane-bound organelle that is present in all plant and fungal cells and some protist, animal and bacterial cells.
The most conspicuous compartment in most plant cells is a very large, fluid-filled vacuole. Large vacuoles are also found in three genera of filamentous sulfur bacteria, the Thioploca, Beggiatoa, and Thiomargarita.
However, the function and significance of vacuoles vary greatly according to the type of cell having much greater prominence in the cells of plants, fungi, and certain protists than those of animals and bacteria.
There may be several vacuoles in a single cell. Each vacuole is separated from the cytoplasm by a single unit membrane, called the tonoplast.
Generally, they occupy more than 30 percent of the cell volume; but this may vary from 5 percent to 90 percent, depending on the cell type.
Structure of Vacuoles
They generally have no basic shape or size; its structure varies according to the requirements of the cell.
In immature and actively dividing plant cells the vacuoles are quite small. These vacuoles arise initially in young dividing cells, probably by the progressive fusion of vesicles derived from the Golgi apparatus.
A vacuole is surrounded by a membrane called the tonoplast or vacuolar membrane and filled with cell sap.
The tonoplast is the cytoplasmic membrane surrounding a vacuole, separating the vacuolar contents from the cell’s cytoplasm. As a membrane, it is mainly involved in regulating the movements of ions around the cell, and isolating materials that might be harmful or a threat to the cell.
Vacuoles are structurally and functionally related to lysosomes in animal cells and may contain a wide range of hydrolytic enzymes. In addition, they usually contain sugars, salts, acids and nitrogenous compounds such as alkaloids and anthocyanin pigments in their cell sap.
The pH of plant vacuoles may be as high as 9 to 10 due to large quantities of alkaline substances or as low as 3 due to the accumulation of quantities of acids (e.g., citric, oxalic and tartaric acids).
