vacuole

Examples of vacuole in the following topics:

• Vacuoles

• Vesicles and Vacuoles

  • Vesicles and vacuoles are membrane-bound sacs that function in storage and transport.
  • The membrane of a vacuole does not fuse with the membranes of other cellular components.
  • Vacuoles are an essential component of plant cells.
  • As the central vacuole shrinks, it leaves the cell wall unsupported.
  • The central vacuole also supports the expansion of the cell.

• Contractile Vacuoles in Microorganisms

  • Contractile vacuoles absorb excess water and wastes from a microorganism's cell and excrete them into the environment by contracting.
  • Previously, a CV was known as a pulsatile or pulsating vacuole.
  • CVs should not be confused with vacuoles which store food or water.
  • After the canals fill with water, it is pumped into the vacuole.
  • When the vacuole is full, it expels the water through a pore in the cytoplasm that can be opened and closed.

• Comparing Plant and Animal Cells

  • Plant cells have a cell wall, chloroplasts and other specialized plastids, and a large central vacuole, whereas animal cells do not.
  • In plant cells, the digestive processes take place in vacuoles.
  • The central vacuole plays a key role in regulating the cell's concentration of water in changing environmental conditions.
  • As the central vacuole shrinks, it leaves the cell wall unsupported.
  • The central vacuole also supports the expansion of the cell.

• Characteristics of Eukaryotic Cells

  • Vesicles and vacuoles are membrane-bound sacs that function in storage and transport.
  • Other than the fact that vacuoles are somewhat larger than vesicles, there is a very subtle distinction between them: the membranes of vesicles can fuse with either the plasma membrane or other membrane systems within the cell.
  • In addition, plant cells have a cell wall, a large central vacuole, chloroplasts, and other specialized plastids, whereas animal cells do not.
  • The cell wall protects the cell, provides structural support, and gives shape to the cell while the central vacuole plays a key role in regulating the cell's concentration of water in changing environmental conditions.
  • Plant cells have a cell wall, chloroplasts, plasmodesmata, and plastids used for storage, and a large central vacuole, whereas animal cells do not.

• Chromalveolata: Alveolates

  • The apicomplexan protists are so named because their microtubules, fibrin, and vacuoles are asymmetrically distributed at one end of the cell in a structure called an apical complex .
  • Food captured in the oral groove enters a food vacuole where it combines with digestive enzymes.
  • In addition to a vacuole-based digestive system, Paramecium also uses contractile vacuoles: osmoregulatory vesicles that fill with water as it enters the cell by osmosis and then contract to squeeze water from the cell.
  • Contractile vacuoles allow the organism to excrete excess water.

• Ovarian Cysts

  • An ovarian cyst is a fluid-filled vacuole within or on an ovary.

• Overview of the Endocrine System

  • Endocrine glands are typically well vascularized and the cells comprising the tissue are typically rich in intracellular vacuoles or granules that store hormones prior to release.

• Osmoregulation

  • For example, paramecia and amoebas, which are protists that lack cell walls, have contractile vacuoles.
  • A paramecium's contractile vacuole, here visualized using bright field light microscopy at 480x magnification, continuously pumps water out of the organism's body to keep it from bursting in a hypotonic medium.

• Sea Coral and Sea Anemone Zooxanthellae

  • The vacuole structure containing the symbiont is therefore termed the symbiosome, and only a single symbiont cell is found within each symbiosome.