Vesicles

Definition

Vesicles are small membrane-bound sacs within eukaryotic cells that transport, store, or digest cellular substances. They play a crucial role in processes such as secretion, endocytosis, and intracellular transport.

5 Must Know Facts For Your Next Test

1. Vesicles are formed by the budding off from membranes of organelles like the Golgi apparatus and endoplasmic reticulum.
2. Types of vesicles include lysosomes, transport vesicles, and secretory vesicles.
3. Lysosomes contain digestive enzymes that break down waste materials and cellular debris.
4. Transport vesicles move molecules between locations inside the cell, such as from the endoplasmic reticulum to the Golgi apparatus.
5. Secretory vesicles release their contents outside the cell via exocytosis.

Review Questions

• What is the function of lysosomes within a eukaryotic cell?
• How do transport vesicles differ from secretory vesicles in their roles?
• Describe how vesicles are formed within a cell.

Related terms

Endocytosis:

The process by which cells engulf external substances using their plasma membrane to form an internal vesicle.

Exocytosis:

The process where cells expel materials enclosed in vesicles out of the cell membrane into the extracellular space.

Golgi Apparatus: An organelle responsible for modifying, sorting, and packaging proteins and lipids for secretion or delivery to other organelles.