Centrosome and Centrioles Flashcards
What is the centrosome?
The centrosome is a small region of cytoplasm that produces microtubules. In animal cells, it contains two small structures called centrioles.
What are centrioles?
Centrioles are cylinder-shaped organelles made of short microtubules arranged in a circle. The two centrioles are perpendicular to each other.
What happens before an animal cell divides?
Before an animal cell divides, the centrosome, including the centrioles, doubles and the two new centrosomes move to opposite ends of the cell.
What are microtubules?
Microtubules are a component of the cytoskeleton, found throughout the cytoplasm. They grow from each centrosome, forming spindle fibers.
What do these fibers do?
Thers fibers attach to the DNA and appear to help divide it between the two cells.
What is special about centrioles?
Animal cells can divide even of the centrioles are removed. In addition, centrioles are found in some algae, but they are not found in plants.
What other function have centrioles?
Centrioles also organize microtubules to form cilia and flagella. Cilia look like little hairs and flagella look like a whip or a tail.
What is special about cilia and flagella?
Their motion forces liquids past a cell. For single cells, this movement results in swimming. For cells anchored in tissue, this motion sweeps liquid across the cell surface.
REMEMBER!
Centrioles divide DNA during cell division!
