Mitotic spindle

Definition

The mitotic spindle is a structure composed of microtubules that segregates chromosomes into daughter cells during mitosis. It ensures accurate chromosome alignment and separation to facilitate cell division.

5 Must Know Facts For Your Next Test

1. The mitotic spindle forms during prophase and is fully developed by metaphase.
2. It consists of microtubules originating from centrosomes, also known as spindle poles.
3. The spindle fibers attach to kinetochores on the chromosomes to pull them apart.
4. Disruption in spindle formation can lead to aneuploidy, where cells have abnormal numbers of chromosomes.
5. Motor proteins like dynein and kinesin are crucial for the movement of chromosomes along the spindle.

Review Questions

• At which stage of mitosis does the mitotic spindle fully develop?
• What role do kinetochores play in relation to the mitotic spindle?
• Name two motor proteins involved in chromosome movement during mitosis.

Related terms

Microtubule: A component of the cytoskeleton involved in maintaining cell shape, intracellular transport, and cell division.

Centrosome: An organelle that serves as the main microtubule-organizing center and plays a critical role in forming the mitotic spindle.

Kinetochore:

A protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart.