Provides strength and shape to the cell; network of protein fibers.
The correct answer and explanation is:
The correct answer is Cytoskeleton.
The cytoskeleton is a network of protein fibers that provide structural support to the cell. It helps maintain the cell’s shape, provides mechanical support, and enables cell movement. The cytoskeleton is also involved in intracellular transport and plays a critical role in cell division.
There are three main types of protein filaments in the cytoskeleton: microfilaments, intermediate filaments, and microtubules.
- Microfilaments are the thinnest fibers, composed of actin proteins. They form a dense network beneath the cell membrane, contributing to cell shape and movement. Microfilaments are also involved in processes like muscle contraction, cell division (cytokinesis), and cell motility.
- Intermediate filaments provide structural stability and strength to the cell. These fibers are thicker than microfilaments but thinner than microtubules. They are composed of various proteins, such as keratins, and help cells resist mechanical stress. In epithelial cells, for example, intermediate filaments provide resilience against stretching.
- Microtubules are hollow tubes made of tubulin proteins and are the thickest of the three types of fibers. They help maintain the cell’s shape and serve as tracks for the movement of organelles, vesicles, and chromosomes. Microtubules are essential for processes like mitosis, where they form the mitotic spindle to separate chromosomes during cell division.
The cytoskeleton is dynamic, meaning it can be reorganized as needed. It also interacts with other cell structures such as the plasma membrane, mitochondria, and the endoplasmic reticulum to coordinate the functions of the cell. By maintaining cell shape, providing support, and facilitating movement, the cytoskeleton is integral to the overall functioning of eukaryotic cells.