The cytoskeleton is a network of protein fibers that help with cellular movement and maintaining its structure/shape.
One main function of cytoskeleton is to provide mechanical support to the cell and its functions. Like the animal skeleton fix the body parts into their positions, cytoskeleton do the same for cellular organelles. The second important role cytoskeleton serves is to assist for movement. This involves both cell’s movement as a whole and trafficking of material inside the cells. In eukaryotes, there are three types of protein fibers in the cytoskeleton: microfilaments, intermediate filaments, and microtubules.
Microfilaments, which are the thinnest part of the cytoskeleton, are used for cellular movement and are used to give shape to the cell and support all of its internal parts.
As their name implies, microtubules are small hollow tubes and are the largest and widest element of the cytoskeleton. They help the cell resist compression, provide a track along which vesicles move through the cell, and pull replicated chromosomes to opposite ends of a dividing cell.
Intermediate filaments have a diameter that is between that of a microfilament and a microtubule. Intermediate filaments contribute to cellular structural elements and are often crucial in holding together tissues like skin.
Practice Questions
Khan Academy
MCAT Official Prep (AAMC)
Biology Question Pack, Vol 2. Passage 1 Question 3
Key Points
• Microfilaments are used for cellular movement and are used to give shape to the cell and support all of its internal parts.
• Microtubules help cells move material around itself and resist compression
• Intermediate filaments contribute to cellular structure and are important in holding together tissues.
Key Terms
cytoskeleton: network of protein fibers that help with cellular movement and maintaining its structure/shape
microfilaments: thin protein fibers used for cellular movement and structural maintenance
intermediate filaments: protein fibers that contribute to cellular structural elements and are often crucial in holding together tissues like skin
microtubule: small tubes made of protein that help cells move material around itself and resist compression
