The eukaryotic cytoskeleton is a highly dynamic network of filaments and motor proteins. Which of the following correctly describe activities of these cytoskeletal components? Select True or False for each statement.T/FMyosin motors walk toward the plus ends of intermediate filaments.T/FDynein motors are responsible for the whip-like movement of eukaryotic flagella.T/FKinesin motors move vesicles along tracks toward the microtubule-organizing center.T/FActin filaments are required for cytoplasmic streaming.

Verified step by step guidance

1. Understand the role of myosin motors: Myosin motors typically interact with actin filaments, not intermediate filaments. Consider the directionality of myosin movement on actin filaments.
2. Examine the function of dynein motors: Dynein motors are associated with microtubules and are known for their role in the movement of cilia and flagella. Reflect on the mechanism of flagellar movement.
3. Analyze kinesin motor activity: Kinesin motors generally move toward the plus end of microtubules, which is usually away from the microtubule-organizing center (MTOC). Consider the typical direction of vesicle transport by kinesin.
4. Consider the role of actin filaments in cytoplasmic streaming: Actin filaments, along with myosin, are involved in various cellular movements, including cytoplasmic streaming. Evaluate the necessity of actin in this process.
5. Review each statement based on the above analyses and determine whether each is true or false, considering the specific roles and directions of the motor proteins and filaments involved.

Key Concepts

Cytoskeletal Components

The cytoskeleton is composed of three main types of filaments: microtubules, actin filaments, and intermediate filaments. Microtubules provide structural support and facilitate intracellular transport, while actin filaments are involved in cell movement and shape. Intermediate filaments offer mechanical strength. Understanding these components is crucial for analyzing their respective roles and interactions in cellular activities.

Motor Proteins

Motor proteins, such as myosin, kinesin, and dynein, are essential for movement within cells. Myosin typically interacts with actin filaments to facilitate muscle contraction and cellular movement, while kinesin and dynein transport cellular cargo along microtubules in opposite directions. Recognizing the specific functions and directionalities of these motor proteins is vital for evaluating the statements in the question.

Cellular Functions of the Cytoskeleton

The cytoskeleton plays a critical role in various cellular functions, including maintaining cell shape, enabling motility, and facilitating intracellular transport. For instance, actin filaments are integral to processes like cytoplasmic streaming, which helps distribute materials within the cell. Understanding these functions helps in assessing the accuracy of the statements regarding the activities of cytoskeletal components.