Question

An elaborate network of filamentous proteinaceous structures present in the cytoplasm is collectively known as (a) Cilia (b) Flagella (c) Cytoskeleton (d) ER

Short answer

The correct answer is (c) Cytoskeleton.

Step-by-step solution

Understand the function of given terms

In this step, having a brief understanding of each option is important. (a) Cilia are small hair-like structures on the cell surface used for locomotion or moving substances over the cell surface. (b) Flagella are long whip-like structures used for cell movement. (c) Cytoskeleton is a network of protein filaments and tubules in the cytoplasm, providing shape and facilitating cell movement and division. (d) ER, or endoplasmic reticulum, is involved in protein and lipid synthesis.

Match the given description with the correct term

The question describes 'an elaborate network of filamentous proteinaceous structures present in the cytoplasm'. The term that matches this description is the cytoskeleton, as it is a network of protein filaments within the cytoplasm.

Key concepts

Protein Filaments in Cells

The term 'cytoskeleton' might evoke an image of a stable, rigid framework, akin to the bones in our body. However, this cellular skeleton is anything but static. It's a dynamic system comprising different types of protein filaments, crucial for maintaining cell shape, enabling intracellular transport, and ensuring cells can move and divide.

Inside every eukaryotic cell, the cytoskeleton consists of three primary types of filaments: microfilaments, intermediate filaments, and microtubules. Microfilaments, also known as actin filaments, are the thinnest type and are pivotal for muscle contraction, cell division, and cell motility. Intermediate filaments provide mechanical support for the plasma membrane where it comes into contact with other cells or with the extracellular matrix. Lastly, microtubules are the thickest filaments and they play key roles in maintaining cell shape, forming the spindle during cell division, and serving as tracks for the movement of organelles and vesicles.

Cell Structure and Organization

Diving into the realm of cell biology, we find that structure and organization are paramount. A cell's intricacies can be understood when we consider how its components are arranged to perform life-sustaining functions. At the heart of this organization is the cytoskeleton, which acts like the scaffoldings of a building, providing support and determining the cell's structure.

The cytoskeleton's filaments crisscross the cytoplasm, creating a network that organizes the cell's contents and anchors organelles in place. This organization is not fixed; it dynamically changes to accommodate cell movement, growth, and division. Furthermore, the cytoskeleton's interactions with other cellular components, such as the endoplasmic reticulum and the plasma membrane, help to maintain the distinct compartments within the cell, crucial for the integrity and functionality of various biological processes.

Cell Movement and Division

Without the cytoskeleton, cells would not only lack shape, but they would also be immobilized and unable to reproduce. The cytoskeleton is central to cell motility, seen in processes ranging from the simple crawling of single-celled organisms to the intricate migration of cells during embryonic development. Cells move by extending their cytoskeleton and adhering to surfaces before pulling the rest of their body forward—a process known as amoeboid movement.

Similarly, cell division is a complex dance choreographed by the cytoskeleton's filaments. During mitosis, microtubules form a structure called the mitotic spindle, which segregates chromosomes into two new cells, ensuring genetic material is accurately and equally divided. Without these protein filaments, cells could neither maneuver through their environments nor reliably replicate, eliminating the possibility for growth and repair in multicellular organisms.