Cytoskeleton Overview

Flashcards covering key concepts related to cytoskeleton structure and function, including types of filaments, their roles in cellular dynamics, and the processes they are involved in.

Cytoskeleton

An interlinking network of filaments and tubules that extend throughout the cytoplasm, providing structural support and facilitating movement within the cell.

Microtubules

Cylindrical structures made up of tubulin dimers, characterized by their rigidity and dynamic instability, playing a crucial role in cell division and organization.

Actin Filaments (Microfilaments)

Thin filamentous structures composed of actin proteins, involved in various cellular processes including shape, movement, and intracellular transport.

Critical Concentration

The concentration of actin subunits at either end of a microfilament where there is neither growth nor shrinkage.

Treadmilling

A process where the addition of actin monomers to one end of a microfilament occurs at the same rate as the loss of monomers from the opposite end, resulting in a dynamic structure that maintains its length.

Persistence Length

A measure of the stiffness of a filament; for actin microfilaments, it is approximately 13.5 micrometers.

Dynamic Instability

Characteristic of microtubules where they continuously grow and shrink without reaching a steady state.

Motor Proteins

Proteins such as myosin, dynein, and kinesin that interact with the cytoskeleton to facilitate the movement of organelles and vesicles within the cell.

Intermediate Filaments

A diverse family of fibrous proteins providing mechanical strength and structural support, with no polarity and lacking associated motor proteins.

Filopodia

Thin, finger-like projections of a cell formed by actin microfilaments, involved in sensing the cellular environment and guiding movement.

Lamellipodia

Broad, sheet-like extensions of a cell composed of a dense meshwork of actin, contributing to cell migration.

Cytokinesis

The process during cell division where the cytoplasm divides to form two daughter cells, heavily reliant on the actin cytoskeleton.

Mitochondrial Transport

The movement of mitochondria along microtubules facilitated by motor proteins for energy distribution in a neuron.