Cells In Their Environment Flashcards
What are the main components of the cytoskeleton?
Actin filaments (microfilaments), intermediate filaments, and microtubules.
What are the functions of actin filaments in cells?
They determine cell shape, aid in movement, support muscle contraction, and are essential in cell division.
What role do microtubules play in the cell?
Microtubules position organelles, support cell structure, and are crucial for cell division as part of the mitotic spindle.
How do cells move through the extracellular matrix (ECM)?
Cells use actin polymerization to push the membrane forward and integrins to attach to the ECM, with motor proteins pulling the cell along.
What is the extracellular matrix (ECM)?
A complex network that provides structural support, biochemical cues, and mechanical strength to cells and tissues.
What are the major components of the ECM?
Collagen, proteoglycans, and fibronectin.
What function do integrins serve in cell-ECM interactions?
Integrins act as matrix receptors, connecting cells to the ECM and allowing signal transmission between the cell and its environment.
How do tight junctions contribute to cell organization in tissues?
They create impermeable barriers between cells, maintaining tissue integrity and selective permeability, as seen in the blood-brain barrier.
What is the function of gap junctions?
Gap junctions are channels formed by connexin proteins that allow small molecules and signals to pass between cells, facilitating communication and coordination.
What is the role of desmosomes in tissues?
Desmosomes provide mechanical strength by linking cells via intermediate filaments, especially in tissues subject to stress, like skin and cardiac muscle.
What are focal adhesions?
Structures where integrins connect the cell cytoskeleton to the ECM, crucial for cell adhesion, movement, and signaling.
Describe the movement outside the ECM
The cytoskeleton has a role in cell movement through flagella and cilia
Enable movement of cells such as bacteria or sperm
