2e Flashcards
What are the main extracellular structures synthesized by cells?
Cell walls of plants, extracellular matrix (ECM) of animal cells, and intercellular junctions.
What is the function of the plant cell wall?
Protects the cell, maintains shape, and prevents excessive water uptake.
Describe the composition of plant cell walls.
Made of cellulose fibers embedded in polysaccharides and proteins.
What are the layers of the plant cell wall?
Primary cell wall, middle lamella, and secondary cell wall.
What are plasmodesmata?
Membrane-lined pores connecting adjacent plant cells for communication and transport.
What is the role of the extracellular matrix (ECM) in animal cells?
Provides support, adhesion, movement, and regulation.
What are the types of intercellular junctions in animal cells?
Tight junctions, desmosomes, and gap junctions.
How do tight junctions function?
They prevent fluid from moving across a layer of cells.
What is the function of gap junctions?
Provide cytoplasmic channels for communication between animal cells.
How do desmosomes contribute to tissue structure?
They anchor cells together into strong sheets.
