The Chapter 4 Concept Check Questions are due on Monday. The Chapter 4 Test is on Monday. The T-Shirt vote will be on Tuesday. Homework: Eukaryopolis - The City of Animal Cells: Crash Course Biology #4

Chapter 4 Cell Walls and ECM

You Must Know The structure and function of the plant cell wall and the animal ECM.

Cell Walls of Plants The cell wall is an extracellular structure that distinguishes plant cells from animal cells Prokaryotes, fungi, and some protists also have cell walls The cell wall protects the plant cell, maintains its shape, and prevents excessive uptake of water Plant cell walls are made of cellulose fibers embedded in other polysaccharides and protein © 2014 Pearson Education, Inc.

Figure 4.25 Secondary cell wall Central vacuole Primary cell wall 1  m Middle lamella Plasmodesmata Cytosol Plasma membrane Plant cell walls

The Extracellular Matrix (ECM) of Animal Cells The ECM is made up of glycoproteins

Figure  m Intermediate filaments TEM 0.5  m TEM 0.1  m TEM Tight junction Tight junction Ions or small molecules Extracellular matrix Gap junction Desmosome Space between cells Plasma membranes of adjacent cells Tight junctions prevent fluid from moving across a layer of cells