Chapter 6 continued Flashcards
The _______ is an extracellular structure that distinguishes plant cells from animal cells
cell wall
●Prokaryotes, fungi, and some unicellular eukaryotes also have cell walls
●The cell wall protects the plant cell, maintains its shape, and prevents excessive uptake of water
Cell Walls of Plants
Plant cell walls may have multiple layers
●Primary cell wall: Relatively thin and flexible
●Middle lamella: Thin layer between primary walls of adjacent cells
●Secondary cell wall (in some cells): Added between the plasma membrane and the primary
cell wall
_____________ are channels between adjacent plant cells
Plasmodesmata
Animal cells lack cell walls but are covered by an elaborate ____________.
extracellular matrix (ECM)
The ECM is made up of glycoproteins such as __________,___________,___________
collagen, proteoglycans, and fibronectin
ECM proteins bind to receptor proteins in the plasma membrane called _______.
integrins
Neighboring cells in tissues, organs, or organ systems often adhere, interact, and communicate through direct physical contact
Cell junctions
_____________ are channels that perforate plant cell walls
Plasmodesmata
Through _____________, water and small solutes (and sometimes proteins and RNA) can pass from cell to cell
plasmodesmata
Three types of cell junctions are common in epithelial tissues
●At tight junctions
●Desmosomes
●Gap junctions
At ___________, membranes of neighboring cells are pressed together, preventing leakage of extracellular fluid
tight junctions
