Plasma membrane, Cell wall, cellular junction

Plasama membrane

• Boundary around all cells

• Selectively- permeable

Components

• Lipids (phospholipids and cholesterol)

• Proteins

Extracellualr matrix

• Located on the outside of all animal cells

Components-

• Collagen

• glycoproteins and glycolipids

Function- cell adhesion, cell recognition, cell communication

Cell Wall

• Non- living “jacket” around some cells

• Plants (cellulose)

• fungi (Chitin)

• bacteria (prokaryotes)

• some protists (algae)

Plasmodesmata 

Plants

• Channels that connect the plant cell walls

• Allows for communication 

Tight Junctions

Animals

• Seals of cavities

• Prevents the movement of materials between cells

Anchor

• do not seal of cavities- materials can pass through

• threads of keratin anchoring the cells together

• allow for flexibility/stretching- bladder, stomach

Gap

• Channels

• allow for movement of ionst signals between cells

• heart + smooth muscle