Chp. 3 Cells Flashcards
Fluid Mosaic model
Depiction of the unique structure of the cell membrane and its components
Plasma or cell membrane
Form boundary for the cell contents. Selectively permeable.
Lipid bilayer
Double layer of phospholipids with structures embedded within. Each layer of phospholipids is arranged in opposite directions
Hydrophilic regions
The polar head of each layer of phospholipids. Loves water.
Hydrophobic region
Non-polar ends of the phospholipids that meet in the center of the membrane. Water repellent to prevent water entry or loss
Membrane proteins
Embedded within or on the membrane to act as receptors, channels, carriers, etc.; make up about half the weight of the membrane; two types
Firmly embedded within the lipid bilayer. Has hydrophilic and hydrophobic regions. Receptor sites/channels
Integral proteins
Not fully embedded within the membrane. Most are attached to exposed areas of integral proteins. Can act as enzymes or attach to the cytoskeleton to maintain shape of cell
Peripheral proteins
Small finger-like projections of the cell membrane to increase the surface area of absorptive cells like small intestines or kidneys
Microvilli
Used to bind cells together to form communities of linked cells; 3 types
Membrane junctions
Proteins from adjacent membranes fuse together to form and impede able barrier; helps keep molecules from passing into the extra cellular fluid
Tight junctions
Linker proteins from adjacent cell membranes intertwine like a zipper to keep cells from pulling apart to form continuous sheet
Desmosome/anchoring junction
Forms channels between adjacent cells to allow chemicals to pass directly from one cell to another; channels formed by hollow cylinders called connexons
Gap Junction
