Animal cell surface Flashcards
Cell adhesion molecules
Bind cells together
Cell junctions
Seal spaces between cells and provide communications
Extracellular matrix
Support and protect cells and provide mechanical linkages
Cell adhesion molecules details
Glycoproteins embedded in the plasma membrane. Help maintain body form and structure by binding to molecules and other cells
Cell adhesions is utero
Initial connections are formed and then break and reform as the embryo grows
Cell adhesions adults
The connections become permanent
Cancer adhesions
Can break allowing the tumor to spread around the body
Bacteria and virus’ target
Cell adhesion sites for sites of infection
Organ rejection
Is a immune response due to foreign cells surface molecules
3 types of junctions
Anchoring, tight and gap
Anchoring junction
Button or belt like spots are created to weld cells together
Desmosomes
Intermediate filaments anchor the junction in the cytoplasm
Adheres junction example
Heart, muscles, skin
Adheres junction
Microfilaments anchor to the cytoskeleton, commonly seen in stretchy or shear cells
Tight junctions
Tight connections. Can prevents ions from coming between. Seal the spaces between cells
Tight junction examples
Outer surface of the body, lining of internal cavities, the stomach
Creation of tight juncitons
Proteins on the outer surface of the plasma membrane fuse. Appears like stitch work.
Gap junctions
Open channels that allow ions/small molecules to pass cell to cell. Protein cylinders line up to create a pipeline connecting cytoplasms
Gap junctions adavantage
They allow for immediate communication
Gap junctions in vertabrets
Almost all body tissue. Heart, uterus, and dental pulp. Allows for organs to coordinate
Extracellular matrix
Made of proteins and polysaccharides. Many cells are imbedded in it
Primary function of the Extracellular matrix
Protection and support
Other functions of the Extracellular matrix
Forms masses of skin, bone, tendon, cornea, kidney, cell division, embryonic development, reaction to wounds and disease
Glycoproteins
Main component of the Extracellular matrix
Collagen
The most abundant glycoprotein in animals. Strong and elastic. Makes up 1/2 of protein by mass in vertebrates
Extracellular matrix consistancy
Can be soft and jelly like or and elastic.
Extracellular matrix texture depends on
the number of interlinks which determines the amount of trapped oxygen
Proteoglycans
Glycoproteins made up of small proteins non covalently bonded to polysaccharide molecules
Fibronectins
A glycoprotein that organizes Extracellular matrix and allow cells to bond to their receptor proteins called integrins.
Integrins
Cover the plasma membrane
Integrins on the cytoplasm side
Bind to microfilaments of the cytoskeleton and make change to the cell by communicating to the cytoskeleton
