Chap 6 Flashcards
Biological membrane
Separate cells from its external environment or creates intercellular components
Phospholipid heads
A phosphate group and glycerol
Negativity charged
Polar
Hydrophilic
Face outward the aqueous
Phospholipid tails
Two fatty acid chains
Uncharged
Nonpolar
Hydrophobic
Face inward towards each other
Biological membrane
Have a cell structure however membrane s of specific cells and organelle differ in the kinds of proteins and lipids
Glycolipids
Carbs+lipids
Less diverse group
Facilitate cell recognition
Glycoproteins
More diverse group
Serve as receptors for chemical signals
Cell arrangements
Cell arrangements themselves in tissues by two process
Cell recognition: one cell type specifically recognizes
Cell adhesion ; connections between two cell is strengthened
Cell junction
Specialized structures associated with the plasma membrane
Tight junction prevent substances from moving through the space between the cell
Gab junction
Channels run between membranes pores in adjacent
6.2 cell membrane is important in cell adhesion and recognition
Cell membrane also adhere to the extra cellular matrix
The transmembrane protein integrin binds to the matrix outside
The biding is noncovalent and reversible
6.4 active transport
Active transport moves substance against a concentration
The energy sources is often adenosine triphosphate
Primary active transport
Requires direct hydrolysis of atp
Secondary active transport
Energy cones from an ion concentration gradient
6.5. Large molecules
Endocytosis brings molecule and cell into a eukaryotic cell
Three types of endocytosis
Phagocytosis molecules or entire cells are engulfed
Pinocytosis a vesicle forms to bring small dissolved substances or fluids in cell
Receptor mediated macromolecules to be bind to receptor proteins integral membrane proteins located at specific sites on the cell membrane
