Chapter 11- Membrane Structure Flashcards
cell membranes consist of a _____ double layer, or a ____ of lipid molecules
continuous, bilayer
the ____ ____ provides the basic structure and barrier function of all cell membranes
lipid bilayer
Membrane lipid molecules are ___, meaning they have both hydrophobic and hydrophilic regions
amphipathic
three major classes of membrane lipid molecules
phospholipids, sterols, glycolipids
the lipid bilayer is ____, and individual lipid molecules are able to ___ within their own monolayer
fluid, diffuse
cells that live at different temperatures maintain their membrane fluidity by modifying their ___ ____ of their membranes
lipid composition
Membrane proteins are responsible for most functions of membranes including, ___ of small, ___-___ molecules across the lipid bilayer
transport, water-soluble
______ proteins extend across the lipid bilayer usually as one or more alpha helices, but sometimes as a ___ sheet rolled into the form of a barrel
Transmembrane, beta
Other membrane proteins do not extend across the lipid bilayer but are ___ to ___ or ___ side of the membrane
attached, one, another
most cell membranes are supported by an attached ____ of ____
framework, proteins
many of the proteins and some of the lipids exposed on the surface of the cell have attached ___ __
suagr chains
the ____ ____ helps protect and lubricate the cell surface, while also being recognized in cell to cell recongition
carbohydrate layer
specialized layer of cytoplasm on the inner face of the plasma membrane. In animal cells, it is rich in actin filaments that govern cell shape and drive cell movement
cell cortex
this short rigid lipid molecule, found in large amounts in the membrane, makes the lipid bilayer less flexible
cholesterol
soapy substance used to solubilize membrane proteins
detergent
protective layer of carbohydrates on the outside surface of the plasma membrane formed by sugar residues of membrane glycoproteins, proteoglycans, and glycolipids
glycocalyx
functionally and specialized region in the membrane of a cell or organelle; typically characterized by the presence of specific proteins
membrane domain
organic molecule that contains a full complement of hydrogen, aka no double bonds
saturated
organic molecule that contains one or more double bonds or triple bonds between its carbon molecules…. creates a kink
unsaturated
structure of cell membranes is determined by the way the membrane lipids behave in an ____ environment
aqueous
the molecules of a bilayer are able to ____ ____ to eliminate a free edge if a tear is made
spontaneously rearrange
the ___ and more ___ the packing of phospholipid tails, the more viscous and less fluid the bilayer will be
closely, regular
the two major properties of hydrocarbon tails that affect how tightly they pack in the bilayer are ___ & ____
length, number of double bonds they contain
lipid bilayers that contain a larger proportion of unsaturated hydrocarbon tails are more ___ than those with lower proportions
fluid
