Membrane lipids are _____ molecules meaning the have both a hydrophobic and hydrophilic end
amphipathic
the membrane ______ are embedded in the layer and perform most of the other functions of the membrane.
proteins
3 classes of membrane lipids
1) _______(majority)
2)________
3)________
phospholipids
cholesterol
glycolipids
Is the phospholipid tail is a kink, this kink occurs becuase of a _______ _______
cis-double bond
4 major types of phospholipids include;
1)
2)
3)
4)
phosphatidyl-ethanlamine
phosphatidyl-serine (has negative charge/ on cytosol side of the membrane)
phosphatidyl-choline
sphingomyelin
The is the only type of cell with no cholesterol in their cell compostion
bacteria cell
Some eukaryotic membrane lipids are _______ with oligosaccharides on the _________ side of the membrane
glycosylated
noncytosolic
This molecule is ampipathic, contains a polar head (-OH), and contains a steroid ring structure
cholesterol molecule
Cholesterol ________ the ability of the lipid bilayer to act as a ________ barrier to small _______ substances
increases
permeability
water-soluble
True/false(make true) : lipids can only pack into the bilayer method as in membranes.
false: can form sperical molecules (a lipid Micelle) as well as a lipid bilayer
True/False (make true): Spontaneous aggregation to spherical shape is energetically favorable
true. Tears in layer are repaired due to spontaneous aggregation
Lipids move freely in the bilayer: Name the most and least common movements of the 4 possible.
MOST: Lateral diffusion (within monolayer) --- from inherit kenetic energy
LEAST: flip-flop (rare due to lipids great fluidity)
Fibroblasts can accumulate fat droplets and transform the cell into a ______
adipocyte
True/false (make true): the lipid bilayer is symmetrical
false. The lipid bilayer is NOT symetrical. Proteins free float and can clump anywhere in the layer where required for protein functions. Cholesterol is distributed equally
The type of phospholipid faces the cytosol and has a negative charge
phospatidyl-serines
Glycolipids face the ________ leaflet
non-cytosolic
the molecules perform the specific functions of the plasma membrane
membrane proteins
MOST membrane proteins are _________________ (added oligosaccharide); termed a ________
glycolsylated
glycoprotein
This part of the membrane on the ________ side is known as a glycocalyx
The carbohydrate layer
noncytosolic
Which side of the membrane contains NO oligosaccharides on the molecules
cytosol side
the carbohydrate layer funtions for 2 ;
1)
2)
provides protection
role in cell to cell interactions
_____ _____ between the apical plasma membrane (lumen of small intestine) and lateral plasma membrane restrict lateral diffusions of lateral ______
tight junctions
proteins
There are _ mechanisms that restrict lateral diffusion of proteins. These restrictions function to _______________________________________________