Exam 3 Flashcards
Lipids are what?
Amphiphilic (hydrophilic and hyrdrophobic)
Make up 50% of membranes
What are the major lipids?
Phosphoglycerides, sphingolipids, and sterols
Sphingomyelin is derived from?
Sphingosine
The four phospholipids except sphingomyelin are derived from?
Glycerol
Cholesterol is?
A rigid planar sterol
Hydrophilic groups can?
Hydrogen bond with water but hydrophobic groups cannot
Amphiphilic molecules will spontaneously?
Form micelles or lipid bilayers in water
Caveolae are?
A lipid raft that does endocytosis
Lipid rafts are found in?
The lipid bilayer/membrane
Lipid droplets are what?
Organelles that store fatty acids in a monolayer of phospholipid
Glycolipids are assembled where?
Where are they found?
Assembled in the Golgi and delivered to membrane
Found on the non-cytosolic surface of lipid bilayers(membranes)
Membrane proteins anchor to a membrane through?
Either a fatty acid chain or a prenyl group attaching through amide linkage or thioester linkage to cysteine
Transmembrane domains contain?
Mainly non polar amino acids
Transmembrane proteins often contain?
Intrachain disulfide bonds and can be glycosylated
Glycocalyx are used for?
Cell recognition purposes
What can stain the membrane?
Carbohydrate binding proteins called lectins or ruthenium red
Spectrin does what?
Provides membrane with shape and structural integrity
Which of the following lipids has a net negative charge at physiological pH?
Phosphatidylserine
What is the carbohydrate layer on the outer surface of cells called?
Glycocalyx
What type of cell:cell junction would you expect to find at the basal plasma membrane of epithelial cells, connecting them to the basal lamina?
Hemidesmosomes
Artificial phospholipid bilayer vesicle formed from an aqueous suspension of phospholipid molecules
Liposome
Small region of the plasma membrane enriched in sphingolipids cholesterol
Lipid raft
Any glycolipid having one or more sialic acid residues in its structure; especially abundant in the plasma membranes of nerve cells
Ganglioside
Having both hydrophobic and hydrophilic regions, as in a phospholipid or a detergent molecule
Amphiphilic
The main type of phospholipid in animal cell membranes, with two fatty acids and a polar head group attached to a three carbon glycerol backbone
Phosphoglyceride
Lipid molecule with a characteristic four ring steroid structure that is an important component of the plasma membranes of animal cells
Cholesterol
Protein that binds tightly to a specific sugar
Lectin
The outer coat of a eukaryotic cell, composed of oligosaccharides linked to intrinsic plasma membrane glycoproteins and glycolipids, as well as proteins that have been secreted and reabsorbed onto the cell surface
Carbohydrate layer
Abundant protein associated with the cytosolic side of the plasma membrane in red blood cells, forming a rigid network that supports the membrane
Spectrin
Protein whose polypeptide chain crosses the lipid bilayer more than once
Multipass transmembrane protein
Pigmented protein found in the plasma membrane of Halobacterium halobium, where it pumps protons out of the cell in response to light
Bacteriorhodopsin
The complicated cytoskeletal network in the cytosol just beneath the plasma membrane
Cortex
Type of lipid linkage, formed as proteins pass through the endoplasmic reticulum, by which some proteins are attached to the noncytosolic surface of the membrane
Glycosylphosphatidylinositol anchor
An aqueous pore in a lipid membrane, with walls made of protein, through which selected ions or molecules can pass
Channel