BIO - TERMS - LIPID Flashcards
bilayer
A double layer of oriented amphipathic lipid molecules, forming the basic structure of biological membranes. The hydrocarbon tails face inward to form a continuous nonpolar phase.
bile salts
Amphipathic steroid derivatives with detergent properties, participating in digestion and absorption of lipids.
Biomembrane
Permeation barrier around every cell or cellular compartments consisting of phospholipids, cholesterol, and membrane proteins. The integrity of its biomembrane is a requisite for any cell.
carbohydrate layer
The carbohydrate-rich zone on the eukaryotic cell surface attributable to glycoproteins, glycolipids, and proteoglycans of the plasma membrane.
caveola (plural caveolae)
Invaginations at the cell surface that bud off internally to form pinocytic vesicles. Thought to form from lipid rafts, regions of membrane rich in certain lipids.
Caveolae
Flask-shaped invaginations of the plasma membrane of many types of cells that contain the protein caveolin and are rich in lipid rafts; caveolae internalize membrane components, extracellular ligands, bacterial toxins, and some animal viruses. (Chapter 5)
cell membrane structure
The outer portion of a cell, composed of lipid and protein.
Ceramide
A lipid consisting of sphingosine and a fatty acid.
cis Golgi network (CGN)
Network of fused vesicular tubular clusters that is closely associated with the cis face of the Golgi apparatus and is the compartment at which proteins and lipids enter the Golgi.
de novo lipogenesis
The synthesis of complex lipids from simple compounds.
dolichol
Isoprenoid lipid molecule that anchors the precursor oligosaccharide in the endoplasmic reticulum membrane during protein glycosylation.
Dolichol phosphate
A lipid that participates in the synthesis of N-linked oligosaccharides in glycoproteins.
ether linkage
Bonding between fatty acids and glycerol in archaeal phospholipids: @@@@C¬O¬C@@@@@
Fusion pore
An opening between two lipid bilayers formed by the action of fusion proteins; it allows exchange of material across membranes. (Chapter 5)
Gaucher disease
A lipid storage disease in which glucocerebroside accumulates.
glycosphingolipid
An amphipathic lipid with a sphingosine backbone to which are attached a long-chain fatty acid and a polar alcohol.
glycosylphosphatidylinositol (GPI) tail
A glycolipid modification of proteins that can allow attachment to host membranes without the requirement of a transmembrane protein domain.
glycosylphosphatidylinositol anchor (GPI anchor)
Lipid linkage by which some membrane proteins are bound to the membrane. The protein is joined, via an oligosaccharide linker, to a phosphatidylinositol anchor during its travel through the endoplasmic reticulum.
Hyperlipidemia
Too much lipid in the blood.
inositol phospholipid signaling pathway
Intracellular signaling pathway that starts with the activation of phospholipase C and the generation of IP3 and diacylglycerol (DAG) from inositol phospholipids in the plasma membrane. The DAG helps to activate protein kinase C.
intraluminal phase
The digestion of lipids within the lumen of the gastrointestinal tract (mainly the small intestine). intrinsic pathway In blood clotting, the process by which prothrombin is activated via the interaction of factor XII with collagen fibers of a damaged blood vessel. Sometimes referred to as the contact activation pathway or tissue factor pathway.
lacteal
(lak′tē-al) Lymphatic capillary where lipids and lipidsoluble vitamins are absorbed from the small intestine.
lamellar bodies
Lipid-rich secretory organelles in keratinocytes and lung pneumocytes that release β-defensins into the extracellular space.
lipidome
The full complement of lipidcontaining molecules in a cell, organ, or tissue under a particular set of conditions.
lipidomics
The systematic characterization of the lipidome.
lipid A
A component of the gram-negative outer membrane; endotoxin.
lipid droplets
Storage form in cells for excess lipids; comprised of a single monolayer of phospholipids and proteins that surrounds neutral lipids that can be retrieved from droplets as required by the cell.
lipopeptide antigens
A diverse set of antigens derived from microbial lipids typically presented by nonclassical MHC class Ib molecules such as CD1 molecules to invariant T-cell populations, including iNKT cells.
liver X receptor (LXR)
A nuclear receptor that binds to gene promoters that up-regulate transporters for cholesterol transfer to HDL-cholesterol, transporters that regulate cholesterol absorption, and transporters that facilitate cholesterol and phospholipid export from the liver.
Lung surfactant
A lipid secretion that reduces the surface tension in the lung alveoli.
Malondialdehyde
A chemically reactive product formed during lipid peroxidation.
Membrane
A macromolecular structure composed of lipids and proteins that surrounds a cell or certain of the organelles within a cell, such as the mitochondria and chloroplasts; also, a component of the endoplasmic reticulum within cells.
microbial glycolipids
Diverse class of antigens frequently presented by CD1 molecules to iNKT cells.
Microdomain
Regions of the plasma membrane with distinct lipid and protein composition. (Chapter 2)
Monoterpenoids
Ten-carbon lipids.
mucosal phase
The digestion of lipid breakdown products within the mucosal cells of the small intestine. The synthesis of medium-chain triglycerides and the re- esterification of cholesterol occurs in this phase.
myo- i nositol
Component of phosphatidylinositol; prevents diet-induced lipodystrophies due to impaired lipid transport in gerbils and rats; essential for some microbes, gerbils, and certain fishes
phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2, PIP2]
Membrane inositol phospholipid (a phosphoinositide) that is cleaved by phospholipase C into IP3 and diacylglycerol at the beginning of the inositol phospholipid signaling pathway. It can also be phosphorylated by PI 3-kinase to produce PIP3 docking sites for signaling proteins in the PI-3-kinase–Akt signaling pathway.
phosphoinositide
A lipid containing a phosphorylated inositol derivative. Minor component of the plasma membrane, but important in demarking different membranes and for intracellular signal transduction in eukaryotic cells.
Phosphoinositide 3-kinase
A lipid kinase that mediates effects of growth factors and insulin.
phospholipid bilayer
The arrangement of phospholipid molecules that forms the basic structure of the cell membrane. The core of the bilayer is lipid, creating a barrier to water and to water-soluble ions and molecules.
phosphoinositides (PIPs; phosphatidylinositol phosphates)
A lipid containing a phosphorylated inositol derivative. Minor component of the plasma membrane, but important in demarking different membranes and for intracellular signal transduction in eukaryotic cells.
PIP2
Phosphatidylinositol 3,4-bisphosphate, a membrane-associated phospholipid that is cleaved by phospholipase C-γ to give the signaling molecules diacylglycerol and inositol trisphosphate and is phosphorylated by PI3-kinase to generate PIP3.
PIP3
Phosphatidylinositol 3,4,5-trisphosphate, a membrane-associated phospholipid that can recruit intracellular signaling molecules containing pleckstrin homology (PH) domains to the membrane.
PTEN
A lipid phosphatase that hydrolyzes 3-phosphorylated phosphoinositides; the product of an important tumor suppressor gene.
Rhamnolipids
A class of glycolipids produced by Pseudomonas aeruginosa frequently cited as the best characterized of the bacterial surfactants They have a glycosyl head group, in this case a rhamnose moiety and a 3-(hydroxyalkanoyloxy)-alkanoic acid (HAA) fatty acid tail.
secretory phase
The phase of lipid digestion in which lipid products are expelled into the lymph or portal vein.
Sesquiterpenoids
15-carbon lipids.
Sphingolipidosis
Lipid storage disease; a type of disease caused by the deficiency of a sphingolipid-degrading lysosomal enzyme.
sphingosine 1-phosphate (S1P)
A phospholipid with chemotactic activity that controls the egress of T cells from lymph nodes.
Xanthoma
Visible subcutaneous lipid deposit.
α-galactoceramide (α-GalCer)
An immunogenic glycolipid originally extracted from marine sponges but actually produced by various bacteria that is a ligand presented by CD1 to invariant NKT (iNKT) cells.
α-Tocopherol
The most active form of vitamin E; an important lipid-soluble antioxidant.
diterpene
A class of terpenoids found in plants that have antibacterial, antiviral, antifungal properties. digestible indispensable amino acid score (DIAAS) A numerical term to compare relative protein quality with the level of essential amino acids present in a food.
limonene
A monoterpene found in citrus peels that is thought to relieve gastroesophageal reflux disease and heartburn. May detoxify certain cancer-causing compounds by increasing the activity of liver enzymes.
limonoid
A triterpene found in citrus fruits that imparts a bitter flavor. It is thought to have anticancer, antifungal, antibacterial, and antimalarial properties.
menthol
A monoterpene found in peppermint oil that can create a cooling sensation when it comes into contact with skin or mucus membranes.
monoterpene
A plant-based essential oil found in fruits, vegetables, and herbs. Can prevent initiation and progression of cancer and can also be used as a cancer treatment.
sesquiterpene
A class of plant-based essential oils similar to monoterpenes; have antiseptic and antiinflam matory properties.
Sesquiterpene lactone
Terpene with 15 C atoms; its exocyclic methylene group can bind to SH-groups of proteins or glutathione.
tetraterpenoid
A class of compounds that have 8 isoprene molecules (or 4 monoterpene molecules) and 40 carbons. Carotenoids are a type of tetraterpenoid.
triterpene
Precursors to plant sterols that contain six isoprene rings.
diuretic
(dı̄-ū-ret′ik) Agent that increases the excretion of urine.
Iridoids
A subgroup of monoterpenoids with iridoid glucosides, secoiridoids, and secologanin.
isoprene
The hydrocarbon 2-methyl- 1,3-butadiene, a recurring structural unit of terpenoids.
Isoprene rule
An observation to the effect that terpenoids appear to be made up of isoprene (2-methyl-1,3-butadiene) units connected head-to-tail.
Limulus amebocyte lysate (LAL) assay
A test to detect the presence of bacterial endotoxins.
line of pull
Median direction of contraction of the main muscles involved in the technical skill.
merozoite
A trophozoite of Plasmodium found in red blood cells or liver cells.
Monounsaturated fatty acid
Fatty acid with one carbon-carbon double bond.
sex-determining region of the Y chromosome (SRY)
A gene on the Y chromosome that codes for testis-determining factor; essential for normal male development.
Sex-influenced dominance
A dominant expression that depends on the sex of the individual. For example, horns in some breeds of sheep are dominant in males and recessive in females.
thermal death point (TDP)
The temperature required to kill all the bacteria in a liquid culture in 10 minutes.
trophozoite
The vegetative form of a protozoan.
