Lipids Flashcards
Are the fatty acid side chains of phospholipids always unsaturated?
No, the fatty acid side chains of phospholipids can be saturated or unsaturated.
What is a key function of phospholipids in cell signaling?
Phospholipids act as precursors of intracellular signals.
How long are the fatty acid side chains of phospholipids in eukaryotic cells?
They are usually between 12 and 22 carbons long.
What property makes phospholipids suitable for forming cellular membranes?
Phospholipids are amphipathic molecules, meaning they have both hydrophilic and hydrophobic regions.
Can phospholipids be modified by intracellular enzymes?
Yes, some phospholipids are phosphorylated by intracellular protein kinases.
True or False: All fatty acid side chains of phospholipids are unsaturated.
False. Fatty acid side chains can be either saturated or unsaturated.
What causes Tay-Sachs disease?
Tay-Sachs disease is caused by the accumulation of gangliosides in lysosomes
Where does phospholipid biosynthesis occur in the cell?
Endoplasmic reticulum.
What enzyme produces phosphatidate?
The enzyme phosphatidic acid phosphatase.
What role does phosphatidylserine play in apoptosis?
Marks cells for phagocytosis
What causes respiratory distress syndrome?
Lack of phosphatidylcholine biosynthesis
Which type of lipid contains a sphingosine backbone?
Sphingolipids.
Which type of lipid includes two fatty acids joined to glycerol by ester linkages?
Phospholipids
Which type of lipid usually has branched alkyl chains?
Archaeal lipids
Which type of lipid contains one or more sugar molecules?
Glycolipids and phospholipids.
Which type of lipid is classified as a steroid?
Cholesterol
Which type of phospholipids have bent fatty acid tails?
Unsaturated phospholipids
Which type of phospholipids are built upon a glycerol backbone?
Both saturated and unsaturated phospholipids
Which type of phospholipids produce a fairly inflexible membrane at low temperatures?
Saturated phospholipids
Which type of phospholipids contain one or more double bonds within their fatty acid chains?
Unsaturated phospholipids
True or False: Both saturated and unsaturated phospholipids can be components of biological membranes.
True
What cellular lipid is a precursor of signalling molecules?
Phosphatidylinositol
Which cellular lipid is a structural component of membranes?
Phosphatidylcholine
which cellular lipid is a donor of functional groups to some membrane-anchored proteins?
Phosphatidylethanolamine
Which cellular lipid can be as much as 30% of membrane lipid, with key roles in regulating fluidity nad permeability?
Cholesterol
What is a major component of lung surfactant?
Phophatidylcholine
What is a major structural component of membranes (“lipid rafts”)?
Sphingomyelin (major sphingolipid)
