Biochemistry 1430- Chapter 29 || Well-Enlightened

The starting materials necessary to synthesize sphingosine are: correct answers palmitoyl CoA and serine Which of the following is(are) major component(s) of low-density lipoproteins? correct answers A) phospholipid B) apoprotein B-100 C) cholesteryl ester D) All of the above <<<<<<< E) None of the above In a ganglioside, what links the oligosaccharide to the hydroxyl of the ceramide? correct answers Glucose The LDL receptors on the plasma membrane are localized in coated pits that contain the receptors of which of the following proteins? correct answers Clathrin A friend, who is struggling with weight gain, reads about a new miracle supplement that blocks the formation of phosphatidate, the precursor for triacylglycerols. Would taking this supplement work as a weight reduction scheme? correct answers No, because this would also block formation of phospholipids and cell membrane integrity would be impacted. Hydroxylation of cholesterol by cytochrome P450 requires: correct answers NADPH and activated O2 Tay Sachs disease is caused by an inability to degrade: correct answers gangliosides Feedback regulation of cholesterol synthesis is mainly controlled at the step catalyzed by the enzyme: correct answers 3-hydroxy-3-methylglutaryl (HMG) CoA reductase. Phosphatidate is formed from: correct answers glycerol 3-phosphate and two fatty acyl CoAs. In previous chapters, biosynthetic pathways were commonly regulated by phosphorylation/ dephosphorylation mechanisms. Which of the following mechanisms for steroid biosynthesis uses an alternative method? correct answers The sterol regulatory element binding protein (SREBP) migrates to the nucleus and binds the sterol regulatory element (SRE) stimulating transcription. The role of lipoprotein particles is to: correct answers solubilize hydrophobic lipids and contain cell-targeting signals You are prone to sunburn, but your doctor tells you not to apply your sunscreen until you have been outside for five minutes. Why? correct answers Sunlight is necessary for the conversion of cholesterol to vitamin D, a hormone necessary for bone health.