An unknown sample known to contain either triglycerides or phospholipids is placed in water. The sample forms a separate layer o
n top of the water, with no mixing in the bulk volume of water. What type of lipid does the sample contain, and what structural element is responsible for the sample’s behavior in water? a. Triglycerides, double bonds in fatty acid tails b. Triglycerides, ester linkages c. Triglycerides, long-chain hydrocarbon tails d. Phospholipids, ester linkages e. Phospholipids, glycerol backbone
Answer: Option C) Triglycerides, long-chain hydrocarbon tails
Explanation:
Triglycerides are lipids, with three fatty acids (the same or different) having long hydrocarbon tails.
The hydrocarbon tails in triglycerides is the structural element that makes it insoluble in water as seen in the sample forming a separate layer on top of the water because it does not form hydrogen bonds with water molecules i.e hydrophobic
Unlike a bar magnet<span>, however, </span>Earth's magnetic field<span> changes over time because it is generated by a geodynamo (in </span>Earth's<span> case, the motion of molten iron alloys in its outer core).</span>
The main enzyme responsible for RNA synthesis is RNA polymerase, which <em>catalyzes the polymerization of 5'-triphosphate ribonucleosides (NTP) </em>directed by a DNA mold.
Eukaryotic cells contain <u>three types of nuclear RNA polymerases</u> that transcribe different types of genes. Protein-encoding genes are transcribed by RNA polymerase II to give mRNA.
<span>The commonly accepted values is 4 Calories per gram of protein and carbohydrate and 9 Calories per gram of fat. Since we have 2 grams of each, a little simple math will do:
2 g * 4 Cal/g + 2 g * 4 Cal/g + 2 g *9 Cal/g = 8 Cal + 8 Cal + 18 Cal = 34 Cal</span>
