Biochemistry Lipids Quiz

Glycerol is a very simple 3 carbon molecule. Each carbon carries a hydroxyl functional group. (OH)

The carboxyl group at one end (red) and the bent shape of the molecule, indicatin a double or triple Carbon bond, make this an unaturated fatty acid.

Only the lower molecule shows any double bonds; it is unsaturated - specifically, because it has two C=C double bonds, it is a polyunsaturated fat.

Please don't tell me you picked antipasto. Unless you're hungry.

The breaking (lysis) of a molecule using water (hydro) is hydrolysis.

Vertebrates store lipids for future nutritional energy, and even as insulation & protection of internal organs. Lipids make up all eukaryotic cell membranes. Steroid hormones are of lipid origin. Only starches produce glucose when digested.

Phospholipids arranged in a bilayer are the basis of all cell membranes.

The molecule only exhibits single bonds between carbons (C-C)

The four-ring structure is a tell-tale sign of cholesterol

Area A: This is the phosphate group. It is the polar head of the phospholipid molecule and consists of a phosphorus atom bonded to four oxygen atoms. The phosphate group is hydrophilic, meaning it attracts water.

Area B: This is the glycerol backbone. It is a three-carbon alcohol molecule that forms the central core of the phospholipid molecule. The glycerol backbone is also hydrophilic.

Area C: These are the fatty acid tails. They are two hydrocarbon chains, typically 14-20 carbons long, attached to the glycerol backbone by ester bonds. The fatty acid tails are hydrophobic, meaning they repel water.

Area D: This is the nitrogenous base. It is a molecule containing a nitrogen atom, such as choline or ethanolamine, attached to the phosphate group by a phosphodiester bond. The nitrogenous base can be either hydrophilic or hydrophobic depending on its specific structure

Dehydration synthesis is the best description for the formation of lipids. This process involves the removal of water molecules to join smaller molecules together and form larger molecules. In the case of lipids, dehydration synthesis occurs when glycerol and fatty acids combine to form triglycerides. This reaction releases a water molecule for each bond formed, resulting in the synthesis of lipids.

Lipids and carbohydrates have different compositions. Lipids, including fats and oils, are composed of carbon, hydrogen, and oxygen, but the ratio of hydrogen to oxygen is higher than in carbohydrates. Carbohydrates, such as sugars and starches, have a 1:2:1 ratio of carbon, hydrogen, and oxygen.

Detergent molecules are amphoteric.

Lipids are organic molecules characterized by their hydrophobic nature, meaning they do not mix well with water. This is primarily because lipids consist of long hydrocarbon chains or rings, which are nonpolar and do not interact favorably with polar water molecules. Lipids play essential roles in energy storage, membrane structure (as in phospholipids), and signaling in the form of hormones and other molecules.

Lipids are a diverse group of organic compounds that are primarily composed of carbon (C), hydrogen (H), and oxygen (O). Unlike carbohydrates, lipids do not have a specific ratio of these elements; their composition varies widely depending on the type of lipid. While some lipids may contain small amounts of other elements like nitrogen (N), phosphorus (P), or sulfur (S), the primary elements found in lipids are C, H, and O. Therefore, option C is the most accurate description of the composition of lipids.

This is clearly a triglyceride: Glycerol bonded to 3 fatty acids. The second and third fatty acids have bent chains, indicating that they're unsaturated fatty acids. Hence this is more likely to be an oil than a solid fat.

All 3 can form, depending on concentration. They form spontaneously, based on hydrophobic-hydrophilic interactions.

Liposomes are hollow spheres; capturing the right chemical mix plus a little DNA or RNA gives you a primitive cell.