Question

Following are the statements with reference to ??ipids. (a) Lipids having only single bonds are called unsaturated fatty acids. (b) Lecithin is a phospholipid. (c) Trihydroxy propane is glycerol. (d) Palmitic acid has 20 carbon atoms including carboxyl carbon. (e) Arachidonic acid has 16 carbon atoms. Choose the correct answer from the options given below.

• (a) and (b) only
• (c) and (d) only
• (b) and (c) only
• (b) and (e) only

Answer 1

The Correct Option is C

To address the question, we need to evaluate each statement related to lipids and identify which of these are correct based on known biological facts.

1. Statement (a): "Lipids having only single bonds are called unsaturated fatty acids."
   • This statement is incorrect. Lipids with only single bonds are called saturated fatty acids, not unsaturated. Unsaturated fatty acids have one or more double bonds.
2. Statement (b): "Lecithin is a phospholipid."
   • This statement is correct. Lecithin is indeed a type of phospholipid, which is a major component of cell membranes.
3. Statement (c): "Trihydroxy propane is glycerol."
   • This statement is correct. Glycerol, also known as glycerine, is a trihydroxy alcohol having the chemical structure \(C_3H_8O_3\) (or \(C_3H_5(OH)_3\)), meaning it has three hydroxyl (-OH) groups.
4. Statement (d): "Palmitic acid has 20 carbon atoms including carboxyl carbon."
   • This statement is incorrect. Palmitic acid has 16 carbon atoms, including the carboxyl carbon.
5. Statement (e): "Arachidonic acid has 16 carbon atoms."
   • This statement is incorrect. Arachidonic acid has 20 carbon atoms.

From the above evaluations, the correct statements are (b) and (c). Therefore, the correct answer is: (b) and (c) only.