Question

Assertion (A): Lipids are not true Biomacromolecules.
Reason (R): The molecular weight of lipids is less than 800 Daltons.

• A. Both (A) and (R) are correct, R is correct explanation for (A)
• B. Both (A) and (R) are correct. But (R) is not correct explanation for (A)
• C. (A) is true, but (R) is false
• D. (A) is false but (R) is true

Answer 1

The Correct Option is C

Assertion (A):

Biomacromolecules are typically defined as large molecules formed by the polymerization of repeating smaller subunits (monomers), such as proteins (from amino acids), nucleic acids (from nucleotides), and polysaccharides (from monosaccharides).
Lipids are a diverse group of organic molecules crucial for life (e.g., fats, oils, phospholipids, steroids). However, they are generally not polymers in the strict sense, as they are not formed from the repetitive linking of identical or similar monomeric units.
For instance, a triglyceride is formed from glycerol and three fatty acids, not repeating identical units.
Therefore, the assertion that lipids are not true biomacromolecules (in the sense of being polymers) is considered True.

Reason (R):

This statement claims that the molecular weight of lipids is less than 800 Daltons.
Let’s consider examples of common lipids:
  – Fatty acids typically have molecular weights ranging from approximately 200 to 400 Daltons.
  – Triglycerides, which are a major class of lipids, are formed from one glycerol molecule and three fatty acid molecules. Their molecular weights can easily exceed 800 Daltons. For example, tripalmitin (a common triglyceride composed of glycerol and three palmitic acids) has a molecular weight of $$807 \text{ Daltons}$$. Tristearin has an even higher molecular weight.
  – Other complex lipids like phospholipids and some steroids also have molecular weights that can be significantly higher than 800 Daltons.
Therefore, the statement that the molecular weight of lipids is less than 800 Daltons is generally False.

Evaluation of the relationship between (A) and (R):

We found that Assertion (A) is True.
We found that Reason (R) is False.
Since Reason (R) is false, it cannot be a correct explanation for Assertion (A).

Correct Option:

The option that states ” (A) is true, but (R) is false” aligns with our analysis.
The final answer is 3.