Problem 80 - Objective Biology for NEET

Question

Which one of the following is a secondary metabolite? (a) Amino acid (b) Sugar (c) Flavonoides and antibiotics (d) Protein

Step-by-Step Solution

Answer

The correct choice is (c) Flavonoids and antibiotics. These are examples of secondary metabolites.

Step 1: Identify the Primary Metabolites

Proteins, sugars, and amino acids are primary metabolites. They directly aid in the growth and development of an organism and are necessitated for basic survival.

Step 2: Recognize the Secondary Metabolites

Secondary metabolites are not directly involved in growth, development or reproduction but serve other important functions. Flavonoids and antibiotics fall under this category as they are typically involved in defense mechanisms.

Step 3: Decide the Correct Option

From the above analysis and understanding, the correct choice is Flavonoids and antibiotics. These are secondary metabolites, unlike sugars, proteins, and amino acids which are primary metabolites.

Key Concepts

Primary Metabolites

Primary metabolites are essential compounds produced by all living organisms. They play a crucial role in the normal growth, development, and reproduction of these organisms. Without them, life processes like metabolism would halt.

• Amino Acids: These are the building blocks of proteins, which are vital for structure and function in cells.
• Sugars: Simple sugars like glucose provide energy necessary for cellular activities.
• Proteins: Proteins perform various functions including enzyme catalysis and transport within living organisms.

These metabolites are constantly present in the cells, facilitating key metabolic pathways and allowing organisms to thrive in their environment.

Flavonoids

Flavonoids are a group of plant-based compounds that serve many beneficial functions. Although they are secondary metabolites, they help plants in ways that extend beyond basic survival.

• Defense Mechanisms: They aid plants in protecting against pathogens and pests.
• Coloration: Flavonoids contribute to the vibrant colors of flowers and fruits, which can attract pollinators.
• Antioxidants: These compounds have antioxidative properties, which can prevent cell damage.

Even though flavonoids aren't necessary for the plant to survive like primary metabolites, they significantly enhance the plant's ability to interact and adapt to its environment.

Antibiotics

Antibiotics are another type of secondary metabolite that have a significant impact, especially in the realm of human health. They are naturally produced by certain microorganisms to inhibit the growth of other microbes.

• Microbial Warfare: In nature, antibiotics are used by microbes to combat competition and secure resources by inhibiting rival microorganism growth.
• Medical Applications: This characteristic has been harnessed in medicine to treat bacterial infections in humans and animals, revolutionizing healthcare.
• Variety: Many different types of antibiotics exist, each targeting specific bacteria.

While organisms do not rely on antibiotics for their own survival, these substances play a critical role in ecological balance and human health.