Population, Quantitative & Conservation Genet

• Omega-3 Fatty Acids in Fish Oils:
• Marine fish oils are exceptionally rich in omega-3 ($\omega-3$ or $n-3$) long-chain polyunsaturated fatty acids, specifically Eicosapentaenoic Acid (EPA, $20:5\, n-3$) and Docosahexaenoic Acid (DHA, $22:6\, n-3$).
• These fatty acids provide cardiovascular protection, reduce systemic inflammation, lower serum triglycerides, and support human neural and retinal development.
• Correct Option: Option 4 (omega-3-fatty acids).

• Adaptive Potential of Populations:
• Genetic Diversity: The variety of alleles and genotypes present within a species or population.
• High genetic diversity provides the raw material for natural selection. When facing novel environmental stressors (climate change, emerging pathogens, salinity shifts), genetically diverse populations are more likely to possess alleles conferring tolerance, preventing extinction.
• nalysis:
• (genetic diversity): Correct.
• (phenotypic diversity): Outward manifestation; without underlying genetic variation, phenotypic plasticity cannot ensure long-term evolutionary survival.

Correct option: (2) genetic diversity

• Branchial Compensation of Respiratory Acidosis:
• Environmental hypercapnia (elevated water $CO_2$) causes hydration of $CO_2$ in fish blood, producing carbonic acid and driving down intracellular and extracellular $\text{pH}$ (respiratory acidosis):

• Fishes compensate by actively excreting $H^+$ ions and retaining/accumulating bicarbonate ions ($HCO_3^-$) via branchial gill epithelia exchangers ($Na^+/H^+$ and $Cl^-/HCO_3^-$), elevating plasma bicarbonate to restore systemic blood $\text{pH}$.
• Correct Option: Option 4 (Bicarbonate concentration).