Correct Option
The correct option is (a) 1 only.
Explanation
Fish possess specific physiological and anatomical adaptations that allow them to survive and move efficiently in an aquatic environment. These include streamlined bodies, specialized respiratory organs, and appendages for locomotion.Statement-wise Analysis:
- Statement 1 is Correct: Fish bodies are typically covered with scales that are slippery due to a natural secretion of mucus. This slippery surface serves two primary functions: it protects the fish from external parasites and infections, and it significantly reduces friction (drag) against the water, allowing for easy and efficient movement.
- Statement 2 is Incorrect: Fins and tails are primarily used for locomotion, maintaining balance, and changing direction while swimming. They are dynamic structures essential for mobility in the water column, rather than for anchoring the fish to the seabed.
- Statement 3 is Incorrect: Gills are specialized respiratory organs designed to extract oxygen that is dissolved in water. As water passes over the gill filaments, oxygen enters the bloodstream. Most fish cannot utilize atmospheric oxygen from the air above the water surface; their gills collapse and dry out when removed from the aquatic medium, leading to asphyxiation.
Key Takeaway: Fish adaptations include slippery scales to reduce drag, fins and tails for balance and steering, and gills specifically adapted for extracting dissolved oxygen from water.