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Question #45709
The Question
Freshwater teleosts are hyper-osmotic to their hypotonic environment, facing continuous passive water influx and solute efflux. To maintain osmoregulatory homeostasis, they must precisely modulate their Glomerular Filtration Rate (GFR) and ion exchange. Which of the following physiological adaptations is NOT characteristic of a freshwater teleost?
Options
- A.
Possession of large, well-developed glomeruli to maintain a high filtration fraction and excrete copious amounts of dilute urine.
- B.
Active uptake of Na⁺ and Cl⁻ ions from the surrounding water via specialized ionocytes (chloride cells) located in the gills.
- C.
Continuous ingestion of surrounding water coupled with active tubular secretion of divalent ions (Mg²⁺, SO₄²⁻) to prevent cellular lysis.
- D.
Elimination of the majority of nitrogenous waste as ammonia via passive diffusion across the gill epithelium, rather than through the kidneys.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Glomerular Filtration Fraction|Osmoregulation in Aquatic Adaptations|Nutrient Cycling Reservoirs
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Environmental Osmolarity vs.
Direction of Water Flow.
Students often memorize osmoregulatory mechanisms without distinguishing between the diametrically opposed challenges of freshwater (hypotonic) vs. marine (hypertonic) environments.
The trap relies on confusing the marine adaptation of drinking seawater and secreting divalent ions with the freshwater necessity of expelling water and retaining salts.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Excretory Products and Their Elimination - Class 11 |
| Concept | Glomerular Filtration Fraction |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |