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Question #45540
The Question
A couple uses a cervical cap coated with a spermicidal jelly. Due to a microscopic tear, several sperm physically bypass the mechanical barrier and enter the uterus while maintaining vigorous flagellar motility. However, fertilization still fails to occur. Which of the following best explains the biochemical reason for this failure?
Options
- A.
The mechanical bypass prevents the sperm from undergoing capacitation, a process that normally occurs in the epididymis.
- B.
The spermicidal jelly prematurely triggers the cortical reaction in the secondary oocyte, hardening the zona pellucida.
- C.
The altered pH and ionic environment from the spermicide prevents cholesterol efflux and calcium influx, inhibiting capacitation.
- D.
The sperm are unable to undergo the acrosomal reaction because spermicides directly denature the ZP3 receptors on the ovum.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Fallopian_Tube|Vaginal_pH|Capacitation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often equate sperm motility directly with fertilizing capacity and confuse the location of sperm maturation (epididymis) with capacitation (female reproductive tract).
This question tests the NCERT-Plus application that barrier methods with spermicides provide a dual mechanism: even if the mechanical barrier fails, the biochemical alteration of the female tract inhibits capacitation, rendering motile sperm functionally sterile.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Reproductive Health - Class 12 |
| Concept | Barrier Method Dynamics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |