Q.145 Zoology ⭐ 360° Option Elimination Active

NEET 2026 Zoology Question 145 Solution

Topic: Human Reproduction · Official NTA Booklet Code 50

Question

Given below are two statements: Statement I: Ovulation is caused by LH surge leading to rupture of Graafian follicles. Statement II: Graafian follicle remaining after ovulation transform into corpus luteum and secretes large amount of estrogen. In the light of the above statements, choose the most appropriate answer from the options given below:

(1)Both Statement I and Statement II are correct
(2)Both Statement I and Statement II are incorrect
(3)Statement I is correct but Statement II is incorrect
(4)Statement I is incorrect but Statement II is correct

✓

Verified Against NTA Final Answer Key

Option (3) : Statement I is correct but Statement II is incorrect

📚 Human Reproduction Medium

📋 Given Parameters & Problem Setup

Statement I Ovulation is caused by LH surge leading to rupture of Graafian follicles.

Statement II Graafian follicle remaining after ovulation transform into corpus luteum and secretes large amount of estrogen.

⚡

The 30-Second Exam Hall Shortcut: ⚡ Corpus Luteum Hormone Rule

⏱️ Save ~40 seconds

LH Surge triggers Ovulation (True); Corpus Luteum secretes PROGESTERONE, not estrogen (Statement II is False)!

1 Evaluate Statement I: Rapid mid-cycle secretion of Luteinizing Hormone (LH surge) triggers rupture of the mature Graafian follicle and release of the ovum. -> Statement I is TRUE.

2 Evaluate Statement II: The ruptured follicle transforms into the corpus luteum, which secretes large amounts of PROGESTERONE (essential for maintaining the endometrium), NOT large amounts of estrogen. -> Statement II is FALSE!

3 Conclusion: Statement I is correct but Statement II is incorrect.

4 Select Option (3) in under 10 seconds!

🛡️

Why You Can 100% Trust This Shortcut: NCERT Biology · Human Reproduction (Luteal Phase: Corpus luteum secretes progesterone essential for endometrium maintenance).

📐

Step-by-Step Rigorous Workflow & Mathematical Proof

Step 1

Analyze Statement I: Mechanism of Ovulation

Both LH and FSH attain a peak level in the middle of the menstrual cycle (around day 14). Rapid secretion of LH leading to its maximum concentration (termed the LH surge) induces rupture of the mature tertiary Graafian follicle and release of the secondary oocyte into the peritoneal cavity.

\text{LH Surge (Day 14)} \longrightarrow \text{Rupture of Graafian Follicle} \longrightarrow \mathbf{Ovulation\text{ [Statement I is TRUE]}}

• Statement I is factually and physiologically accurate.

Step 2

Analyze Statement II: Endocrine Secretion of Corpus Luteum

Following ovulation, the remaining granulosa and theca cells of the ruptured Graafian follicle undergo luteinization under LH stimulation to form a yellow endocrine body, the corpus luteum. The corpus luteum secretes large quantities of PROGESTERONE, which maintains the secretory endometrium for implantation.

\text{Corpus Luteum} \xrightarrow{\text{Secretes}} \mathbf{Large\text{ amounts of Progesterone}} \; (\text{NOT large amounts of estrogen})

• While a minor amount of estrogen is produced, progesterone is the primary, defining hormone.
• Stating that it "secretes large amount of estrogen" is a classic NTA trap and is incorrect.

Step 3

Determine the Correct Option

Statement I is correct, but Statement II is incorrect. This corresponds to Option (3).

\text{Statement I is correct but Statement II is incorrect} \implies \text{Option (3)}

• Matches official NTA final answer key Option C / (3).

⭐

360° Option Elimination Engine Key Feature

Diagnose every choice: Know exactly why the right option works and why distractors fail.

4-Option Deep Scan

1 A

✗ Incorrect

Verdict & Scientific Reason:

Incorrect. Fails to catch that corpus luteum predominantly secretes progesterone, not estrogen.

⚠️

Student Fallacy (Why candidates pick this trap): Overlooking the specific hormone of the luteal phase.

2 B

✗ Incorrect

Verdict & Scientific Reason:

Incorrect. Statement I is a fundamental medical truth (LH surge causes ovulation).

⚠️

Student Fallacy (Why candidates pick this trap): Doubting LH surge mechanism.

3 C

✓ 100% Correct

Verdict & Scientific Reason:

100% accurate. Statement I is correct, while Statement II erroneously claims large estrogen secretion instead of progesterone.

💡

Why this is airtight: None; mastered ovarian cycle endocrinology.

4 D

✗ Incorrect

Verdict & Scientific Reason:

Completely inverted.

⚠️

Student Fallacy (Why candidates pick this trap): Total conceptual reversal.

⚠️

NTA Trap Alert: Follicular vs Luteal Hormone Trap

Growing ovarian follicles secrete ESTROGEN (proliferative phase); Corpus luteum secretes PROGESTERONE (secretory/luteal phase). NTA regularly swaps these two phases.

🛡️ How to avoid the -1 mark: Follicle = Estrogen; Corpus Luteum = Progesterone!

📖

Core NEET Syllabus Standard

NEET Biology Core Syllabus · Human Reproduction Standard Benchmark

Core Scientific Principle Tested:

"Ovulation is triggered by the mid-cycle LH surge. The resulting corpus luteum secretes high levels of progesterone to maintain pregnancy."

Syllabus Focus: Menstrual Cycle

✓ Core NEET UG Syllabus Anchor Syllabus & Academic Standards ↗

Follicles emit Estrogen to build the nest; Corpus Luteum pumps Progesterone so the embryo can rest!

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NEET 2026 Zoology Question 145 Solution

Question

The 30-Second Exam Hall Shortcut: ⚡ Corpus Luteum Hormone Rule

Step-by-Step Rigorous Workflow & Mathematical Proof

Analyze Statement I: Mechanism of Ovulation

Analyze Statement II: Endocrine Secretion of Corpus Luteum

Determine the Correct Option

360° Option Elimination Engine Key Feature

NTA Trap Alert: Follicular vs Luteal Hormone Trap

Core NEET Syllabus Standard

Ready to attempt under real exam pressure?

🔗 Related Questions — Human Reproduction

Structure and Function of Human Spermatozoon

Chronology of Human Gestational Milestones

Comparison of Spermatogenesis vs Oogenesis and Hormonal Control

Terminology of Menstrual Milestones (Menarche vs Menopause)

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