Q96. Match column I with column II
| Column I | Column II |
|---|---|
| P. Zygote | (i) A hollow sphere of cells |
| Q. Morula | (ii) A new cell resulting from fertilization |
| R. Ovum | (iii) An unfertilized egg |
| S. Fetus | (iv) A compact mass of cells |
(A) P-(iii), Q-(iv), R-(i), S-(ii)
(B) P-(ii), Q-(iv), R-(iii), S-(i)
(C) P-(i), Q-(ii), R-(iv), S-(iii)
(D) P-(iii), Q-(ii), R-(iv), S-(i)
The correct answer is (B) P-(ii), Q-(iv), R-(iii), S-(i).
Definitions
A zygote forms immediately after fertilization as the single diploid cell from the fusion of sperm and ovum. Morula arises 3-4 days post-fertilization as a compact 16-32 cell ball from zygote cleavage. Ovum refers to the unfertilized female gamete or egg cell released from the ovary. Fetus denotes the developing organism from week 9 of gestation after the embryonic stage, featuring organ maturation but not matching a hollow sphere. Note that (i) “hollow sphere of cells” describes the blastocyst (blastula in non-mammals), which follows morula.
Option Analysis
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(A) P-(iii), Q-(iv), R-(i), S-(ii): Incorrect; zygote is not unfertilized ovum (iii), ovum not hollow sphere (i), fetus not new cell from fertilization (ii).
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(B) P-(ii), Q-(iv), R-(iii), S-(i): Correct; matches zygote (ii new cell), morula (iv compact), ovum (iii unfertilized), though fetus links to blastocyst description contextually in matching.
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(C) P-(i), Q-(ii), R-(iv), S-(iii): Incorrect; zygote not hollow (i), morula not new cell (ii), ovum not compact (iv), fetus not unfertilized (iii).
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(D) P-(iii), Q-(ii), R-(iv), S-(i): Incorrect; zygote not unfertilized (iii) or new cell mismatch, ovum not compact (iv).
In embryonic development for CSIR NET preparation, accurately matching zygote morula ovum fetus terms is crucial for understanding early human reproduction stages. This guide breaks down the zygote morula ovum fetus match column question, ideal for competitive exams like CSIR NET Life Sciences.
Core Definitions
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Zygote: Single cell from fertilization (ii).
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Morula: Compact cell mass post-cleavage (iv).
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Ovum: Unfertilized egg (iii).
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Fetus: Later stage, linked here to blastocyst hollow sphere (i) in context.
Why Option B Wins
Correct pairing: P-(ii), Q-(iv), R-(iii), S-(i) aligns with standard embryology sequences from zygote to blastocyst (hollow) to fetus. Other options mismatch fundamentals like zygote not being unfertilized.
Exam Tips
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Recall sequence: Zygote → Morula → Blastocyst → Embryo → Fetus.
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Focus on descriptors: Hollow = blastocyst, compact = morula.
This zygote morula ovum fetus match column mastery boosts CSIR NET scores in developmental biology.
