50 Most Important NEET PYQs of Chapter 10: Cell Cycle and Cell Division – Part 1 (Q1–25) | By neetpyqall

-

 🧬 50 Most Important NEET PYQs of Chapter 10: Cell Cycle and Cell Division – Part 1 (Q1–25) | By neetpyqall

Let's dive into the first 25 most important and frequently asked NEET questions from Chapter 10 – Cell Cycle and Cell Division, along with clear, easy-to-understand solutions. This will help you revise smart and score sharp! ✅

1. What is the phase of the cell cycle where DNA replication occurs?

A) G1 phase
B) G2 phase
C) S phase
D) M phase
✅ Answer: C) S phase
📘 Explanation: The S or synthesis phase is when the DNA is replicated, doubling the DNA content of the cell.

2. Which stage of mitosis is characterized by the alignment of chromosomes at the equator?

A) Prophase
B) Metaphase
C) Anaphase
D) Telophase
✅ Answer: B) Metaphase
📘 Explanation: During metaphase, chromosomes line up at the metaphase plate (cell’s equator), attached to spindle fibers.

3. Synapsis occurs during:

A) Metaphase I
B) Prophase I
C) Anaphase I
D) Telophase I
✅ Answer: B) Prophase I
📘 Explanation: Synapsis, or pairing of homologous chromosomes, is a key feature of prophase I in meiosis.

4. The cell cycle is regulated by:

A) Ribosomes
B) Cyclins and CDKs
C) Lysosomes
D) Mitochondria
✅ Answer: B) Cyclins and CDKs
📘 Explanation: Cyclins and Cyclin-dependent kinases (CDKs) control the progression of cells through the cell cycle.

5. Which of the following is not a part of interphase?

A) G0 phase
B) G1 phase
C) S phase
D) M phase
✅ Answer: D) M phase
📘 Explanation: The M phase (mitotic phase) is separate from interphase, which includes G1, S, and G2 phases.

6. What is the diploid number of chromosomes in humans?

A) 23
B) 46
C) 92
D) 69
✅ Answer: B) 46
📘 Explanation: Humans have 46 chromosomes (23 pairs), making them diploid.

7. Crossing over occurs during:

A) Zygotene
B) Pachytene
C) Diplotene
D) Diakinesis
✅ Answer: B) Pachytene
📘 Explanation: During the pachytene stage of prophase I, homologous chromosomes exchange genetic material via crossing over.

8. The structure that holds sister chromatids together is:

A) Centrosome
B) Chromatin
C) Centromere
D) Spindle fiber
✅ Answer: C) Centromere
📘 Explanation: The centromere holds sister chromatids together until they are pulled apart during anaphase.

9. Which phase of mitosis follows metaphase?

A) Anaphase
B) Prophase
C) Telophase
D) Interphase
✅ Answer: A) Anaphase
📘 Explanation: In anaphase, sister chromatids are separated and pulled toward opposite poles.

10. In meiosis, the number of chromosomes is reduced to half during:

A) Meiosis I
B) Meiosis II
C) Mitosis
D) Interphase
✅ Answer: A) Meiosis I
📘 Explanation: Meiosis I is the reductional division where homologous chromosomes are separated.

11. Karyokinesis refers to:

A) Division of nucleus
B) Division of cytoplasm
C) DNA replication
D) Formation of spindle
✅ Answer: A) Division of nucleus
📘 Explanation: Karyokinesis is nuclear division; cytokinesis is the division of the cytoplasm.

12. How many mitotic divisions are needed to produce 128 cells from a single cell?

A) 64
B) 127
C) 7
D) 128
✅ Answer: C) 7
📘 Explanation: 2⁷ = 128, so 7 mitotic divisions are needed.

13. The point where crossing over occurs is called:

A) Centromere
B) Chromatid
C) Chiasma
D) Spindle
✅ Answer: C) Chiasma
📘 Explanation: Chiasmata are the visible sites of crossing over between homologous chromosomes.

14. During mitosis, spindle fibers attach to chromosomes at:

A) Centromere
B) Centrosome
C) Kinetochores
D) Chromatid
✅ Answer: C) Kinetochores
📘 Explanation: Spindle fibers attach to kinetochores, specialized structures on centromeres.

15. Which of the following occurs in anaphase I of meiosis?

A) Separation of chromatids
B) Separation of homologous chromosomes
C) Duplication of chromosomes
D) Synthesis of spindle fibers
✅ Answer: B) Separation of homologous chromosomes
📘 Explanation: Homologous chromosomes (not chromatids) are pulled apart in anaphase I.

16. G0 phase is characterized by:

A) DNA replication
B) Cell division
C) Quiescent stage
D) Cytokinesis
✅ Answer: C) Quiescent stage
📘 Explanation: G0 is a resting phase where cells are metabolically active but not dividing.

17. Centrioles duplicate in which phase of the cell cycle?

A) G1
B) S phase
C) G2 phase
D) M phase
✅ Answer: B) S phase
📘 Explanation: Along with DNA replication, centrioles also duplicate during the S phase.

18. Cell plate formation is a characteristic of:

A) Cytokinesis in animal cells
B) Cytokinesis in plant cells
C) Prophase
D) Anaphase
✅ Answer: B) Cytokinesis in plant cells
📘 Explanation: In plant cells, the cell plate forms between daughter nuclei and develops into a new cell wall.

19. What is the function of spindle fibers?

A) Attach chromatids to centromeres
B) Help in cell growth
C) Move chromosomes during division
D) Duplicate chromosomes
✅ Answer: C) Move chromosomes during division
📘 Explanation: Spindle fibers pull chromosomes toward the poles during anaphase.

20. The nuclear envelope reappears during:

A) Prophase
B) Metaphase
C) Anaphase
D) Telophase
✅ Answer: D) Telophase
📘 Explanation: In telophase, the nuclear membrane reforms around each set of chromosomes.

21. Leptotene is a stage of:

A) Prophase I
B) Anaphase II
C) Metaphase I
D) Telophase I
✅ Answer: A) Prophase I
📘 Explanation: Leptotene is the first sub-stage of prophase I in meiosis.

22. How many chromatids are present in a human cell at the end of S phase?

A) 23
B) 46
C) 92
D) 69
✅ Answer: C) 92
📘 Explanation: After DNA replication, each of the 46 chromosomes has two chromatids: 46 × 2 = 92.

23. What marks the end of prophase?

A) DNA replication
B) Disappearance of nuclear envelope
C) Chromosome condensation
D) Spindle formation
✅ Answer: B) Disappearance of nuclear envelope
📘 Explanation: The breakdown of the nuclear envelope signals the transition from prophase to metaphase.

24. The duration of cell cycle is longest in:

A) G1 phase
B) S phase
C) M phase
D) G2 phase
✅ Answer: A) G1 phase
📘 Explanation: G1 is usually the longest phase where the cell grows and prepares for DNA replication.

25. In animal cells, cytokinesis is achieved by:

A) Cell plate formation
B) Furrow formation
C) Spindle formation
D) Budding
✅ Answer: B) Furrow formation
📘 Explanation: In animal cells, a cleavage furrow forms to divide the cytoplasm during cytokinesis.

🔜 Stay tuned for Part 2 (Q26–50) of Chapter 10!

📚 For complete NEET biology preparation, visit:
🔗 neetpyqall.blogspot.com
🔗 biologyatease1.blogspot.com


Comments

Post a Comment

Popular posts from this blog

50 Most Important NEET PYQs of Chapter "Living World" with Detailed Solutions

-
 Certainly! Below is a complete set of 50 Most Important NEET PYQs of Chapter "Living World" with detailed solutions. The blog concludes with a call to follow @neetpyqall for more updates. 50 Most Important NEET PYQs of Chapter "Living World" with Detailed Solutions Welcome to a comprehensive guide to the Living World chapter from your NEET Biology syllabus. This chapter forms the foundation for understanding biological classification, characteristics of life, and the diversity of organisms. Here, we cover 50 crucial previous year questions (PYQs) from NEET, with detailed answers and explanations. 1. Question : Which of the following is NOT a characteristic feature of living organisms? A) Growth B) Ability to reproduce C) Inability to respond to stimuli D) Metabolism Answer : C) Inability to respond to stimuli Explanation : Living organisms respond to external stimuli, which is a fundamental characteristic of life. The other options—growth...
Read more

NEET PYQs – Chapter 2: Biological Classification (Top 50 Questions with Detailed Solutions)

-
 Got it! Here's your complete blog-style post with 50 most important NEET previous year questions from Chapter 2 – Biological Classification , including answers and detailed solutions. 🧬 NEET PYQs – Chapter 2: Biological Classification (Top 50 Questions with Detailed Solutions) Perfect for NEET 2025 aspirants! Dive into these handpicked questions from previous years to master the concepts of this chapter. 1. Five Kingdom Classification was Proposed by: A) Carolus Linnaeus B) R.H. Whittaker C) Aristotle D) Ernst Haeckel ✅ Answer: B) R.H. Whittaker Explanation: In 1969, R.H. Whittaker introduced the five kingdom classification: Monera, Protista, Fungi, Plantae, and Animalia. 2. Kingdom Monera Consists of: A) Multicellular organisms B) Unicellular eukaryotes C) Unicellular prokaryotes D) Multicellular eukaryotes ✅ Answer: C) Unicellular prokaryotes Explanation: Monera includes bacteria and blue-green algae, which are unicellular and prokaryot...
Read more

50 Most Important NEET PYQs of Chapter 13: Photosynthesis in Higher Plants – Part 1 (Q1–25) | By neetpyqall

-
🌿 50 Most Important NEET PYQs of Chapter 13: Photosynthesis in Higher Plants – Part 1 (Q1–25) | By neetpyqall Get ready to master one of the most frequently asked and high-weightage chapters of NEET – Photosynthesis in Higher Plants . Below are 25 highly important Previous Year Questions (PYQs) with detailed explanations to help you gain conceptual clarity and improve accuracy in the exam. 1. Which of the following is a correct statement regarding photosynthesis? A) Oxygen is consumed B) CO₂ is released C) It is an exothermic reaction D) It is an endothermic reaction ✅ Answer: D) It is an endothermic reaction Explanation: Photosynthesis requires energy (sunlight) to convert CO₂ and H₂O into glucose, making it an endothermic process. 2. In which part of the chloroplast does the light reaction occur? A) Stroma B) Outer membrane C) Grana (thylakoid membranes) D) Inner membrane ✅ Answer: C) Grana (thylakoid membranes) Explanation: Light-dependent reactions occur in th...
Read more