Find the best tutors and institutes for Class 11 Tuition
Q4:
What is $G_0$ (quiescent phase) of cell cycle?
Solution :
Theoretical Definition of the $G_0$ Phase
The $G_0$ phase, colloquially known as the quiescent phase, represents a state in which cells exit the active cell cycle (post-mitosis) and enter a period of metabolic activity without undergoing division. This state is regulated by specific extracellular signals and intracellular checkpoints [Per the Cell Cycle Regulation Model].
Step 1: Mechanism of Entry into Quiescence
Following the completion of mitosis ($M$ phase), cells enter the $G_1$ phase. If the environmental conditions—such as nutrient availability, growth factors, or cell density—are suboptimal, the cell does not pass the Restriction Point (R-point). Instead, it transitions into the $G_0$ phase. During this transition, the expression of cyclins and cyclin-dependent kinases ($CDKs$) required for the $S$ phase is downregulated [By the Retinoblastoma Protein ($pRb$) pathway].
Step 2: Physiological and Metabolic Characteristics
While the cell is not dividing, it remains biologically functional. The $G_0$ phase is characterized by the following criteria:
- Metabolic Activity: The cell maintains homeostatic functions, protein synthesis, and respiration.
- DNA Content: The DNA remains in a $2C$ state (diploid), as the cell has not yet entered the $S$ phase ($DNA$ synthesis).
- Reversibility: Depending on the cell type, this state may be permanent (e.g., neurons) or temporary (e.g., hepatocytes or lymphocytes).
Step 3: Schematic Representation of the Cell Cycle
Step 4: Comparative Analysis of Cell Fate
| Category | Description |
|---|---|
| Reversible Quiescence | Cells like fibroblasts can re-enter the cell cycle upon stimulation by growth factors. |
| Terminal Differentiation | Cells like cardiac myocytes or neurons exit the cycle permanently after maturation. |
Final Solution: The $G_0$ (quiescent) phase is an inactive state of the cell cycle where cells exit the proliferative cycle ($G_1$ phase) due to lack of growth signals or metabolic constraints. These cells remain metabolically active but do not replicate their DNA ($S$ phase) or undergo division, essentially functioning as differentiated cells in a state of suspended animation.
More Questions from Class 11 Biology Cell Cycle and Division EXERCISES
- Q1: What is the average cell cycle span for a mammalian cell?
- Q2: Distinguish cytokinesis from karyokinesis.
- Q3: Describe the events taking place during interphase.
- Q5: Why is mitosis called equational division?
- Q6(i): Name the stage of cell cycle at which one of the following events occur: (i) Chromosomes are moved to spindle equator.
- Q6(ii): Name the stage of cell cycle at which one of the following events occur: (ii) Centromere splits and chromatids separate.
- Q6(iii): Name the stage of cell cycle at which one of the following events occur: (iii) Pairing between homologous chromosomes takes place.
- Q6(iv): Name the stage of cell cycle at which one of the following events occur: (iv) Crossing over between homologous chromosomes takes place.
- Q7(a): Describe the following: (a) synapsis Draw a diagram to illustrate your answer.
- Q7(b): Describe the following: (b) bivalent Draw a diagram to illustrate your answer.
- Q7(c): Describe the following: (c) chiasmata Draw a diagram to illustrate your answer.
- Q8: How does cytokinesis in plant cells differ from that in animal cells?
- Q9: Find examples where the four daughter cells from meiosis are equal in size and where they are found unequal in size.
- Q10: Distinguish anaphase of mitosis from anaphase I of meiosis.
- Q11: List the main differences between mitosis and meiosis.
- Q12: What is the significance of meiosis?
- Q13(i): Discuss with your teacher about (i) haploid insects and lower plants where cell-division occurs, and
- Q13(ii): Discuss with your teacher about (ii) some haploid cells in higher plants where cell-division does not occur.
- Q14: Can there be mitosis without DNA replication in ‘S’ phase?
- Q15: Can there be DNA replication without cell division?
- Q16(i): Analyse the events during every stage of cell cycle and notice how the following two parameters change (i) number of chromosomes ($N$) per cell
- Q16(ii): Analyse the events during every stage of cell cycle and notice how the following two parameters change (ii) amount of DNA content ($C$) per cell
CBSE Solutions for Class 11 Biology Cell Cycle and Division
Chapters in CBSE - Class 11 Biology
- The Living World
- Biological Classification
- Plant Kingdom
- Animal Kingdom
- Morphology of Flowering Plants
- Anatomy of Flowering Plants
- Structural Organisation in Animals
- Cell – The Unit of Life
- Biomolecules
- Transport in Plants
- Mineral Nutrition
- Photosynthesis
- Respiration in Plants
- Plant Growth and Development
- Digestion and Absorption
- Breathing and Exchange of Gases
- Body Fluids and Circulation
- Excretory Products and Elimination
- Locomotion and Movement
- Neural Control and Coordination
- Chemical Coordination and Integration
Top Tutors who teach Cell Cycle and Division
Top Tutor
Paschim Vihar, Delhi
Less than a yr
Exp
5 students
144 hrs of classes completed
500
per hour
Online Classes
Student's Home
Tutor's home
I am a home tutor and teaching physics & mathematics up to class 12 for last 8 years. I am NET 2018, GATE 2013 & GATE 2011 qualified. My highest qualification is MTECH. I am an engineering graduate.
Sir you really make your students to learn and read in a manner where you they knowledge with confidence.
Super Tutor
Pandri, Raipur
4 yrs of
Exp
45 students
3228 hrs of classes completed
520
per hour
Online Classes
Hello, my name is Atulya Kumar. I have completed my engineering from IIT (ISM), Dhanbad and am currently pursuing a PhD in Civil Engineering at IIT (ISM), Dhanbad. Teaching physics has been both a passion and a purpose since 2019, and over the years, I have mentored Class XI and XII students, particularly those preparing for JEE Main, JEE Advanced, NEET, and board examinations. I specialize in teaching Class 12 and 11 Physics in a result-oriented and concept-focused manner. My classes are tailored to bridge the gap between theory and application, ensuring students not only understand the fundamentals but can also apply them effectively in competitive exams. In recent years, my students have consistently performed exceptionally well. For example, in NEET 2025, two of my students scored 653 and 639, while many achieved more than 99 percentile in JEE Main 2025. In earlier years, students under my guidance secured AIR 2513 in NEET 2022 and AIR 1702 in NEET 2023, with many crossing the 98th percentile in JEE Main 2023. I adopt a structured approach, focusing on topic-wise concept clarity, MCQ drills, PYQ (previous year questions) practice, and mock test simulations. My JEE sessions emphasize critical topics such as modern physics, electromagnetism, kinematics, and thermodynamics, while NEET classes are tailored toward speed, accuracy, and NCERT alignment. I also give equal importance to board exam preparation, guiding students to score above 90% in Physics through clear explanations, derivation practice, answer writing techniques, and mock board tests. Teaching physics is a personal challenge and joy for me. I strive to build a learning environment where students feel confident, curious, and capable. It’s deeply fulfilling to watch them grow from conceptual struggles to academic excellence, and I remain committed to their success—both in exams and in life.
Knowledgeable tutor. Good hold on physics; all topics covered. My daughter is preparing for NEET exams and is studying physics from Atulya G.
Top Tutor
Mukherjee Nagar, Delhi
5 yrs of
Exp
2055 hrs of classes completed
500
per hour
Online Classes
Hi, I am Neeraj Dwivedi Top Tutor and partner at Urban Pro . Into profession of teaching since last four years. Expertise and specialization in guiding students on subjects like History, Political Science, Economics and Hindi. These subjects were my strength in my journey of Civil Services and later helped in shaping future of students. Apart from teaching guidance I have been doing career counselling of students as to what to pursue/not pursue after school based on individual interests and capabilities.
I scored above in all three subjects and you are good in explaining the details, I really amazed by your teaching style.
Super Tutor
Lalpur, Ranchi
9 yrs of
Exp
12 students
3187 hrs of classes completed
600
per hour
Online Classes
I am a qualified and dedicated teacher, having 10 years of teaching and research experience across different boards including CBSE, ICSE, IGCSE, IB, GCSE, and Australian Board. I specialize in guiding students from Class 8 to Post Graduation, helping them achieve academic excellence with a tailored and engaging teaching approach. I bring in-depth knowledge and expertise to my sessions. Qualifications: • Ph. D (Science) – BIT Mesra, Ranchi • CSIR UGC NET (2011) AIR-14 • ICAR NET (2010) • ICAR NET (2018) • GATE (2009) My student-centered approach focuses on assessing individual learning needs, bridging knowledge gaps, and fostering critical thinking through interactive methods like discussions, visual aids, and hands-on activities. Regular feedback and personalized guidance empower students to excel and develop a lifelong love for learning.
Dr. Gulsaz is an excellent teacher. Explains the concept with a lot of patience. Explains the origin of words in the su ject from the Latin, Greek roots. So, it is easy remember.
Top Tutor
Behala, Kolkata
6 yrs of
Exp
4 students
1162 hrs of classes completed
1000
per hour
Online Classes
Student's Home
Tutor's home
As a passionate mathematics teacher, I have always enjoyed imparting knowledge to others. I am a B.Tech graduate in Electronics and Communication. I have been teaching mathematics for over four years, and my love for the subject has grown stronger with time. I started teaching as a part-time tutor while pursuing my engineering degree and fell in love with the profession. After completing my degree, I worked with Byjus, one of the leading Edtech companies in India, as a mathematics teacher for two years. While I enjoyed my time at Byju's, I could do more as a teacher and wanted to explore new avenues. I joined Vedantu, an online learning platform, where I have been teaching mathematics for the last two years. I started my journey as a math teacher out of pure passion. Mathematics has always been my favourite subject, and I enjoyed solving problems and equations from a young age. As I grew older, I realised I had a natural talent for teaching, and I decided to pursue it as a career. Currently, I provide mathematics classes for students from sixth to twelfth for all boards, including ICSE, CBSE, and West Bengal. I teach offline and online classes, each lasting for one and a half hours. I use interactive tools such as Zoom, Pentab, and One Note to make my lessons engaging and interactive for my students. To help my students excel in mathematics, I provide them with reference books, notes, and in-built assignments to test their knowledge. I also conduct monthly tests to assess their progress and identify improvement areas. Teaching on UrbanPro has allowed me to interact with students from different parts of the country and help them realise their full potential in mathematics. I want to continue making a positive impact in the lives of my students and help them develop a love for mathematics, just like I did
Sirs class is very interactive, explains each topic in detail making it crystal clear for the student to understand and learn. Always approachable and is ready to clear doubts anytime.
