NCERT Solutions Class 11 Biology Chapter 10

Cell cycle has two phases;

• Interphase

• G1 Stage (Gap 1)
• S Stage (Synthesis)
• G2 Stage (Gap 2)

• M phase

• Prophase
• Metaphase
• Anaphase
• Telophase

Stages involved in Meiosis are as follows;

• Meiosis I

• Prophase I (This phase is longer than that of the mitosis prophase)
• Metaphase I
• Anaphase I
• Telophase I

After Telophase once Cytokinesis has occurred, Meiosis II Prophase will begin. 

• Meiosis II

• Prophase II
• Metaphase II
• Anaphase II
• Telophase II

DNA replication can take place during the cell cycle’s G1 phase. The number of chromosomes stays the same as before and each chromosome is framed by one chromatid. Two sister chromatids joined at the centromere form the chromosome in the S stage. In the G2 stage, comparative conditions proceed. M stage has the sister chromatids acting independently and moving to various cells. In Mitosis, the number of chromosomes stays equivalent. In the cell, DNA content quantity stays the same as before during the G1 stage, however, in the S1 stage, it doubles. It stays double in the G2 stage but in the M phase of the cycle, it splits.

DNA replication is a process that involves the duplication of the DNA inside a cell. This occurs during cell division. An equal amount of identical replicas of DNA is given to every daughter cell. DNA carries information that is crucial for the repair, growth, and regeneration of tissues.

The Interphase has 3 basic stages that are categorized on the basis of how much a cell progresses. 

G1 Stage (Gap 1) – In this stage, though the cell is metabolically active and DNA is being developed and readied for replication, DNA replication does not take place. 

S Stage (Synthesis) – DNA synthesis or replication takes place in this phase. The DNA quantity doubles in this phase while the chromosome quantity remains unchanged. 

G2 Stage (Gap 2) – This is the stage between the S stage and the M phase. This is where the cell prepares itself for the process of cell division. RNA and proteins that are needed for mitosis are produced in this stage. 

G0 Stage- This is a stage where neither is a cell being divided nor is it preparing to divide. In adult animals, some cells do not show cell division while some that do divide, do it occasionally only when there is an occurrence of loss of cells caused due to cell death or injury. The cells not dividing exit the G1 phase and enter the G0 stage or the quiescent stage. In the G0 stage, cell division does not occur but the cell is metabolically active. 

The important topics of NCERT Class 11 Biology Chapter 10 Cell Cycle And Cell Division are:

• The span of cell cycle
• Mitosis and Meiosis
• Cytokinesis and Karyokinesis
• Synapsis
• Chiasmata
• Bivalent 
• DNA replication

Cell Cycle and Cell Division are discussed in detail in the Chapter 10 Biology Class 11 NCERT textbook. Stages in cell division, the change of DNA and chromosomes in the cell, the difference between mitosis and meiosis, and events during the interphase are the topics that are encompassed in the chapter. Referring to the explanations given in the NCERT Solutions Class 11 for Biology Chapter 10 will boost the confidence of the students and will help them tackle any kind of question in the exam. 

One can expect the following type of questions:

• Explain the cell cycle.

• What event occurs during the cell cycle?

• Differentiate between Mitosis and Meiosis.

• What is the importance of meiosis?

• Differentiate between cytokinesis and karyokinesis.

• Explain the events during the interphase.

• What is the significance/ importance of DNA replication?

• What is the change in DNA content in each cell?

• How does the number of chromosomes change in the cell cycle?

• 5 mark long answers are to be written in detail with relevant points covered in the answer. If the answer has diagrams as a part of it students must illustrate the same even if it is not specified in the question.

• Marks can be obtained easily through diagram questions so students are advised to practise the same. 

• MCQs carrying 1 mark are expected to be asked and to get these right a thorough preparation has to be done by students. 

The sex cells of both female and male reproductive organs of plants, as well as animals, have meiosis occurring in them. Male and female gametes (which take part in sexual reproduction) are produced by them. 

NCERT solutions have multiple benefits such as:

• They are framed while adhering to CBSE guidelines.
• Solutions are provided chapter-wise in a systematic manner.
• The solutions are easy to comprehend as they are written in a simple language with in-depth explanations. 
• Experts in the field with relevant experience have prepared the solutions.