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(a) Male bees, wasps and ants are haploid as they are produced from unfertilized eggs. 

(b) Cell division does not happen in synergids and antipodal cells; in the ovule.

DNA replication can take place without cells division; as in case of formation of new mitochondria and chloroplasts.

The division which maintain the number of chromosomes produced at the end of reduction division is called homotypic or equational division. Meiosis II stage is known as homotypic division.

(i) Meiosis: Meiosis is a double division that takes place in a diploid cell (2N) and involves reduction of chromosome number to half and forms four haploid cells. It reduces number of chromosomes to half. So it is popularly termed as the reduction division.

(ii) Amitosis : It is a simple method of cell division, also called direct cell division. In this, there is no differentiation of chromosomes and spindle. Nuclear envelope does not degenerate. Nucleus elongates and constricts in middle to form two daughter nuclei. It is followed by a centripetal constriction of cytoplasm to form 2 daughter cells.

(iii) G₂ phase (second growth phase) : It is also called pre-mitotic gap phase. It has double DNA content as compared to original cell (4C:2C). It produces macro-molecules (RNAs, proteins) for multiplication of organelles, spindle formation and cell growth. G phase prepares a cell to undergo division.

There cannot be mitosis without DNA replication, because additional DNAs are required for the formation of new cells.

Starts with nuclear division, corresponding to separation of daughter chromosomes (karyokinesis) and usually ends with division of cytoplasm (cytokinesis).

Students can go through the Important Class 11 Biology MCQ Questions of Cell Cycle and Cell Division with Answers. By practicing these questions, Students will clear concepts of this chapter. Class 11 Biology MCQ Questions of Cell Cycle and Cell Division with Answers are concerning the cycles in all living creatures canvassed in cell division. 

These MCQ Questions helps to understand patterns of questions posed in exams and it's prepared based on exam pattern and syllabus recommended by the CBSE board. This guarantees that understudies are improved with the approach that upgrades their knowledge.

Students can solve these MCQ Questions of Cell Cycle and Cell Division Class 11with answers and Check their preparation level. These Class 11 MCQ Questions with answers are helpful for speedy revisions of the Chapter.

Practice MCQ Questions for class 11 Biology Chapter-Wise

1. Cell plate grows from

(a) walls to the centre
(b) centre to the walls
(c) in patches
(d) simultaneously

2. During which stage the chromosomes first become visible.

(a) Anaphase
(b) Metaphase
(c) Prophase
(d) Telophase

3. How many chromosomes are there in the onion root tip cells?

(a) 06
(b) 16
(c) 26
(d) 36

4. The stage in which daughter chromosomes move toward the poles of the spindle is

(a) Anaphase
(b) Metaphase
(c) Prophase
(d) Telophase

5. If you are provided with root-tips of onion in your class and are asked to count the chromosomes which of the following stages can you most conveniently look into:

(a) Prophase
(b) Anaphase
(c) Telophase
(d) Metaphase

6. In mitosis, the nuclear envelope and nucleolus disappear during

(a) Metaphase
(b) Interphase
(c) Prophase
(d) Telophase

7. Chromosome duplication without nuclear division refers to

(a) mitosis
(b) endomitosis
(c) meiosis
(d) androgenesis

8. Recombination of genes occur at

(a) prophase I in meiosis
(b) prophase II in meiosis
(c) metaphase II in meiosis
(d) prophase in mitosis

9. The stage between two meiotic divisions is called interkinesis and

(a) Is generally short-lived and followed by prophase II
(b) Involves duplication of genes and centrioles
(c) Is followed by prophase I
(d) Is long-lived

10. Lampbrush chromosomes are seen in which typical stage?

(a) Meiotic prophase
(b) Mitotic prophase
(c) Mitotic anaphase
(d) Mitotic metaphase

11. Nucleoproteins are synthesized in 

(a) nucleoplasm
(b) nuclear envelope
(c) nucleolus
(d) cytoplasm

12. Segregation of Mendelian factor (Aa) occurs during 

(a) diplotene
(b) anaphase-I
(c) zygotene/pachytene
(d) anaphase-II

13.  Experiments on Acetabularia by Hammerling proved the role of 

(a) cytoplasm in controlling differentiation
(b) nucleus in heredity
(c) chromosomes in heredity
(d) nucleo-cytoplasmic ratio

14. The point, at which polytene chromosomes appear to be attached togethe

r, is called

(a) centriole
(b) centromere
(c) chromomere
(d) chromocentre

15. Chromatids coiling in the meiotic and mitotic division is............

(a) Plectonemic in both
(b) Paranemic in both
(c) Paranemic in mitosis and plectonemic in meiosis
(d) Plectonemic in mitosis and paranemic in meiosis

16. Chromosome structure can be observed best during..........

(a) Anaphase
(b) Metaphase
(c) Prophase
(d) None of the above

17. The exchange of segments of two non-homologous pair of chromosomes is termed as

(a) Crossing over
(b) Linkage
(c) transformation 
(d) translocation

18. The exchange of segments of non-sister chromatids between chromosomes of a homologous pair termed as

(a) transformation 
(b) translocation
(c) crossing over
(d) chromosomal aberration 

19. Calcium-dependent Kinases can control 

(a) cell cycle activities
(b) DNA replication 
(c) Cell surface receptors
(d) membrane structure

20. Many cells function properly and divide mitotically even though they do not have 

(a) Plasma membrane
(b) Cytoskeleton
(c) Mitochondria
(d) Plastids

21. The stage which serves as a connecting link between meiosis 1 and meiosis 2

(a) Interphase 2
(b) Interphase 1
(c) Interkineses
(d) None of the above

22. If an individual wants to view diakinesis, which of these would be

(a) Hair
(b) Leaf
(c) Onion root
(d) Flower bud

23. Best material for the study of mitosis in a laboratory is 

(a) anther
(b) root tip
(c) leaf tip
(d) ovary

24. During which phase of meiosis do Tetrads form?

(a) Metaphase I
(b) Telophase I
(c) Anaphase I
(d) Prophase I

25. What would be the number of chromosomes of the aleurone cells of a plant with 42 chromosomes in its root tip cells? 

(a) 42
(b) 63
(c) 84
(d) 21

Answer:

1. Answer: (b) centre to the walls

Explanation:  The cell plate grows from the center toward the cell walls. New cell walls are made from the vesicle contents.

2. Answer: (c) Prophase

Explanation: Prophase is the first stage of mitosis. In prophase, chromosomes condense and become visible.

3. Answer: (b) 16

Explanation:  Onion root tip cells have 16 chromosomes in each cell.

4. Answer: (a) Anaphase

Explanation:   The stage in which daughter chromosomes move toward the poles of the spindle is Anaphase.

5. Answer: (d) Metaphase

Explanation:   Metaphase is the best time to count and study the number and morphology of chromosomes.

6. Answer: (c) Prophase

Explanation:  During prophase, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down.

7. Answer: (b) endomitosis

Explanation: Endomitosis is the process of chromosome divides or doubles without nuclear division which leads to the formation of a polyploidy nucleus where one nucleus will have multiple sets of chromosomes. So, the correct answer is 'Endomitosis'.

8. Answer: (a) prophase I in meiosis

Explanation: Recombination occurs when two molecules of DNA exchange pieces of their genetic material with each other. One of the most notable examples of recombination takes place during meiosis (specifically, during prophase I), when homologous chromosomes line up in pairs and swap segments of DNA.

9. Answer: (a) Is generally short-lived and followed by prophase II

Explanation: The stage between two meiotic divisions is called interkinesis and is generally short-lived. Here the cell undergoes a period of rest. No DNA replication and no gene duplication occur during this stage. It is important for bringing true haploidy in daughter cells.

10. Answer: (a) Meiotic prophase

Explanation:  Chromosomes transform into the lampbrush form during the diplotene stage of meiotic prophase I due to the active transcription of many genes. They are highly extended meiotic half-bivalents, each consisting of 2 sister chromatids.

11. Answer:(d) cytoplasm

Explanation: Nucleoproteins are synthesized in the cytoplasm. Nucleoproteins are proteins that are linked structurally with nucleic acids, either RNA or DNA.

12. Answer: (b) anaphase-I

Explanation:  Segregation of Mendelian factor (Aa) occurs during Anaphase-I. The paired homologous chromosomes separate in meiosis-I so that each gamete receives one chromosome of each homologous pair.

13.Answer: (b) nucleus in heredity

Explanation: Hammerling's experiment of Acetabularia involved exchanging rhizoid and stalk. Presence of hereditary information in the nucleous was proved by the work of Hammerling on single-celled alga Acetabularia.

14. Answer: (d) chromocentre

Explanation:  Chromocenter is the point at which polytene chromosomes appear to be attached together.

15. Answer: (d) Plectonemic in mitosis and paranemic in meiosis

Explanation:  Plectonemic coiling occurs in mitosis and Paranemic coiling occurs in meiosis. DNA is coiled and shortened about sevenfold of its length which means that the DNA of 1 m long becomes 14 cm in its strings of beads.

16. Answer: (b) Metaphase

Explanation: The best time to study chromosome size and shape is metaphase/late prophase.

17. Answer: (d) translocation

Explanation: The exchange of segments of non-homologous chromosomes is called Translocation.

18. Answer: (c) crossing over

Explanation: An exchange of chromosome segments between non-sister homologous chromatids occurs and is called crossing over. The crossover events are the first source of genetic variation produced by meiosis.

19. Answer: (a) cell cycle activities

Explanation: Calcium Dependent Kinases (CDKs) have the ability to control cell cycle activities during cell division.

20.Answer: (d) Plastids

Explanation: The presence of plastid is a feature of plant cells but animal cells are devoid of them. Even then they function properly and divide mitotically similar to plant cells.

21. Answer:  (c) Interkineses

Explanation: The connecting link between Meiosis-I and Meiosis-II is interkinesis.

22. Answer:  (d) Flower bud

Explanation: Diakinesis is the stage of meiosis. For the study of meiosis young flower bud is the best material.

23. Answer:  (b) root tip

Explanation: Root tips are the best to study mitosis. It is characteristic of meristematic cells present at the tip of the roots that provide the most suitable and sufficient raw material to study the different mitosis stages. Onion is a monocot plant and is the most commonly used root tip to study mitosis.

24. Answer:  (d) prophase I

Explanation:  In prophase I of meiosis, the homologous chromosomes form the tetrads.

25. Answer:  (b) 63

Explanation: Since the cells of the aleurone layer are triploid, the number of chromosomes would be = 63, as root tip cells (2n) have 42 chromosomes.

Click here to practice Cell Cycle and Cell Division MCQ Questions for Class 11

24 hours is average duration.

24 hours is the average cell cycle for mammalian cell. 

24 hours is the average cell cycle span for a mammalian cell.

Telophase nucleolus reappear during mitosis.

Three events responsible for gametic consequences during meiosis are: 

(i) The pairing of the homologous chromosomes 

(ii) The process of crossing over and recombination, and 

(iii) The segregation of homologous chromosomes.

Quiescent Stage (G₀): Cells which do not divide further, exit G₁ phase to enter an inactive stage. This stage is called quiescent stage (G₀) of the cell cycle. The cells in this stage remain metabolically active but do not undergo division. But these cells can resume division as and when required.

The sequence of events by which a cell duplicates its genome, synthesis the other constituents of the cell and eventually divides into two daughter cells.

Asters and spindle fibers are collectively called mitotic apparatus.

During ‘S’ phase in animal cells, DNA replication begins in the nucleus, and the centriole duplicates in the cytoplasm.

• Mitosis is seen in somatic cells, whereas Meiosis is seen in germ cells. 
• Mitosis is an equational division, whereas Meiosis is a reductional division.
• In mitosis no crossing over, whereas in miosis crossing over between nonsister chromatids is seen.
• In mitosis one cell produces two cells with same chromosome number, whereas In meiosis one cell produces four haploid cells

Metaphase all division to study the chromosome morphology.

Cell cycle : The sequence of events by which a cell duplicates its genome, synthesis the other constituents of the cell and eventually divides into two daughter cells. 

Phases of cell cycle : 

Interphase : 

• G₁ Phase : Cell metabolically active and grows continuously. 

• S Phase : DNA synthesis occurs, DNA content increases from 2C to 4C. but the number of chromosomes remains some (2N). 

• G₂ Phase : Proteins are synthesised in preparation for mitosis while cell growth continues. 

The division of nucleus is called karyokinesis. 

The nondividing phase of cell is interphase

(b) Synapsis

The sequence of events by which a cell duplicates its genome, synthesis the other constituents of the cell and eventually divides into two daughter cells is termed as cell cycle.

Factors controlling cell division are: 

(i) Cell size: Cells capable of division attain a particular size and then undergo division. 

(ii) Karyoplasmic ratio: Rise in cell volume disturbs karyoplasmic ratio. It stimulates the cell to divide. 

(iii) Mitogens: Mitogens, are agents, factors or substances that trigger cell division.

The formation of the new cell wall begins with the formation of a simple precursor, called the cell plate that represents the middle lamella between the walls of two adjacent cells.

The specialized kind of cell division that reduces the chromosome member by half resulting in the production of haploid daughter cells is called meiosis.

The beginning of diplotene is recognised by the dissolution of the synaptonemal complex and the tendency of the recombined homologous chromosomes to separate from each other.

Nucleosome is basic structural unit of DNA. Each strand of DNA winds around a core of eight histone molecules. This core can be imagined like a football, around which a long rope is wound with one or two loops. Each such complex structure is called a nucleosome. A single human chromosome may have about a million nucleosomes.

Gene is a structural and functional unit of heredity and variations. Genes are specific sequences of nucleotides on a chromosome that encode particular proteins which express in the form of some particular feature of the body. In other words, gene is the DNA segment of the chromosome and it controls the expression of characteristics.

Two significance of mitosis are: 

(i) Mitosis is essential for growth and development of multicellular organisms. 

(ii) Mitosis is the method of multiplication of unicellular organisms.

It takes place both in somatic and reproductive cells of the plants and animals. In multicellular organisms, mitosis produces more cells for growth and repair. Mitosis division is responsible for growth and development of a single-celled zygote into a multicellular organism. Mitosis division helps in maintaining the proper size. Mitosis also helps in restoring wear and tear in body tissues, replacing damaged or lost part, healing wounds and regeneration of detached parts.

• In multicellular organisms, growth of the body is due to mitotic division of cells.
• Replacement of worn-out cells and repair of the damaged cells is by mitosis.
• In unicellular organisms, mitosis results in asexual reproduction of cells.
• In plants, vegetative propagation involves only mitotic divisions.

Amitosis is called direct cell division.

The alignment of chromosome into compact group at the equator of the cell is known as metaphase plate.

Kinetochore is a DNA – Protein complex present in the centromere DNA, where the microtubules are attached. It is a trilaminar disc like plate.

It is an imaginary plane perpendicular to the spindle fibers of a dividing cell, along which chromosomes align during metaphase.

1. Telophase.

2. Metaphase

3. Anaphase

4. Prophase 

5. Prophase.

In some organisms karyokinesis is not followed by cytokinesis as a result of which multinucleate condition arises leading to the formation of syncytium.

E.g: liquid endosperm in coconut.

The regions where segments of non sister chromatids of the bivalents are exchanged are called chiasmata.

During diakinesis there is terminalisation of chiasmata. The chromosomes are fully condensed and the meiotic spindle is assembled to prepare the homologous chromosomes for separation. The nucleolus disappears and the nuclear envelope breaks down.

• Spindle fibres attach to kinetochores of chromosomes
• Chromosomes are moved to spindle equator and get aligned along with metaphase plate through spindle fibres to both poles.

The series of events occurring in a growing cell that occurs between the formation of cell and its division into daughter cells is called cell cycle. Two main stages are Interphase and M. Phase. 

In animal cell the centrioles extend a radial array of microtubules towards the plasma membrane when they reach the poles of the cell. This arrangement of microtubules is called an aster. Plant cells do not form asters.

The checkpoint called the restriction point at the end of G₁ it determines a cells fate whether it will continue in the cell cycle and divide or enter a stage called G₀ as a quiescent stage and probably as specified cell or die.

Mitosis is divided into four stages prophase, metaphase, anaphase and telophase.

Maturation Promoting Factor (MPF) brings about condensation of interphase chromosomes into the mitotic form.

The disadvantages of Amitosis:

• Causes unequal distribution of chromosomes. 
• Can lead to abnormalities in metabolism and reproduction.

Exact copy of the parent cell is produced by mitosis (genetically identical)

1. Genetic stability – daughter cells are genetically identical to parent cells. 

2. Repair of tissues – damaged cells must be replaced by identical new cells by mitosis. 

3. Regeneration – Arms of star fish.