Biology

Cell Cycle and Chromosomes

1,348 Questions

Explore a curated list of questions covering the cell cycle, mitosis, and meiosis. Topics include DNA replication, chromosomal structures, and genetic disorders. This material is essential for students preparing for biology and general science competitive exams.

Cell cycle eventsDNA replicationMeiosis processChromosomal structuresGenetic disorders

Cell Cycle and Chromosomes Questions

Multiple choice bio-chemistry caskets of life animal cells vs plant cells comparing plant and animal cells comparison between animal and plant cell

Plant and animal cell divisions differ in 

  1. Cell plate

  2. Prophase

  3. Metaphase

  4. Telophase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The plant and animals are the eukaryotic cells which divide by mitotic cell division. The various stages of the mitosis are prophase, metaphase, anaphase and telophase, which are same for all the eukaryotic cells. During telophase, there is the formation of the cell plate in case of plant cells which allows the separation of the two daughter cells. In the case of animal cells, there is pinching of the cell membrane to separate the cells. Thus, the correct answer is option A. 

Multiple choice bio-chemistry caskets of life animal cells vs plant cells comparing plant and animal cells comparison between animal and plant cell

In a plant cell, cytokinesis occurs by

  1. Separation of the cytoplasm from the periphery to central region

  2. Separation of the cytoplasm from cell centre to its periphery

  3. Separation of the cytoplasm throughout the equatorial plane simultaneously

  4. Furrowing of cytoplasm from two sides at right angles to the plane of spindle pole
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In plant cells, cytokinesis involves the formation of a cell plate that starts at the center of the cell and grows outward toward the periphery, eventually fusing with the existing cell wall.

Multiple choice biology organization of life comparison of prokaryotic vs eukaryotic cells prokaryotic cell and eukaryotic cell types of cell

Eukaryotic chromosome different from prokaryotic as these are made up of

  1. RNA

  2. DNA

  3. DNA and lipid

  4. DNA and histone
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Eukaryotic chromosomes are made of chromatin, a nucleoprotein - DNA coiled around histone proteins while prokaryotic chromosomes are circular chromosome attached to the inside of the cell membrane. They are single chromosome plus plasmids

Multiple choice biology organization of life comparison of prokaryotic vs eukaryotic cells prokaryotic cell and eukaryotic cell types of cell

In eukaryotic cell,

  1. A spindle apparatus is produced during nuclear division.

  2. A spindle apparatus is not formed during division.

  3. Gametes are not formed

  4. Ribosomes are of 70S type
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The spindle apparatus (or mitotic spindle) refers to the cytoskeletal structure of eukaryotic cells that forms during cell division to separate sister chromatids between daughter cells. It is referred to as the mitotic spindle during mitosis, a process that produces genetically identical daughter cells, or the meiotic spindle during meiosis, a process that produces gametes with half the number of chromosomes of the parent cell.

So, the correct answer is 'A'.
Multiple choice biology organization of life comparison of prokaryotic vs eukaryotic cells prokaryotic cell and eukaryotic cell types of cell

Lowest number of chromosomes is found in

  1. Radiolaria

  2. Amoeba

  3. Ascaris meglocephala

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ascaris meglocephala (horse round worm ) has chromosome number 2n = 2. 

Amoeba has chromosome number 2n = 12. 
The maximum numbers of chromosomes is found in a protozoan (Radiolarian), where total number of chromosomes are 1600 i.e. 2n = 1600.

Multiple choice sexual reproduction in flowering plants reproduction - the generating system reproduction sexual reproduction biology reproductive health of humans need of family planning reproductive health problems cell division in embryo development division for growth and reproduction reproductive health

If the diploid number of an angiospermic plant  is 24, the number of chromosomes in the pollen grain, endosperm and integument will be 

  1. 12, 36, 12

  2. 12, 24, 36

  3. 12, 12, 36

  4. 12, 36, 24
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

12, 36, 24; because pollen grains are haploid while endosperm has triploid chromosome number and integument is diploid in nature.

Multiple choice sexual reproduction in flowering plants reproduction - the generating system reproduction sexual reproduction biology reproductive health of humans need of family planning reproductive health problems cell division in embryo development division for growth and reproduction reproductive health

Root of flowering plant has $24$ chromosomes. Its gamete would carry chromosomes.

  1. $4$
  2. $8$
  3. $12$
  4. $24$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The root of a flowering plant is diploid (2n = 24). Gametes are haploid (n), so they contain half the number of chromosomes, which is 12.

Multiple choice sexual reproduction in flowering plants reproduction - the generating system reproduction sexual reproduction biology reproductive health of humans need of family planning reproductive health problems cell division in embryo development division for growth and reproduction reproductive health

Number of chromosomes is $24$ in nucellus. Number of chromosomes in microspore mother cell would be.

  1. $36$
  2. $30$
  3. $24$
  4. $12$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The nucellus is a diploid tissue (2n). The microspore mother cell (MMC) is also a diploid cell derived from the sporophytic tissue, so it has the same chromosome number.

Multiple choice sexual reproduction in flowering plants reproduction - the generating system reproduction sexual reproduction biology reproductive health of humans need of family planning reproductive health problems cell division in embryo development division for growth and reproduction reproductive health

Number of chromosomes in root cell is $14$. What will be chromosome number in synergids.

  1. $14$
  2. $21$
  3. $7$
  4. $28$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Root cells are diploid (2n = 14). Synergids are part of the embryo sac and are haploid (n). Thus, n = 7.

Multiple choice biology anatomy of flowering plants theories of meristematic cell development theories of shoot apical meristem development shoot and root apex

Quiescent centre is the zone of

  1. Least mitotic activity in the root apex

  2. Least mitotic activity in the shoot apex

  3. Maximum mitotic activity in the root apex

  4. Maximum mitotic activity in the shoot apex
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A zone of inactive cells is present in the central part of the root apex called quiescent centre.

Multiple choice zoology applications of biotechnology genetically engineered insulin application of biology in therapy and vaccine application of biotechnology in medicine

Which one of correct?

  1. Centromere is found in animal cells which produces aster during cell division

  2. Insulin gene is present in every body cell

  3. Nucleosome is formed of nucleotides

  4. DNA has a core of eight histones
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Every somatic cell in the human body contains the complete genome, including the gene for insulin, although it is only expressed in the beta cells of the pancreas.

Multiple choice biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

Which of the following stage of M-phase is considered as tetraploid stage?

  1. Anaphase of mitosis

  2. Anaphase-I of meiosis

  3. Metaphase-II of meiosis

  4. More than one option is correct
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In mitosis DNA content is doubled during S phase resulting in 2n chromosomes having two chromatids. These 2 chromatids of 2n get arranged at metaphase plate in metaphase. And in anaphase, the 2 chromatids of 2n chromosomes are separated from each other . so the cell during this phase becomes 4n.

So, the correct answer is 'Anaphase of mitosis'.