Tag: nucleus and chromosome

Questions Related to nucleus and chromosome

During cell division, spindle fibers attach to which part of chromosomes?

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Primary constriction

  2. Secondary constriction

  3. Chromomere

  4. Chromatid

Show answer
Correct Option: A
Explanation:

During cell division, spindle fibers attach to primary constriction of the chromosomes. Spindle fibres are mainly composed of microtubules which contract and relax to align the chromosomes at a particular orientation.

So, the correct answer is option A.

Bead like thickened portions of leptotene chromosomes are 

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Centromeres

  2. Chromomeres

  3. Centrioles

  4. Chromocenters

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Correct Option: B
Explanation:

Bead-like thickened portions of leptotene chromosomes is chromomeres. During the leptotene stage, those duplicated chromosomes each consisting of two sister chromatids condense from diffuse chromatin into long, thin strands that are more visible within the cytoplasm.

So, the correct answer is option B.

Most of the DNA of living beings is present in the 

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Cytosome

  2. Nucleosome

  3. Chromosme

  4. Protosome

Show answer
Correct Option: C
Explanation:

A chromosome is composed of DNA and proteins. DNA are the hereditary units which mainly carries the information from one generation to the other. The functional segments of the DNA are known as genes. Proteins are mainly present as histones which form a complex structure known as a nucleosome.

So, the correct answer is option C.

Apart from sex chromosome, which is the other type of chromosome?

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Autosome

  2. Cytosome

  3. Both A and B

  4. Protosome

Show answer
Correct Option: A
Explanation:

Chromosomes in humans can be divided into two types, autosomes, and sex chromosome. The sex chromosomes carry the characters linked to a particular trait. The autosomes contain the rest of the genetic hereditary information. Human cells have 23 pairs of chromosomes (22 pairs of autosomes and one pair of sex chromosomes), giving a total of 46 per cell.

So, the correct answer is option A. 

.......... gives chromosome its characteristic shape.

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Centrosome

  2. Centromere

  3. Centriole

  4. P-arm

Show answer
Correct Option: B
Explanation:
A chromosome is composed of DNA and proteins. DNA are the hereditary units which mainly carries the information from one generation to the other. The functional segments of the DNA are known as genes. Proteins are mainly present as histones which form a complex structure known as a nucleosome.
Each chromosome has a point where sister chromatids attached and give shape to the chromosome, called as the centromere, which divides the chromosome into two sections, or arms. It can be used to describe the location of specific genes. 
So, the correct answer is option B.

By which chromosomes are made of?

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. DNA and RNA

  2. DNA and proteins

  3. DNA only

  4. Proteins only

Show answer
Correct Option: B
Explanation:
  • Chromosomes are thread-like structures located inside the nucleus of animal and plant cells.
  •  Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from parents to offspring, DNA contains the specific instructions that make each type of living creature unique.

Chromosomes contain information for inheritance of features from parents to next generation in the form of 

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. DNA

  2. RNA

  3. Proteins

  4. Chromatin

Show answer
Correct Option: A
Explanation:

Chromosomes are composed of DNA and proteins. DNA molecules contain the information necessary for constructing and organizing the cells. Functional segments of DNA are called as genes. In a cell, which is not dividing, this DNA is present as part of a chromatin material. Whenever the cell is about to divide, the chromatin material gets organized into chromosomes and transferred  to the next generation.

So, the correct answer is option A.

Chromosome carry .......... which helps in the inheritance or transfer of characters from the parents to the offspring.

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Genes

  2. Enzymes

  3. RNA

  4. None of the above

Show answer
Correct Option: A
Explanation:

The nucleus of a cell contains chromosomes, which carry genetic information in a long molecule called as DNA. Genes are regions of DNA that carry the code to control a particular cell activity or the production of a particular protein.

So, the correct answer is option A.

The sex chromosomes of plants were first discovered in

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Algae

  2. Fungi

  3. Pteridophyta

  4. Flowering plants

Show answer
Correct Option: D
Explanation:

Sex determination method is well understood in animals but not in plants. Plants may be monoecious or dioecious but the mechanism of sex differentiation was not well understood. It now appears that at least higher or flowering plants may be having sex determination mechanism based on sex chromosomes like animals, as humans which have XX and XY system of sex determination.

So, the correct answer is option D.

Eukaryotic chromosomes always exist

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. In pairs

  2. In association with mitochondria

  3. Singly

  4. None of the above

Show answer
Correct Option: D
Explanation:

Let's take Human somatic cell as an example for the typical eukaryotic cell.

The Human somatic cell is diploid that means the chromosomes exists in double number. 
And these chromosomes in the eukaryotic cell are located in the nucleus and no where associated with mitochondria.
The human somatic cell has 23 pairs of chromosomes but there are 24 types of chromosomes because X and Y chromosomes which are called as sex chromosomes were structurally not similar. 
The remaining 22 types of chromosomes exists in pairs which are homologous (structurally relative) with their pairs.
Hence, all the chromosomes doesn't exist in pairs.
And during the cell division process the homologous chromosomes were separated to opposite poles and therefore doesn't always exists in pairs.
And they also don't exist always in single.