Tag: chromosome and its structure

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Questions Related to chromosome and its structure

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

which of the following is typically not found in normal somatic cells of human male?

  1. the entire genetic information possesed by the original zygote

  2. an inactivated X chromosome

  3. forty four autosomes

  4. a diploid nucleus

  5. A Y chromosomes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An inactivated X-chromosomes : female have XX chromosomes and male have XY chromosomes ,for balance Xlinked gene between male and female,one X chromosome undergo inactivated during the female embryo development this is termed as X chromosomes inactivation

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

Which of the following dyes is best suited for staining chromosomes ?

  1. Basic Fuchsin

  2. Safranin

  3. Methylene blue

  4. Carmine
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

(a) Basic Fuchsin-  It is a green crystalline dye. It includes staining of tissues sections.

(b) Safranin- It is used to stain gram-negative bacteria, mucin, etc.
(c) Methylene blue- It is used to examine DNA or RNA under the microscope.
(d) Carmine -  It is a type of stain used to stain chromosomes, nuclei etc.
So, the correct option is 'Carmine'.

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

Which of the following does not occur during condensation of chromosomes?

  1. Unfolding of protein molecules

  2. Coiling of DNA

  3. Dehydration

  4. Hydration
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Chromosome condensation is the dramatic re-organization of the long thin chromatin strands into the compact short chromosomes that occur in mitosis and meiosis. Here, the unfolding of proteins takes place, the DNA coils, dehydration takes place. However, there is no addition of water molecule or hydration that takes place during condensation.

So, the correct answer is option D.

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

Structure which provide shape to chromosome is called as

  1. Telomere

  2. Satellite

  3. Centromere

  4. Chromomere
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Centromere provides structure to the cell. The sister chromatids are linked together at the centromere. During mitosis, spindle fibers attach to the centromere via kinetochore. Their physical role is to act as the site of assembly of the kinetochore, a highly complex multiprotein structure that is responsible for the actual events of chromosome segregation, i.e., binding microtubules and send signals to the cell cycle machinery.

So, the correct answer is option C.

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

Part of chromosome after secondary constriction is called as

  1. Chromomere

  2. Telomere

  3. Satellite

  4. Nucleolar organiser
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chromosomes are the carrier of genetic information in form of DNA. The secondary constrictions are used as a point of identification of chromosomes. These are always constant in their positions and hence, can be used as markers that identify particular chromosomes. A satellite chromosome or SAT chromosome has a chromosome segment that is separated from the main body of the chromosome by such a secondary constriction.

So, the correct answer is option C.

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

General length of chromosome is

  1. 5$\mu$m - 10$\mu$m
  2. 0.2$\mu$m - 2$\mu$m
  3. 0.1$\mu$m - 30$\mu$m
  4. 0.1$\mu$m - 4$\mu$m
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chromosomes are the genetic material present in the nucleus of a cell. It is composed of DNA and protein. The functional segment of DNA is known as a gene. The size of chromosomes varies from as small as 0.1$\mu$m to as big as 15$\mu$m in length.

So, the correct answer is option C.

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

The chromosome that lacks a centromere is called as

  1. Telocentric

  2. Acentric

  3. Metacentric

  4. Acrocentric
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
In acrocentric chromosome, the centromere is present close to the end of the chromosome. Due to this one arm is very short and another arm is longer. 
In metacentric, the centromere is in the middle of the chromosome and the two arms are of equal length. 
In telocentric, the centromere is present at the end of a chromosome.
In acentric the chromosome that lacks a centromere. So, the correct answer is option C.
Multiple choice botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

The largest normal metaphasic chromosome has a size of

  1. $1\mu m$
  2. $10\mu m$
  3. $20\mu m$
  4. $30\mu m$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The largest normal metaphasic chromosome has the size of 30nm with the base of the nucleosome core particle consists of the 146 base pairs of DNA. During metaphasic state, when a chromosome in its most condensed state can range in size between 130,000 base pairs in the endosymbiotic bacteria, then the chromatin can be further condensed by coiling into 30nm in fibres.
So, the correct answer is option D.

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

During staining, chromosomes get stained with

  1. Eosine

  2. Borax carmine

  3. Acetocarmine

  4. Safranin.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

  • Stains are used in the microscopic studies of different components and organelles within a cell.
A. Eosine is stain used to stain the cytoplasm of the cell because these acidic dyes bind to basic proteins in the cytoplasm of the cell.
B. Borax carmine consists of borax, carmine and water which produces a permanent red nuclear stain which stains the nucleus and the cytoplasm.
C. Acetocarmine is a saturated solution of carmine in 45% of acetic acid which is used for staining the unfixed chromosomes within the nucleus of a cell that is used to study different stages of the chromosomes in cell division.
D. Safranin is a basic counterstain dye used in histology and cytology.

So, the correct answer is 'Acetocarmine'.

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

The term chromonema was coined by

  1. Flemming

  2. Strasburger

  3. De Robertis

  4. Vijdovsky
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Chromonema is spirally coiled central filament that extends the entire length of a chromosome and on which the genes are located. During mitotic prophase, the chromosome material appeared as thin filaments which are known as chromonema. This term is introduced by Vijdovsky in 1912. 

It represents chromatids in the early stages of condensation. Hence option D is correct.