GkSeries.com

Chromosomal Aberrations MCQs | Chromosomal Aberrations Multiple Choice Questions and Answers

(1) Which of the following is not true about inversion?
[A] Two DNA strands with an inverted segment will not pair
[B] Inverted chromosomes are generally viable
[C] Inversion including centromere is known as paracenric
[D] Inversion can cause chromosome breakage
Answer: Two DNA strands with an inverted segment will not pair
(2) Which of the following statement is incorrect
[A] Chromosome number is constant within different species in an ecosystem
[B] Chromosome number is constant within different somatic cells of an organism
[C] Chromosome number is constant within individuals in a species in an ecosystem
[D] All of these
Answer: Chromosome number is constant within different species in an ecosystem

DOWNLOAD CURRENT AFFAIRS PDF FROM APP

(3) The size of chromosome is measured during
[A] Metaphase
[B] Anaphase
[C] Prophase
[D] All Of These
Answer: Metaphase
(4) Euchromatin
[A] Is Partially Condensed
[B] Genetically Active Chromatin With Genes
[C] Stains Lightly
[D] All Of These
Answer: All Of These
(5) Chromatin Has
[A] DNA
[B] DNA, RNA And Proteins
[C] DNA And Proteins
[D] None Of These
Answer: DNA, RNA And Proteins
(6) A chromosome with a very short arm and a very long arm is termed as
[A] Sub-metacentric
[B] Telocentric
[C] Metacentric
[D] Acrocentric
Answer: Acrocentric
(7) ______________ inversions reduce crossing over in ______________
[A] Pericentric, Heterozygous
[B] Pericentric homozygous
[C] Paracentric, Heterozygous
[D] Paracentric, homozygous
Answer: Pericentric, Heterozygous
(8) Long pericentric inversions generally don’t act as cross over suppressors. Why?
[A] Cross over product in this is viable
[B] Two events of crossing over take place
[C] Long stretches of DNA recombination not recognized
[D] Mechanism is different for short and long inversions
Answer: Two events of crossing over take place
(9) In drosophila male there is no cross over suppression due to pericentric inversion as___________
[A] They never recombine
[B] They have only one set of chromosome
[C] They don’t undergo meiosis
[D] They always have double cross over
Answer: They never recombine
(10) How will you recognize a terminal deletion from breakage and loss at the terminal end?
[A] Terminal break will be sticky
[B] Deletion will be recognized by trans factors
[C] Indistinguishable
[D] Terminal break will lead to shorter chromosome than that due to chunk deletion
Answer: Terminal break will be sticky
(11) You hybridize two cells one of which carries a deletion mutation on chromosome 1. What will you expect to observe?
[A] Buckling of chromatin of 2nd cell
[B] Buckling of chromatin of 1st cell
[C] No observable difference
[D] Twisting and loop formation between the two chromatins
Answer: Buckling of chromatin of 2nd cell
(12) You generate a fluorescent probe against a gene that has been deleted. You expose the DNA to the probe and observe it under fluorescent microscope. What will you see?
[A] Nothing is seen under fluorescence microscope
[B] Most parts of the chromosome emits fluorescence
[C] Fluorescence will correspond to the gene of interest
[D] There will be a number of regions that emit fluorescence
Answer: Nothing is seen under fluorescence microscope
(13) Deletion of a region led to over expression of a gene X. What do you conclude from this observation?
[A] Regulator of gene X is deleted
[B] No effect on gene X or its regulators
[C] Part of gene X is mutated
[D] Promoter of gene X is deleted
Answer: Regulator of gene X is deleted
(14) Yellow colour of mouse is generated by _________ mutation.
[A] Deletion
[B] Translocation
[C] Duplication
[D] Inversion
Answer: Deletion
(15) Which of the following is not true about the Notch gene in Drosophila?
[A] Notch is lethal in homozygous form
[B] Notch is recessive to Facet
[C] It causes a special indentation of the wing margin
[D] It is expressed in heterozygous form
Answer: Notch is recessive to Facet
(16) Who coined the term ‘chromatin’ to describe the thread like material of the nucleus?
[A] Boveri
[B] W.Roux
[C] E. Strasburger
[D] W. Flemming
Answer: W. Flemming
(17) The lowest level of chromosome organization is
[A] 30nm Fibre
[B] Solenoid
[C] Nucleosome
[D] None Of These
Answer: Nucleosome
(18) Chromosome is thickest during
[A] Metaphase
[B] Interphase
[C] Prophase
[D] None Of These
Answer: Metaphase
(19) Consider this sequence A—O—B —C—D—E—F, be a DNA sequence where O is the centromere. Which of the following will be a pericentric inversion?
[A] A—O—E—D—B—F
[B] D—B—O—A—E—F
[C] A—O—B—D—E—F
[D] B—O—A—D—E—F
Answer: A—O—E—D—B—F
(20) What are the results of pericentric inversion with single crossing over?
[A] 2 dicentric and 2 acentric chromosomes
[B] 3 normal chromosome, one abnormal acentric chromosome
[C] Two normal, one dicentric and one acentric chromosome
[D] Four normal chromosomes with centriomere in different positions
Answer: Two normal, one dicentric and one acentric chromosome

Please share this page

Click Here to Read more questions

Teacher Eligibility Test