Biology Today — January 2018

(Jacob Rumans) #1
Figure Based Questions


  1. Consider the given cross and answer the following
    questions.


XXh × XY


Mother Father
Parents:

Gametes:

Offspring:

X

XY XXh XX XhY

Xh X Y

(a) Identify the type of disease depicted by the given
cross. Also name the type of inheritance shown.
(b) In the given cross, what would be the probability of
having a carrier and diseased offspring?
(c) Name any other disease, which shows same type of
inheritance pattern.


  1. Refer to the given figure and answer the following


questions.

(a) Identify the types of chromosomal aberration labelled
as W, X, Y and Z in the given figure.
(b) Briefly describe aberration labelled as W and Y in the
given figure.
(c) Which of the labelled chromosomal aberration(s)
represent interchromosomal aberration?

CHAPTER-6 : MOLECULAR BASIS OF INHERITANCE
Multiple Choice Questions


  1. Which of the following observations of Hershey and Chase
    experiment proved that DNA is genetic material?
    (a) The bacteriophage labelled with radioactive sulphur
    made the bacterial DNA radioactive.


(b) The bacteriophage labelled with radioactive phosphorus
did not make bacteria radioactive.
(c) Bacteriophage labelled with radioactive sulphur
made only the bacterial proteins radioactive.
(d) Bacteriophage labelled with radioactive phosphorus
made the bacterial DNA radioactive.


  1. Select the mismatched pair with reference to eukaryotic
    transcription.
    (a) RNA Pol I – Synthesises snRNA
    (b) RNA Pol II – Synthesises mRNA
    (c) RNA Pol III – Synthesises tRNA
    (d) RNA Pol III – Synthesises 5S rRNA

  2. Which of the following can be used to determine original
    source of DNA?
    (a) A/T = 1 and G/C = 1
    (b) A - T base pairs rarely equals C - G base pairs


(c)

A+T
G+C







ratio is constant for a species

(d) All of these


  1. Identify the correct sequence of DNA packaging in terms
    of ascending order of size.
    (a) DNA → Nucleosome → Chromatin fibre
    → Solenoid → Chromatid → Chromosome
    (b) DNA → Nucleosome → Chromatid → Solenoid
    → Chromatin fibre → Chromosome
    (c) DNA → Nucleosome → Solenoid → Chromatin fibre
    → Chromatid → Chromosome
    (d) DNA → Nucleosome → Solenoid → Chromatid
    → Chromosome → Chromatin fibre

  2. Which of the following events takes place during post-
    transcriptional modification in eukaryotes?
    (a) 7-methyl guanosine cap is added at 3c end of RNA
    transcript.
    (b) Addition of poly A segment at 5c end of transcript.
    (c) Exons are removed from primary transcript.
    (d) Cleavage of primary transcript by ribonuclease-P.

  3. Which DNA molecule among the following will melt at
    lowest temperature?
    (a) 5 c - A-A-T- G-C-T-G-C-3c
    3 c - T-T-A-C-G-A-C-G-5c
    (b) 5 c- A-A-T-A-A-A-G-C-T-3c
    3 c- T- T- A-T- T- T-C-G-A-5c
    (c) 5 c-G-C-A-T-A-G-C-T-3c
    3 c-C-G-T- A-T-C-G-A-5c
    (d) 5c- A-T- G- C- T- G-A-T-3c
    3 c- T- A-C-G-A- C- T- A-5c

Free download pdf