BBYET-141 · June 2025 · English
IGNOU BBYET-141 June 2025 Previous Year Question Paper
Cell And Molecular Biology
Structured previous year question paper for BBYET-141, June 2025 session.
Max marks: 50 · Questions: 8
Verified: 29 Jul 2026
BACHELOR OF SCIENCE (B. SC.)
(UGC) (CBCS)
Term-End Examination
June, 2025
BBYET-141 : CELL AND
MOLECULAR BIOLOGY
Time : 2 Hours Maximum Marks : 50
Note : Question No. 1 is compulsory. Marks are
indicated against each question. Answer
any four questions from Question Nos. 2
to 8.
Q1.(a) Fill in the blanks with the correct option given in the parentheses: 1x5=5
(6) A microscope having more than one lens is called simple/ compound) microscope. Gi) In... «(density gradient/ differential) centrifugation the molecules present in a heterogeneous mixture settle down or get sedimented under a centrifugal force or under the influence of gravity. dii) A DNA structure in which two strands can be separated is defined as (paranemic/plectonemic).
(iv) The (DNA/RNA) replication in eukaryotes occurs in a semi- conservative manner.
(v) Most bacteria are free-living organisms that grow by increasing mass and then divide by (binary/ multiple) fission.
(b) Define the following terms : 12858 G@) Homeostasis
(ii) Gene Knockdown
(ii) Inducer
(c) State whether the following statements are True (T) or False
(F) : ; x4=2
(i) The initiation of translation in eukaryotes is more complicated than prokaryotes and requires at least 12 initiation factors. Gi) In eukaryotic cells, the initiation codon AUG encodes a modified type of methionine, N-formyl- methionine.
(ii) Microtubules assist in maintaining cell shape and structure along with positioning of organelles within the cell.
(iv) Cilia are cellular appendages that help in mobility of cell in higher plants.
Q2.Describe the basic components of an electron microscope and distinguish between trans- mission and scanning electron microscopy. 4+6=
(10)
Q3.Describe different types of electrophoresis and their application in separation of biomolecules.
Q4.Discuss semi-autonomous nature of mitochondria with an emphasis on protein synthesis within mitochondria, mitochondrial DNA and marker enzymes. 3+7=
(10)
Q5.Discuss the different aspects of cell cyele regulation.
Q6.Discuss the process of DNA replication in prokaryotes.
Q7.Describe the process of translation in eukaryotes.
Q8.Write short notes on any two of the following : 2x5=10
(a) Gene regulation by chromatin modification
(b) Ribonucleic Acid (RNA)
(c) Organization of DNA in eukaryotes
(d) Genetic Code 3494-52 2x5=
(10)