GATE Biotechnology Previous Questions and Answers

31. Multiplication of genetically identical copies of a cultivar by asexual reproduction is known as

(a) aclonal propagation
(b) clonal propagaation
(c) polyclonal propagation
(d) vegetative propagation

Ans: clonal propagaation

32. Parthenogenetic embryos in plant are those are formed by

(a) unfertilized eggs
(b) fertilized eggs
(c) male gametophyte
(d) sporophytic cells

Ans: unfertilized eggs

• Parthenogenesis: The development of an individual from an egg without fertilization.

33. Which one of the following is the growth factor used for growth of tissues and organs in plant tissue culturee?

(a) Cytokinin
(b) Cysteine
(c) Cytidylate
(d) Cyclic AMP

Ans: Cytokinin

• Cysteine :Sulphur containing amino acid
  
• Cytidylate: an enzyme with kinase activity
  
• Cyclic AMP: second messenger in intracellular signal transduction
  

34. Which of the following techniques is best suited for immobilizing an affinity ligand?

(a) Physical adsorption
(b) Gel entrapment
(c) Cross-linking with a polymer
(d) Covalent linkage to a spacer arm

Ans: Covalent linkage to a spacer arm

35.  To be a cloning vector, a plasmid does NOT require

a) an origin of replication
b) a restriction site
c) an antibiotic resistance marker
d) to have a high copy number

Ans: d) to have a high copy number
Properties of a Cloning Vector

• Should be able to replicate autonomously
  
• Easy to transform
  
• Should have suitable marker
  
• Unique restriction sites
  
• For expression vector, control elements like promoter, operator etc should be there.

36. Enzyme papain is used with success to

a) increase in meat production
b) leaven bread
c) ripen papaya fruit
d) tenderize meat

Ans: d) tenderize meat

• Source: papaya fruit

37. For protoplast fusion to be successful in plant cells

a) fusion agents other than polyethylene glycol should be used
b) cellwall of the two strains of cells should be compatible
c) DNA between the two cells should be compatible
d) osmolarity of the medium is not important

Ans: DNA between the two cells should be compatible

38. In animal cell culture, the addition of serum to media is essential for providing

a) amino acids for protein synthesis
b) nucleotides for DNA synthesis
c) growth factors
d) All of the above

Ans: All of the above

39. Which one of the following reactions is used for the purpose of recycling enzymes in bioprocesses?

a) isomerisation
b) immobilisation
c) phosphorylation
d) polymerisation

Ans: Immobilisation

• Technique used for the fixation of enzymes or cells on to solid supports
  
• Advantage: reuse of enzyme for many reactions
  
• Methods of enzyme immobilization:-adsorption, covalent bonding, entrapment, membrane confinement.

40. The most widely used program for multiple sequence alignment is

a) FASTA
b) BLAST
c) RASMOL
d) CLUSTAL
Ans: d) CLUSTAL