31. Which of the following structure is not surrounded by one or more membrane?
a)Chloroplast
b)mitochondria
c)peroxisome
d)ribosome
Ans: d)ribosome
Refer: Cell structure and Function
32. Cot ½ of DNA is defined as
a)the time taken to reanneal
b)
concentration of DNA in a cell at any time
c)
amount of cytosine bases in a single strand by DNA
d)the
initial concentration multiplied by time for half of DNA to reanneal
Ans: d)the initial concentration multiplied
by time for half of DNA to reanneal
33.Chaperon protein help in
a) protein folding and assembly
b)
protein folding only
c)
protein stability
d)
both a and b
Ans: d) both a
and b
34. An enzyme responsible for the
synthesis of tRNA
a) tRNA replicase
b) tRNA synthetase
c)ribosomal enzymes
d)RNA polymerase
Ans: d)RNA
polymerase
35. Polytene chromosomes is generated
by
a)DNA
replication failure
b)Homologous
chromosome pairing
c)
Transcription Process
d)DNA
replication without segregation
Ans: d)DNA replication without segregation
Refer: Giant Chromosomes
36. Which of the following correctly
matches a phase of the cell cycle?
a) S1
immediately precedes cell division
b)
G2, Cell division
c)M1,
Duplication of DNA
d)G1 immediately
follows cell division
Ans: d)G1 immediately follows cell division
Refer: Cell cycle
37. The ‘RNA world hypothesis’
proposes that
a)
RNA formed from DNA
b)RNA
is catalyst
c)
RNA formed from protein
d)
RNA is both catalyst and genetic material
Ans: d) RNA is both catalyst and genetic
material
38. Replication in DNA moves from
a)3’ to 5’ direction
b) 5’ to 3’ direction
c)3’ to 3’ direction
d)5’ to 5’ direction
Ans: b) 5’ to 3’ direction
Refer: Replication in DNA
39. Choose the more appropriate term
for Connexin protein
a)
Desmosome
b)intercellular
spces
c)tight
junction
d)Gap
junctions
Ans: d)Gap
junctions