Haploids are more suitable for mutation studies than the diploids. This is because
(1) haploids are reproductively more stable than diploids
(2) mutagenes penetrate in haploids more effectively than is diploids
(3) haploids are more abundant in nature than diploids
(4) all mutations, whether dominant or recessive are expressed in haploids
Telomere repetitive DNA sequences control the function of eukaryotic chromosomes because they:
(1) act as replicons
(2) are RNA transcription initiator
(3) help chromosome pairing
(4) prevent chromosome loss
Molecular basis of organ differentiation depends on the modulation in transcription by:
(1) RNA polymerase
(2) ribosome
(3) transcription factor
(4) anticodon
The length of DNA molecule greatly exceeds the dimensions of the nucleus in eukaryotic cells. How is this DNA accommodated?
(1) Deletion of non essential genes
(2) Super-coiling in nucleosomes
(3) DNAse digestion
(4) Through elimination of repetitive DNA
During transcription RNA polymerase holoenzyme binds to a gene promoter and assumes a saddle-like structure. What is it’s DNA-binding sequence?
(1) TTAA
(2) AATT
(3) CACC
(4) TATA
Differentiation of organs and tissues in a developing organism, is associated with:
(1) developmental mutations
(2) differential expression of genes
(3) lethal mutations
(4) deletion of gens
The Okazaki fragments in DNA chain growth:
(1) result in transcription
(2) polymerize in the 3’-to-5’ direction and forms replication fork
(3) prove semi-conservative nature of DNA replication
(4) polymerize in the 5’-to-3’ direction and explain 3’-to-5’ DNA replication
The two polynucleotide chains in DNA are:
(1) parallel
(2) discontinuous
(3) antiparallel
(4) semiconservative
One gene-one enzyme relationship was established for the first time in:
(1) Neurospora crassa
(2) Salmonella typhimurium
(3) Escherichia coli
(4) Diplococcus pneumoniae
A sequential expression of a set of human genes occurs when a steroid molecule binds to
the:
1. transfer RNA
2. messenger RNA
3. DNA sequence
4. ribosome