Zoology
Which of the following statements is true?
A.
Usually division of nucleus is followed by division of cytoplasm
B.
Usually Karyokinesis is followed by cytokinesis
C.
Sometime cytokinesis does not follow the Karyokinesis and results into the multinucleate cells
D.
All of these
The division of nucleus is termed as:
A.
Nucleolysis
B.
Karyotheca
C.
Karyoplasm
D.
Karyokinesis
Synaptonemal complex is associated with:
A.
Polytene chromosome
B.
Lampbrush chromosome
C.
Mitotic chromosome
D.
Paired meiotic chromosome
Before cell division, the entire DNA content of the cells gets doubled during:
A.
G1 phase
B.
S phase
C.
S2 phase
D.
M phase
The enzyme Peptidyl transferase which helps in the formation of peptide bond is present in the:
A.
t-RNA
B.
Larger subunit of the ribosome
C.
Smaller subunit of the ribosome
D.
m-RNA
The correct sequence of enzymes taking part in mechanism of protein synthesis is:
A.
RNA polymerase, sigma factor, AA t-RNA synthetase enzyme, AA activating enzyme
B.
Sigma factor, RNA polymerase, AA activating enzyme, AA t-RNA-synthetase enzyme
C.
RNA polymerase, AA activating enzyme, AA t-RNA-synthetase enzyme, sigma factor
D.
Sigma factor, RNA polymerase, AA t-RNA-synthetase enzyme, AA activating enzyme
The DNA code for the amino acid valine are CAA, CAG, CAT, CAC. What will be the mRNA transcription codes for the same amino acid?
A.
GUU, GUC, GUA, GUG
B.
GUC, GUA, GUC, AUG
C.
GTT, GTC, GTA, GTG
D.
GTA, GCA, GTG, GUC
In embryonic cells, genetic apparatus starts functioning only after organogenesis. Therefore, in early stages of cleavage when there is no mRNA, the process of protein synthesis is governed by:
A.
Infrosomes
B.
t-RNA
C.
Nucleolar organizer
D.
None of these
Heteroduplex DNA contains:
A.
Heterologous base sequence
B.
Heterozygous base sequence
C.
Homozygous base sequence
D.
Hybridized base sequence
The phenomenon of transferring characters of one strain to another by using a DNA extract of former is known as:
A.
Transformation
B.
Transduction
C.
Hybridization
D.
None of these
The function of Lampbrush chromosome are:
A.
Synthesis of RNA
B.
Formation of yolk material
C.
Synthesis of ribosomes
D.
Both (a) and (b)
The chromosome number in normal human male is:
A.
48
B.
45 autosomes + one Y (sex chromosome)
C.
22 pairs + X + Y
D.
21 pairs autosomes + 2 pairs sexchromosomes
The chromonema of the polytene gives out many series of the loops literally known as:
A.
Balbiani rings
B.
Puffs
C.
Lateral loops
D.
Folded fibre
The chromosomal segments do not fuse with each other due to polarity at their extreme ends which are known as:
A.
Dicentric
B.
Telomere
C.
Satellite
D.
Chromomere
Arrangement of genes on a chromosome is:
A.
Linear
B.
Circular
C.
Helical
D.
Spiral
Which one is cytoplasmic and self replicating among the following?
A.
Linked genes
B.
Operator genes
C.
Mitochondrial DNA
D.
Co-dominant genes
Meiosis involves:
A.
Two nuclear divisions with chromosome also dividing twice
B.
Two nuclear divisions with chromosomes dividing four times
C.
One nuclear division with chromosomes dividing only once
D.
Two nuclear divisions with chromosomes dividing only once
Which among the following does not grow and reproduce all the time?
A.
Blood forming cells of bone marrow
B.
Germinal layers of skin
C.
Epithelium of gut
D.
Striated muscle cell
The complex of microtubules connecting the two centrioles along with the centrioles is called:
A.
Spindle
B.
Mitotic apparatus
C.
Synaptonemal complex
D.
Mitotic complex
Shortly before mitosis is to take place, the two pairs of centrioles begin to move apart from each other due to:
A.
Repulsion between them
B.
Successive polymerization of proteins of microtubules
C.
Successive condensation of proteins of microtubules
D.
Contraction of microtubules
During interphase of mitosis, which other organelles along with DNA is replicated?
A.
RNA
B.
Centriole
C.
Nucleolus
D.
Mitochondria
The transcription process in DNA almost never makes a mistake. If a mistake is made in making of DNA nucleotides, it causes:
A.
Mutation
B.
Destruction of nucleus
C.
Chromosomal variation
D.
None of these
Which of the following causes bonding of the successive nucleotides to each other using phosphate bonds in newly formed DNA strand?
A.
DNA polymerase
B.
DNA ligase
C.
Endonuclease
D.
Hydrolase
Pleiotropy is:
A.
The ability of a number of genes to influence a specific character
B.
The ability of a gene to enhance the effect of another gene
C.
The ability of a gene to influence more than one character
D.
The ability of two genes to produce an intermediate effect by co-influencing a character
Which of the following examples explains the 'one gene one polypeptide' theory?
A.
Alcaptonuria
B.
Phenylketonuria
C.
Sickle cell anaemia
D.
All of these