Zoology
The coiled segment of chromosomes is generally called the:
A.
Centromere
B.
Satellite
C.
Chromomeres
D.
All of these
The genetic concept of segregation and recombination are most associated with:
A.
Meiosis and fertilization
B.
Mitosis and fertilization
C.
Meiosis and mitosis
D.
None of these
The size of the nucleus in a cell is directly proportional to:
A.
The amount of DNA it contains
B.
The metabolic phase of the cell
C.
The volume of cytoplasm
D.
All of these
Barr body is found in:
A.
Ova
B.
Sperm
C.
Follicle cells
D.
Female somatic cells
Translocation is a type of chromosomal aberration where:
A.
Parts of chromosome are exchanged between homologous chromosomes
B.
A part of one chromosome is exchanged between non-homologous counterpart
C.
A part of one chromosome is shifted to its homologous counterpart
D.
A part of one chromosomes is shifted to another part of the same chromosome
Classically gene is a :
A.
Unit of mutation
B.
Unit of physiological function
C.
Unit of segregation and transmission
D.
All of these
The portion of DNA specifying a single polypeptide chain is termed as:
A.
Muton
B.
Cistron
C.
Recon
D.
None of these
The Okazaki fragments represent the:
A.
Leading strand of DNA
B.
Lagging strand of DNA
C.
Template strand of DNA
D.
None of these
During DNA replication, the sequence specificity of bases in the newly synthesized strand is determined by:
A.
DNA polymerase - I
B.
DNA polymerase - III
C.
Restriction endonuclease
D.
The template strand
The concept of a split gene is that the:
A.
DNA in a gene can be splitted by deoxyribosnuclease
B.
Coding sequence in many eukaryotic genes are often separated by non-coding sequences
C.
Secondary constriction on the chromosomes gives the split appearance to genes
D.
Adjacent genes are separated from each other by spacers
Chromatin is formed by:
A.
Single, elongated and highly folded DNA
B.
Double helical molecules of DNA
C.
DNA and RNA
D.
DNA, RNA and associated proteins
The spermatid formed during spermiogenesis contains:
A.
Golgi body, centriole and haploid set of chromosomes
B.
Golgi body, mitochondria and diploid set of chromosomes
C.
Mitochondria and diploid set of chromosomes
D.
Golgi body, centriole, mitochondria and a haploid set of chromosomes
It is formed that one chiasma formation reduces the probability of another chiasma formation in the adjacent regions of chromosomes. This tendency is called:
A.
Interference
B.
Inhibition
C.
Restitution
D.
None of these
The period between two nuclear divisions during mitosis is characterized by:
A.
Important metabolic reactions in the cytoplasm
B.
DNA replication
C.
The presence of more mitochondria
D.
The suspension of metabolic activities
Number of chromosomes of primary spermatocytes:
A.
Is double the number of chromosomes in spermatogonia
B.
Is equal to number of chromosomes in spermatogonia
C.
Is equal to the number of chromosomes in secondary spermatocytes
D.
Is half the number of chromosomes in secondary spermatocytes
50 secondary spermatocytes and 50 secondary oocytes form:
A.
200 sperm and 50 ova
B.
200 sperm and 25 ova
C.
100 sperm and 25 ova
D.
100 sperm and 50 ova
Syncytium in animals may be produced as a result of:
A.
Amitosis
B.
Mitosis
C.
Meiosis
D.
Parthenogenesis
To increase their number, the gonads and sex cells depend on:
A.
Mitosis
B.
Meiosis
C.
Amitosis
D.
Both mitosis and meiosis
What will be the sequence of mRNA molecule synthesized from a DNA template having the sequence A-T-C-G-T-A-C-C-G-T-T-A?
A.
U-A-G-C-A-U-G-G-C-A-A-U
B.
T-A-G-C-A-T-G-G-C-A-A-T
C.
A-T-C-G-A-T-U-C-G
D.
None of these
The initiation codon in protein synthesis is:
A.
AUG
B.
UGA
C.
UAG
D.
UAA
How many times mitotic divisions must occur in a cell to from 128 cells?
A.
7
B.
16
C.
32
D.
64
What is the most important morphological peculiarity of polytene chromosomes of salivary gland cell of Dorsophila?
A.
Size
B.
Length
C.
Interbands
D.
Easily observable features
During cell division, DNA duplication occurs in:
A.
Prophase
B.
G1 of interphase
C.
S- phase of interphase
D.
Early Telophase
Which one of the following statements best explains the evolutionary advantage of meiosis?
A.
Genetic recombination are possible from generation to generation
B.
Meiosis alternates with mitosis from generation to generation
C.
The same genetic system is passed on from generation to generation
D.
Meiosis I is necessary for sexual reproduction
The newly synthesized polypeptide, after being translated completely from the mRNA, is dislodged from the ribosome.
A.
Because the release of the polypeptide chain goes hand in hand with the dissociation of ribosomal subunits
B.
Due to the force generated from the folding of the primary protein molecule for constituting its secondary structure
C.
Because release factors(s) may block specific site on the ribosomal surface facilitating the release of the peptide chain
D.
Due to the synthesis of an enzyme which inactivates the peptide binding enzyme