251. Which is correct for meiotic metaphase- I
A
Bivalents are arranged at equator
B
Univalents are arranged at equator
C
Non-homologus chromosomes forms pair
D
Spindle fibers are attached at chromomere
Answer :
Bivalents are arranged at equator
252.
Given below is a schematic break-up of the phases / stages of cell cycle:
Which one of the following is the correct indication of the stage/phase in the cell cycle?
A
$$C$$ - Karyokinesis
B
$$D$$ - Synthetic phase
C
$$A$$ - Cytokinesis
D
$$B$$ - Metaphase
Answer :
$$D$$ - Synthetic phase
253. What happnes in synthesis phaseduring cell cycle
A
DNA synthesis
B
Chromosome number become double
C
Formation of two nuclei
D
Synthesis of proteins & RNA
Answer :
DNA synthesis
254. If a diploid cell is treated with colchicine then it becomes
A
triploid
B
tetraploid
C
diploid
D
monoploid
Answer :
tetraploid
255. In animals, cytokinesis is
A
Centrifugal
B
Centripetal
C
Random
D
Collateral
Answer :
Centripetal
256. In the somatic cell cycle
A
In $${G_1}$$ phase DNA content is double the amount of DNA present in the original cell
B
DNA replication takes place in $$S$$ - phase
C
a short interphase is followed by a long mitotic phase
D
$${G_2}$$ phase follows mitotic phase
Answer :
DNA replication takes place in $$S$$ - phase
257. Reappearance of nuclear membrane & nucleolus along with thing & elongation in chromosomes are diagnostic character for the phase
A
Anaphase
B
Metaphase
C
Interphase
D
Telophase
Answer :
Telophase
258. In which of the following stage chromosomes are arranged at equatorial plate
A
Anaphase
B
Metaphase
C
Prophase
D
Telophase
Answer :
Metaphase
259. In eukaryotic cell the type ribosome is
A
Only 70 s
B
Only 80 s
C
70 s and 80 s both
D
Only 50 s
Answer :
70 s and 80 s both
260. Chromosomal morphology (Structure) is best observed at
A
Prophase
B
Metaphase
C
Interphase
D
Anaphase
Answer :
Metaphase