The S-phase of cell cycle is characterized by:
duplication of chromosome
shotening of chromosome
duplication of DNA
duplicatin of centriole
C.
duplication of DNA
The cell cycle of eukaryotic cell is divided into following four phases.
(1) G1 phase (first growth phase)
(2) S phase (synthesis phase)
(3) G2- phase (second growth phase)
(4) M-phase (mitotic phase)
S-phase is the phase is cell cycle during which DNA is replicated.
Match the sub-stage of prophase I of meiosis in Column I and the events in Column II and choose the right option.
| Column I | Column II |
| A. Leptotene | 1. Terminalization of chiasma |
| B. Zygotene | 2. Crossing over and recombination |
| C. Pachytene | 3. Synapsis |
| D. Diakinesis | 4. Visibility of chromosomes |
A - 1; B - 2; C - 3; D - 4
A - 1; B - 3; C - 2; D - 4
A - 4; B - 3; C - 2; D - 1
A - 4; B - 1; C - 2; D - 3
A - 4; B - 1; C - 2; D - 3
Find out the correct statement
During mitosis endoplasmic reticulum and nucleolus disappear completely at early prophase
Chromosomes are arranged along the equator during prophase of mitosis
Chromosome is made up of two sister chromatids at anaphase of mitosis
A cell plate is laid down during interphase
A cell plate is laid down during interphase
Chiasmata are most appropriately observed in meiosis during :
diakinesis
diplotene
metaphase II
pachytene
In a typical eukaryotic cell cycle, Gap 1, Synthesis and Gap 2 are the three phases included in the
Prophase
Metaphase
Anaphase
Interphase
Interphase
Which one of the following is the significance of mitosis?
Restricted to haploid cells
Cell repair
Increases the genetic variability
Recombination of chromosomes
Recombination of chromosomes
Which of the following maintain the constant number of chromosomes generation after generation?
Meiosis
Endomitosis
Mitosis
Amitosis
