Multiple Choice QuestionsDuring which phase (s0 of the cell cycle, the amount of DNA in a cell remains at the 4C level if the initial amount is denoted as 2C?
Go and G1
G1 and S
Only G2
Only G2
In human females, meiosis-II is not completed until?
puberty
fertilization
uterine implantation
uterine implantation
During gamete formation, the enzyme recombinase participates during
metaphase - I
anaphase-II
prophase-I
prophase-I
In S - phase of the cell cycle
amount of DNA dobles in each cell
amount of DNA remains same in each cell
chromosome number is increased
chromosome number is increased
Given below is the representation of a certain event at a particular stage of a type of cell division. Which is this stage?
Prophase-I during meiosis
Prophase-II during meiosis
Prophase of mitosis
Prophase of mitosis
Identify the meiotic stage in which the homologous chromosomes separate while the sister chromatids remain associated at their centromeres
metaphase I
metaphase II
anaphase I
anaphase I
A somatic cell that has just completed the S phase of its cell cycle, as compared to gamete of the same species, has
twice the number of chromosomes and four times the amount of DNA
same number of chromosomes but twice the amount of DNA
twice the number of chromosomes and four times the amount of DNA
twice the number of chromosomes and four times the amount of DNA
C.
twice the number of chromosomes and four times the amount of DNA
In general a gamete contains 'n' number of chromosomes (haploid) and 'x' amount of DNA. In comparison to the gamete, an (diploid) somatic cell usually have 2n number of chromosomes and 2x amount of DNA. But, after the cell enters and complete the 'S'-phase of its cell cycle, the DNA content of the cell becomes double (due to its duplication). However, the number of chromosomes remains the same. Hence, the somatic cell that has undergone and completed its 'S' phase of cell cycle will have twice the number of chromosomes and four times the DNA content.
| Chromosomes | DNA content | |
| Gamete | n | x |
| Somatic cell (diploid) | 2n | 2x |
| Somatic cell (after S-phase) | 2n | 4x |
What would be the number of chromosomes of the aleurone cells of a plant with 42 chromosomes in its root tip cells?
63
84
21
21
Select the correct option with respect to mitosis
Chromatids start endoplasmic
Golgi complex and endoplasmic reticulum are still visible at the end of prophase
chromosomes move to the spindle equator and get aligned along equatorial plate in metaphase
chromosomes move to the spindle equator and get aligned along equatorial plate in metaphase
At metaphase, chromosomes are attached to the spindle fibres by their
satellites
Secondary constrictions
Kinetochores
Kinetochores
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