NEET BIOLOGY

CELL STRUCTURES AND FUNCTION

CELL DIVISION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which of the following stages contains no trace of nuclear membrane?
A
Prophase 1
B
Telophase 2
C
Anaphase 1
D
Prophase 2
Explanation: 

Detailed explanation-1: -The nuclear membrane is thus absent during prophase, metaphase, and telophase. The nuclear membrane is present (and essential) during all periods of interphase. The main functions of interphase are the synthesis of cellular proteins, DNA replication, and cellular growth.

Detailed explanation-2: -During anaphase the sister chromatids are pulled apart by the mitotic spindle and move to opposite ends of the cell. The nuclear membrane begins to break down at the very end prophase and is completely deteriorated during metaphase, when the chromosomes align.

Detailed explanation-3: -The splitting of centromere does not occur in anaphase I but occurs in anaphase II. Anaphase is the stage of mitosis or meiosis when chromosomes are split and the sister chromatids move to opposite poles of the cell.

Detailed explanation-4: -Anaphase I begins when homologous chromosomes separate. The nuclear envelope reforms and nucleoli reappear. The chromosomes coil up, the nuclear membrane begins to disintegrate, and the centrosomes begin moving apart. Spindle fibers form and sister chromatids align to the equator of the cell.

Detailed explanation-5: -Nuclear membrane disappears in late prophase. Longest phase of mitosis is prophase.

There is 1 question to complete.