What must occur for a secondary oocyte to complete meiosis II? Explanation: The secondary oocyte completes meiosis II only when fertilized by a spermatozoan. After fertilization is initiated, the secondary oocyte begins its second meiotic division, resulting in the formation of a mature ovum and another polar body.
What event causes a secondary oocyte to complete meiosis II?
After ovulation the oocyte is arrested in metaphase of meiosis II until fertilization. At fertilization, the secondary oocyte completes meiosis II to form a mature oocyte (23,1N) and a second polar body.
What happens to the secondary oocyte before fertilization?
Before fertilization, what happens to the secondary oocyte? … During meiosis 2, the secondary oocyte divides unevenly, with 1 cell (the ovum) receiving half of the chromosomes and nearly all the cytoplasm and organelles, while the other cell, the polar body, is much smaller and eventually degenerates.
What triggers the oocyte to complete meiosis?
Hormonal stimulation of diplotene-arrested oocytes initially triggers the resumption of meiosis by activating MPF, as at the G2 to M transition of somatic cells. As in mitosis, MPF then induces chromosome condensation, nuclear envelope breakdown, and formation of the spindle.
At what point does the secondary oocyte complete meiosis quizlet?
It will only complete meiosis at the time of ovulation (that is at the time the child reaches the puberty stage). By that time, the primary oocyte undergoes first meiotic division giving rise to one secondary ooctye and one polar body. You just studied 8 terms!
Under what circumstances does a secondary oocyte complete meiosis II quizlet?
Completion of Meiosis at fertilization
-If fertilization occurs, the secondary oocyte will complete meiosis II to form one large ovum (fully mature) and a second polar body that gets degenerated.
Which is true of a secondary oocyte?
Which is true of a secondary oocyte? It is nonfunctional and will degenerate. It has a potential to be fertilized by sperm.
What is the difference between a primary and secondary oocyte?
What Is the Difference Between a Primary Oocyte and a Secondary Oocyte? The primary oocyte is diploid and formed from oogonia after mitosis, whereas the secondary oocyte is formed from the primary oocyte after meiosis I and is haploid.
Why the secondary oocyte divides in this way?
The secondary oocyte divides unevenly in order to conserve the cytoplasm in the one functional ovum.
How is a secondary oocyte formed?
The secondary oocyte is the cell that is formed by meiosis I in oogenesis. … The secondary oocyte continues the second stage of meiosis (meiosis II), and the daughter cells are one ootid and one polar body. Secondary oocytes are the immature ovum shortly after ovulation, to fertilization, where it turns into an ootid.