8.4.3 Oogenesis: Meiosis in Females

Question 1

meiosis

Answer 1

• the division of a diploid nucleusto form four haploidcells. The first division of meiosis involves the separation of homologous chromosomes, while the second division involves the separation of chromatids. Haploid cells that are able to take part in sexual reproduction are called gametes

Question 2

oogenesis

Answer 2

• a process that involves meiosis to form a haploid egg cell and three haploid polar bodies. Oogenesis takes
  place in the ovary of the female reproductive system
• Cytokinesis during oogenesis is unequal, resulting in an egg that has a lot of cytoplasm and smaller cells called polar bodies. The polar bodies degenerate while the large amount of cytoplasm in the ovum furnishes nutrients to the developing zygote
• In the process of oogenesis the oogonium develops into a primary oocyte.
• The primary oocyte undergoes meiosis I to form one polar body and one haploid cell called the secondary oocyte.
• The secondary oocyte undergoes the second division of meiosis only when it has been fertilized. The second meiotic division will produce the ovum and another polar body. The polar bodies will degenerate, while the ovum will become the zygote upon fertilization.
• Here is a view of oogenesis from the perspective of the ovary.
• The primary oocyte is enclosed by a structure called the follicle. As the primary oocyte develops into the secondary oocyte, the follicle grows.
• The secondary oocyte will eventually rupture from the follicle and will remain a secondary oocyte unless it is fertilized. After the secondary oocyte ruptures from the follicle, the follicle tissue becomes the corpus luteum.

Question 3

True or false?

In female germ cells, prophase I begins in early fetal development and ends years later.

Answer 3

• true

Question 4

The purpose of the formation of polar bodies is

Answer 4

• to conserve cytoplasm in the developing oocyte for the egg cell

Question 5

Which statement regarding oogenesis is correct?

Answer 5

• The polar bodies will degenerate

Question 6

Meiosis in the female occurs in which organ?

Answer 6

• ovary

Question 7

During oogenesis, which cell must be fertilized to complete meiosis?

Answer 7

• secondary oocyte