Summary
Development of egg cells in the ovary, with unequal division creating one large ovum and polar bodies.
In depth
Primary oocytes start meiosis before birth and arrest in prophase I. At ovulation the secondary oocyte arrests in metaphase II and completes meiosis only if fertilised. Polar bodies discard extra chromosomes.
Oogenesis is discontinuous: starts in fetus, pauses, resumes at puberty. Only about 400 oocytes are ovulated. Polar bodies get little cytoplasm.
Key idea: one oocyte yields one egg and three polar bodies.
Frequently asked questions
What is Oogenesis?
Development of egg cells in the ovary, with unequal division creating one large ovum and polar bodies.
Which area of biology covers Oogenesis, and how advanced is it?
Oogenesis is one of the 54 topics in Reproduction & Endocrinology. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Spermatogenesis, Ovulation, Puberty.
Can you give an example of Oogenesis?
Only one mature egg results from each oogonium.
What should I learn before Oogenesis?
Work through the Beginner topics in Reproduction & Endocrinology first, such as Reproduction, Asexual Reproduction, Sexual Reproduction, then return to Oogenesis. Intermediate topics assume the Beginner vocabulary.
What topics are related to Oogenesis?
The closest topics to Oogenesis are Spermatogenesis, Ovulation, Puberty, Gametes. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Oogenesis?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Oogenesis. To practise the whole of Reproduction & Endocrinology, use the Reproduction & Endocrinology quiz.
How is Oogenesis different from Spermatogenesis?
Oogenesis: Development of egg cells in the ovary, with unequal division creating one large ovum and polar bodies. Spermatogenesis: Production of sperm in the seminiferous tubules by meiosis and differentiation. Read both side by side and note what each one explains.
How should I study Oogenesis step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Spermatogenesis and explain the difference aloud. Finally, take the Reproduction & Endocrinology quiz and come back to this page for any question you miss.