The female reproductive system has several key functions: producing hormones, forming eggs, and developing offspring. The main organs are the ovaries, which produce eggs and hormones; the uterine tubes, which transport eggs; and the uterus, which nourishes development. The vagina serves as the birth canal. Eggs develop through oogenesis and are released during ovulation approximately every 28 days as part of the ovarian cycle.

1. FEMALE REPRODUCTIVE SYSTEM PRIMARY FUNCTIONS OF THE FEMALE REPRODUCTIVE SYSTEM ARE:- [1] PRODUCTION OF FEMALE HORMONES [2] FORMATION OF THE OVUM [3] DEVELOPMENT OF THE OFFSPRINGS

2. 2 FEMALE REPRODUCTIVE SYSTEM THE ORGANS AND THEIR FUNCTIONS:- OVARIES:- PRODUCE HORMONES & OVA UTERINE TUBES:- TRANSPORT THE OVA UTERUS:- OFFSPRING DEVELOPMENT CERVIX:- PROTECTION OF UTERUS VAGINA:- BIRTH CANAL & THE FEMALE ORGAN OF COPULATION EXTERNAL GENITALIA:- CLITORIS, LABIA MAJORA AND LABIA MINORA

3. 3 FEMALE REPRODUCTIVE ORGANS

4. Ovaries The ovary has an outer cortex – houses forming the gametes Inner medulla containing blood vessels and nerves

6. Structure of an ovarian follicle

7. Oocyte

9. Graafian (vesicular) follicle – growing follicle with a maturing oocyte

10. Ovulation – when the egg is mature the follicle ruptures

11. Occurs about every 28 days

13. Suspensory ligaments – secure ovary to lateral walls of the pelvis

14. Mesovarium ligaments – suspends it in between

17. Provide a site for fertilization

18. Attaches to the uterus

19. Does not physically attach to the ovary

22. Cilia inside the uterine tube slowly move the oocyte towards the uterus

24. Hollow, thick walled, muscular organ

25. Functions of the uterus

26. Receives a fertilized egg

27. Retains the fertilized egg

29. Fundus – area where uterine tube enters

31. Inner layer

32. Allows for implantation of a fertilized egg

33. Sloughs off if no pregnancy occurs (menses)

37. Behind bladder and in front of rectum

38. Serves as the birth canal

39. It is the female organ of copulation

41. 18 OOGENESIS

42. OVERIAN CYCLE FOLLICULAR PHASE:- THE DEVELOPMENT OF ONE PRIMARY FOLLICLE TO FORM A MATURE FOLLICLE OVULATION:- RUPTURE OF THE MATURE FOLLICLE TO RELEASE THE OVUM LUTEAL PHASE:- FORMATION OF THE CORPUS LUTEUM FROM THE RUPTURED MATURE FOLLICLE. DEATH OF THE CORPUS LUTEUM WILL FORM A CORPUS ALBICANS

43. The Ovarian Cycle The follicular phase: is the period of follicle growth, as lasting from the first to the fourteenth day of the cycle The luteal phase: is the period of corpus luteum activity, days 14-28 Typical ovarian cycle repeats at intervals of 28 days, with ovulation occurring midcycle

44. The follicular phase PRIMORDIAL FOLLICLE > PRIMARY FOLLICLE > SECONDARY FOLLICLE > MATURE FOLLICLE > OVULATION & RELEASE OF OVUM > CORPUS LUTEUM > CORPUS ALBICANS

45. THE OVARIAN CYCLE Primordial follicle Primary follicle primary oocyte arrested in prophase I + 1 layer of squamouslike cells primary oocyte that has resumed meiosis I + 1 layer of cuboidal follicle cells enclosing the oocyte Late secondary follicle Secondary follicle Two or more layers of granulosa cells surround the oocyte Layer of connective tissue condenses around the follicle forming theca folliculi Thick extracellular layer called zona pellucida

46. Mature (Vesicular) follicle Ovulation Fluid filled pockets coalesce to form central fluid filled cavity called an antrum The antrum isolate the oocyte with its surrounding capsule cells called a corona radiata Each month one of the ripening follicles ejects its oocyte from the ovary Secondary oocyte surrounded by its corona radiata

47. Corpus luteum remnants of follicle cells after ovulation Remaining granulosa cells increase in size and along with internal thecal cells 80% granulosa cells, 20% thecal cells Secrete progesterone and some estrogen Corpus albicans = scarred over corpus luteum

48. 25 The ovarian cycle

49. 26 OOGENESIS

50. Oogenesis Events of Oogenesis: Left flow chart of meiotic events, Right correlation with follicle development and ovulation in the ovary

51. OOGENESIS Mitosis in fetal life 2 meiotic arrests Total number of ova 6 months in utero birth number of germ cells (millions) puberty menopause 7 million at 5th month 2 million at birth 250,000 at puberty ~480 ovulations = ~13 per year for 37 years age oögonium (2n) primary oöcyte (2n) enters meiosis arrested in prophase I first meiotic division polar body 1 (1n) Stages of oögenesis secondary oöcyte (1n) Hormones arrested in metaphase II Gn-RF FSH LH estrogen fertilization completes meiosis II polar body 2 (1n) oötid (1n) + sperm (1n) = zygote

52. Differences between Spermatogenesis and Oogenesis Differences between Spermatogenesis and Oogenesis In females, mitotic proliferation of germ cells occurs prior to birth. In males, spermatogonia proliferate only after puberty. In female, meiotic divisions of oocyte produces only one mature ovum. In male, meiotic divisions of primary spermatocyte produces 4 mature spermatozoa In female, second meiotic division is completed only upon fertilization. In male, the products of meiosis (spermatids) undergo substantial differentiation in the maturing process.