About Female Reproductive System
- Female reproductive system consists of the two ovaries, two oviducts (fallopian tubes), the uterus, cervix, a vagina, accessory genital glands, mammary glands, etc.
- In females, paired ovaries are located in the abdominal cavity near the kidney.
- The ovaries perform dual function of (i) production of female gamete (ovum) and (ii) secretion of female hormones (estrogen and progesterone). Each ovary is compared of ovarian follicles. At puberty, these follicles undergo maturation to produce ova.
- Near the posterior end of ovary, a funnel like structure leads into a long convoluted tube called fallopian tube. The fallopian tube from both sides open into a muscular structure, the uterus. Uterus opens into the vagina. Vagina is a tubular structure. it is also called birth canal. In female, urinary opening (urethra) and vaginal openings are separate.
- The ovaries start producing ovum (female gamete) at a definite age puberty (10-12 years).
- The ovarian follicles grow into mature follicle. Usually, one mature follicle develops to surround one ovum. the maturing ovum is from one of the two ovaries. The ovum is then released from the respective ovary by the process called ovulation.
- As the ovarinal follicle matures, the inner wall of uterus thickens to get prepared for receiving the developing zygote in case fertilization occurs.
- In case fertilization does not place, the thickened inner wall of the uterus breaks down along with its blood vessels and moves out of vagina in the form of bleeding, called menstrual flow (mensuration). It lasts for about 4-7 days.
- The cycle of events taking place in the ovaries and uterus every twenty eight days and marked by the menstrual flow is called menstrual cycle (sexual cycle in human female).
- In a normal healthy woman, ovulation takes place in the mid of the menstrual cycle around 14th day. Menstruation occurs every 28 to 30 days.
- The commencement of menstruation at puberty is termed menarche and marks the beginning of reproductive life of a women. The cycle of events in ovary and uterus stops around the age of 50 years in a human female. It is marked by the absence of menstrual cycle flow. The stoppage of menstrual cycle (sexual cycle in human female).
- In a normal healthy women, ovulation takes place in the mid of the menstrual cycle around 14 day. Menstruation occurs every 28 to 30 days.
- The commencement of menstruation at puberty is termed as menarche and marks the beginning of reproductive life of a woman. The cycle of events in ovary and uterus stops around the age of 50 years in a human female. It is marked by the absence of menstrual flow. The stoppage of menstrual flow and other events at this stage age is termed as menopause. the period between menarche and menopause, (12 to 50 years) is the normal reproductive life in human female.
- The function of the ovary and other reproductive organs are controlled by hormones released from hypothalamus and pituitary and the female hormones.
- A new born girl contain 2-4 ova in number, but of these only about 400 will mature during her life time.
- The beginning of this period of life is called puberty.
- The Luteinizing Hormone (LH) causes release of mature egg into fallopian tube follicle.
- The egg is fertilized in fallopian tube.
- Fertilization may occur between 11th to 15th days of the menstrual cycle.
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- Ovary is primary female sex organ.
- Ovary produces ova and secrets female sex harmones e.g. estrogen & progesterone.
- Discharge of a mature ovum from graffian follicle is known as ovulation. After ovulation, a ruptured follicle turns into a yellowish solid mass of cells called corpus luteum. Corpus luteum secrets the female hormone called progesterone.
- Progesterone (Sex Harmone) stimulates the uterus to develop blood capillaries to receive and nourish the fertilized ovum and also suppresses release of further production of ova.
- Progesterone controls the last two weeks of menstruation cycle. Secretion of progesterone is stopped if ovum is not fertilized.
- The destroyed capillaries of uterus is called menstruation blood.
- Estrogen is commonly secreted and controls first two weeks of menstruation cycle.
- Fallopian tubes are two in numbers and are also called oviducts or uterine tubes.
- Normally, Fertilization in mammals occurs in fallopian tube.
- Fertilizers in uterus is rare.
- If there is backage in fallopian tube, ova can not be fertilized..
- Both fallopian tubes opens into uterus.
- Uterus is situated above and behind the urinary bladder and remains attached to the bodywall by ligaments.
- The wall of uterus is composed of smooth muscle fibres called myometrium.
- Lumen of the uterus is lined by a mucous membrane called endometrium.
- Lower narrow end of uterus is called cervix.
- Uterus opens into an elastic muscular tube called vagina.
- The vagina is lined by a stratified squamous epithelium without any glands.
- During reproductive life the vagina contains Lactobacillus acidophilus which keeps the vaginal pH between 4.9 and 3.5 by producing lactic acid from glycogen.