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**[Spermatogenesis]** Spermatogonia (diploid) undergo mitosis to produce primary spermatocytes (diploid). Primary spermatocytes undergo meiosis I to form two secondary spermatocytes (haploid). The secondary spermatocytes undergo meiosis II to produce four spermatids (haploid). The spermatids differ...

**[Spermatogenesis]** Spermatogonia (diploid) undergo mitosis to produce primary spermatocytes (diploid). Primary spermatocytes undergo meiosis I to form two secondary spermatocytes (haploid). The secondary spermatocytes undergo meiosis II to produce four spermatids (haploid). The spermatids differentiate into mature sperm. 10/10✔️ **[Hormonal Regulation of Spermatogenesis]** **[Gonadotropin-Releasing Hormone (GnRH)]** Produced by the hypothalamus. Stimulates the pituitary gland to release FSH (Follicle-Stimulating Hormone) and LH (Luteinizing Hormone). 10/10✔️ **[Follicle-Stimulating Hormone (FSH)]** Released by the pituitary gland Promotes the maturation of spermatogonia into sperm cells. Stimulates Sertoli cells, which support and nourish developing sperm. \* 9/10✔️ **[Luteinizing Hormone (LH)]** Released by the pituitary gland. Stimulates Leydig cells to produce testosterone. 10/10✔️ **[Testosterone]** Produced by Leydig cells in response to LH. It acts on Sertoli cells to enhance the maturation of sperm cells. 10/10✔️ **[Negative Feedback of Spermatogenesis]** Testosterone levels rise as a result of LH stimulation, and this high level of testosterone inhibits the release of GnRH from the hypothalamus and LH from the pituitary gland. This helps maintain hormone balance. Sertoli cells also produce inhibin, which inhibits FSH release from the pituitary gland when sperm production is high. 9.5/10✔️ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Oogenesis]** The oogonia undergo mitosis to form primary oocytes. These primary oocytes are arrested in prophase of meiosis I. Each menstrual cycle, usually one primary oocyte, resumes meiosis I to produce a large secondary oocyte and a small polar body, which degenerates. The secondary oocyte begins meiosis II but is arrested in metaphase II. If fertilization occurs, the secondary oocyte completes meiosis II, producing a mature ovum and another polar body, which also degenerates. 10/10✔️ **[Hormonal Regulation of Oogenesis]** **[Gonadotropin-Releasing Hormone (GnRH)]** Produced by the hypothalamus. Stimulates the pituitary gland to release FSH (Follicle-Stimulating Hormone) and LH (Luteinizing Hormone). 10/10✔️ **[Follicle-Stimulating Hormone (FSH)]** Released by the pituitary gland. Stimulates the growth and maturation of ovarian follicles (which contain the oocytes). Promotes the secretion of oestrogen from developing follicles. 9/10✔️ **[Luteinizing Hormone (LH)]** Released by the pituitary gland. Triggers ovulation (the release of a mature egg from the follicle) and stimulates the conversion of the ruptured follicle into the corpus luteum. 9.5/10 ✔️ **[Oestrogen]** Produced by developing follicles in response to FSH. Promotes the thickening of the uterine lining (endometrium) in preparation for potential implantation of a fertilized egg. 10/10✔️ **[Progesterone]** Produced by the corpus luteum after ovulation in response to LH. Maintain the uterine lining for potential implantation and pregnancy if fertilization occurs. 9.5/10✔️ **[Negative Feedback of Oogenesis]** High levels of oestrogen inhibit the further release of FSH and LH, ensuring that only one follicle matures. After ovulation, progesterone and oestrogen from the corpus luteum inhibit GnRH, FSH, and LH, preventing the development of new follicles. 6/10 \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ 90.6 % Memory Retention \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Comparison of Egg and Sperm]** **[Sperm]** - - - - - - - **[Egg]** - - - - - - 10/10✔️ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  **[Implantation ( Draw )]** \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Extra embryonic Membranes]** **[Chorion]** ~~Facilitates gas exchange between the mother and fetus and develops into the fetal half of the placenta, which provides nutrients and oxygen.~~ **[Amnion]** Contains amniotic fluid **[Function of Amnion]** **1) Protection** The amnion contains amniotic fluid which helps to cushion the fetus against shocks and impacts. **2) Barrier** The amnion acts as a barrier to infections, helping to protect the fetus from pathogens that might enter the uterine environment. **3) Facilitating Movement** The amnion contains amniotic fluid which allows the fetus to move freely, which is important for musculoskeletal development. **4) Temperature Regulation** It helps maintain a constant temperature around the fetus, contributing to a stable developmental environment. **[Allantois]** ~~Collects nitrogenous wastes (urea) produced by the fetus and facilitates their transfer to the mother for excretion. Its blood vessels contribute to the formation of the umbilical cord, connecting the fetus to the placenta.~~ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Placenta]** **[Structure and Formation of Placenta( Development )]** The placenta begins to form upon embryo implantation and reaches full maturity by the tenth week of pregnancy. It consists of two distinct sides: **[Fetal Side]** Derived from the chorion, which develops from the trophoblast cells of the blastocyst. This side contains chorionic villi that interact with maternal blood. **[Maternal Side]** Derived from uterine tissues, this side provides the necessary environment for exchange. Gas and nutrient exchange occurs at the chorionic villi, where fetal blood, rich in carbon dioxide and metabolic waste, meets maternal blood, which supplies oxygen and essential nutrients. The umbilical cord connects the fetus to the placenta, containing two umbilical arteries (carrying deoxygenated blood) and one umbilical vein (carrying oxygenated blood). The maternal and fetal blood do not mix because the chorionic villi extend into the maternal blood supply, allowing for nutrient and waste exchange without direct connection to fetal blood vessels. 9/10✔️ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Functions of Placenta]** **[Acts as endocrine organ]** The placenta produces hormones such as hCG ( Human chorionic gonadotropin ), progesterone, and oestrogen to support the pregnancy. **[Acts as a barrier]** The placenta acts as a barrier to certain pathogens; however, some viruses, such as HIV, can cross the barrier, prompting maternal therapy to reduce transmission risks. It also protects the fetus from many harmful substances, though toxins from cigarettes, alcohol, and illicit drugs can permeate the placenta, endangering fetal development. For instance, fetal alcohol syndrome can result from maternal alcohol consumption, leading to growth defects and neurological issues. Smoking constricts blood vessels, reducing nutrient delivery and potentially causing fetal growth retardation. **[Exchange]** Facilitates the exchange of gases, nutrients, and waste between the mother and fetus \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Maternal Behaviour During Pregnancy]** **[Physiological Changes]** **[Hormonal Changes]** The production of hormones such as estrogen, progesterone, and human chorionic gonadotropin (hCG) increases. These hormones regulate various bodily functions and prepare the body for childbirth and breastfeeding. **[Physical Adjustments]** The body undergoes changes like weight gain, increased blood volume, and enlargement of the uterus to accommodate the growing fetus. **[Nutritional Needs]** **[Increased Appetite]** Pregnant women often experience an increase in appetite to supply the necessary nutrients for fetal development. **[Balanced Diet]** A diet rich in vitamins, minerals, proteins, and carbohydrates is essential. Folate, iron, calcium, and omega-3 fatty acids are particularly important for fetal growth and brain development. **[Behavioral Adaptations]** **[Nesting Instinct]** Many women experience a nesting instinct, a strong urge to prepare their home for the baby. This can involve cleaning, organizing, and creating a safe environment. **[Emotional Changes]** Hormonal fluctuations can lead to mood swings, increased sensitivity, and emotional responses. **\_\_\_\_** **Regular Health Visit** **Immunization of the mother** **No alcohol** **No smoking** \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Maternal Nutrition]** Maternal nutrition is vital for healthy fetal development, with several key nutrients playing critical roles: **[Folic Acid]** Essential for nervous system development; helps prevent spina bifida and other neural tube defects. **[Calcium]** Necessary for fetal bone development; deficiencies can lead to calcium being drawn from the mother\'s bones. **[Protein]** Crucial for the growth of fetal tissues; insufficient intake can result in low birth weight and cognitive impairments. **[Iron]** Vital for hemoglobin production; a lack of iron can cause maternal anemia as the fetus absorbs iron from the mother. Pregnant women should adhere to a balanced diet rich in whole grains, lean proteins, dairy products, fruits, and vegetables, along with increased caloric intake to support the developing fetus effectively. \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Acrosomal Reaction]** acrosome( located at the tip of the sperm\'s head) zona pellucida( outermost layer of the egg cell ) , a glycoprotein barrier that prevents unauthorized entry. The acrosomal reaction begins when the sperm reaches the zona pellucida and binds to specific receptors on its surface. This binding is highly specific, ensuring that only sperm from the same species can fertilize the egg. Once binding occurs, the acrosome releases digestive enzymes, such as hyaluronidase and acrosin. These enzymes start to break down the zona pellucida, creating a passage for the sperm to reach the egg. The sperm begins to penetrate zona pellucida , propelling itself forward with its flagellum. The progressive breakdown of the zona pellucida allows the sperm to get closer to the egg\'s plasma membrane. When the sperm reaches this membrane, the membranes of the sperm and egg fuse, facilitating the entry of the sperm's nucleus into the egg. Following the acrosomal reaction, the egg undergoes a secondary process known as the cortical reaction. This reaction involves changes to the egg\'s surface that prevent additional sperm from entering. \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **[Abstinence]** [Procedure] refrain from sexual intercourse [Methodology] no sperm in vagina [Effectiveness] 100% [Risk] none 10/10 **[Vasectomy]** [Procedure] vasa deferentia cut and tied [Methodology] no sperm in seminal fluid [Effectiveness] almost 100 % [Risk] irreversible sterility 10/10 **[Tubal ligation]** [Procedure] oviducts cut and tied [Methodology] no eggs in oviduct [Effectiveness] almost 100% [Risk] irreversible sterility 10/10 **[Oral contraception]** [Procedure] hormone medication taken daily [Methodology] anterior pituitary does not release FSH and LH [Effectiveness] almost 100% [Risk] blood clots, especially in smokers 8/10 **[Contraceptive implants]** [Procedure] tubes of progestin (form of progesterone) put under skin [Methodology] anterior pituitary does not release FSH and LH [Effectiveness] more than 90 % [Risk] none known at present 9.5/10 **[Diaphragm]** [Procedure] latex cup inserted into vagina to cover cervix before intercourse [Methodology] blocks entrance of sperm to uterus [Effectiveness] with jelly, more than 90 % [Risk] none known at present 8.5/10 **[Male condom]** [Procedure] latex sheath fitted over erect penis [Methodology] traps sperm and prevents STDS [Effectiveness] about 85% [Risk] none known at present **[Female condom]** [Procedure] polyurethane liner fitted inside vagina [Methodology] blocks entrance of sperm to uterus and prevents STDs [Effectiveness] about 85% [Risk] none known at present **[Coitus interuptus]** [Procedure] penis withdrawn before ejaculation [Methodology] prevents sperm from entering vagina [Effectiveness] 75% [Risk] none known at present **[Jellies, creams and foams]** [Procedure] spermicidal products placed in vagina before intercourse [Methodology] kill many sperm [Effectiveness] about 75% [Risk] none known at present **[Natural family planning]** [Procedure] day of ovulation determined by record keeping [Methodology] intercourse avioded on certain days of the month [Effectiveness] about 70% [Risk] none known at present