Tiêu đề 03. HUMAN REPRODUCTION.pdf ✅

HUMAN REPRODUCTION Process of formation of ovum. Female gamete is ovum. One oogonium produces only one ovum Mammary glands are characteristic of female mammals. Are paired Structures that has mammary lobes containing alveoli Alveoli cells secrete milk External genialia includes mons pubis, labia majora, labia minora hymen & clitoris Accessory ducts are fallopian tubes (oviducts), uterus, Vagina & Cervix fallopian tube divided into Infundibulum, Ampulla & Isthmus Ovaries located on either side of abdomen Ovaries produce ovum and ovarian hormones Spermatogonia are male germ cells that undergoes meiosis to form spermatozoa Sertoli cells provide nutrition to germ cells Leydig cells produce testosterone. Accessory glands are seminal vesicles, prostate gland & cow peris gland Process of formation of sperms Male gamete is sperm cell One spermatogium produces 4 sperms Hormones GnRH, LH, FSH & Androgens support spermatogenesis Hormones FSH, estrogen, LH, progesterone support oogenesis • • • • • • • • • • • • External genitalia Accessory glands Pair of testes Accessory ducts Pair of ovaries Accessory ducts Accessory glands External genitalia Accessory ducts store & transport sperms from testis to urethra. Accessory ducts are vasa efferentia, vasa deferentia, epididymis, ejaculatory, ducts, urethra & rete testis Process of production of milk by mammary glands is called lactation. Milk production starts at the end of pregnancy. Colostrum is the first milk after birth Parturition is child – birth Process of delivery of fetus at the end of pregnancy. Oxytocin is the hormone that initiates uterine contraction for birth Gestation period is average duration of pregnancy (conception to birth). It is 9 months for humans • Progression of pregnancy is marked by formation of placenta. • Placenta is structural & functional unit that establishes common connection between fetus & mother. • Placenta connected to embryo through umbilical cord. • Umbilical cord transports nutrients & water to & from the embryo Testis located in scrotum Has seminiferous tubules Seminiferous tubules lined by spermatogonia & Sertoli cells. Implautation of Embryo occurs in the uterine wall After fertilization, Zygote under goes cleavage to form 2, 4, 8, 16 celled stage 64- celled stage is called blastocyst (blastula). Implantation occurs at blastula stage. Implantation leads to pregnancy • • • • • Fusion of haploid male gamete with haploid female gamete. Fusion of sperm & ovum forms, single– celled Zygote Fertilization occurs in ampullary–isthmus junction of fallopian tube. Menstrual cycle is a cyclic event in human females & other primates for ovulation. The cycle starts (menarche) at puberty & stops (menopause) at age of 45 – 50 years. It has 4 phases Menstrual phase (bleeding phase, Follicular phase (proliferative phase), ovulatory phase & Luteal phase (secretory phase). The cycle repeats after every 28 days. Ovulation occurs on the 14th day of Menstrual cycle. • • • • • • • • • • Accessory glands secrete various alkaline secretions to nourish the sperms Placenta secretes hormone estrogens, progesterones, HCG & hpL, prolactin to support pregnancy & for growth of embryo OOGENESIS IMPLANTATION PREGNANCY AND PARTURITION MALE REPRODUCTIVE SYSTEM ACCESSORY DUCTS TESTIS GLANDS ACCESSORY FEMALE REPRODUCTIVE SYSTEM MAMMARY GLANDS GESTATION PERIOD FERTIL ZI ATION MENSTRUAL CYCLE GAMATOGENES O IS OGE N E SI E S MBRYONIC DEVELOPMENT LACTATION ACCESSORY DUCTS EXTERNAL GENITALIA OVA RIES SPERMATOGENESIS • • • • • • • • • • • • • • • • • • • • SPERMATOGENESIS FEMALE REPRODUCTIVE CYCLE