Reproduction and Development Reproductive Systems Human Development

The Reproductive Systems Male Female Sexually Transmitted Infections Hormonal Regulation

The functions of the male reproductive system include: The functions of the male reproductive system include:male reproductive systemmale reproductive system 1.To produce male gametes (spermatogenesis) gametesspermatogenesisgametesspermatogenesis 2.To produce hormones (testosterone) testosterone 3.To maintain primary and secondary male sexual characteristics primary and secondary male sexual characteristicsprimary and secondary male sexual characteristics The Male Reproductive System

The functions of the female reproductive system include: The functions of the female reproductive system include:female reproductive systemfemale reproductive system 1.To produce female gametes (oogenesis) gametesoogenesisgametesoogenesis 2.To produce hormones (estrogen and progesterone) 3.To maintain primary and secondary female sexual characteristics primary and secondary female sexual characteristicsprimary and secondary female sexual characteristics 4.To maintain and deliver a developing fetus The Female Reproductive System

An STI is an infection that is transmitted only or mainly by sexual contact An STI is an infection that is transmitted only or mainly by sexual contact STI’s are caused by STI’s are caused by 1.Bacteria (gonorrhea, syphilis, chlamydia) gonorrheasyphilis chlamydiagonorrheasyphilis chlamydia 2.Viruses (HIV/AIDS, hepatitis B, genital herpes, HPV) HIV/AIDSHPVHIV/AIDSHPV 3.Parasites (pubic lice) pubic licepubic lice Sexually Transmitted Infections

The male reproductive system is influenced by a negative feedback loop and involves the following hormones: The male reproductive system is influenced by a negative feedback loop and involves the following hormones:negative feedback loopnegative feedback loop 1.GnRH: stimulates the release of FSH and LH from the anterior pituitary gland 2.FSH: stimulates spermatogenesis by the seminiferous tubules of the testes spermatogenesis seminiferous tubulesspermatogenesis seminiferous tubules 3.LH: stimulates testosterone production by the interstitial cells of the testes Hormonal Regulation

4.Inhibin: inhibits FSH production by the anterior pituitary gland 5.Testosterone: stimulates the development of the male reproductive system and secondary sex characteristics Hormonal Regulation

The female reproductive system is influenced by a negative feedback loop and involves the following hormones: The female reproductive system is influenced by a negative feedback loop and involves the following hormones:negative feedback loopnegative feedback loop 1.GnRH: stimulates the release of FSH and LH from the anterior pituitary gland 2.FSH: stimulates estrogen production and oogenesis by the follicles of the ovaries oogenesis 3.LH: stimulates ovulation and progesterone production by the corpus luteum of the ovaries Hormonal Regulation

4.Estrogen: stimulates the development of the female reproductive system and secondary sex characteristics 5.Progesterone: Causes uterine thickening and prevents uterine contractions * Hormones of the female reproductive system are secreted according to a 28 day cycle from puberty to menopause 28 day cycle28 day cycle Hormonal Regulation

Human Development Fertilization and Embryonic Development Fetal Development and Birth Reproductive Technology

The embryonic period of human development takes place from fertilization until 8 weeks The embryonic period of human development takes place from fertilization until 8 weeksfertilization The fetal period of development is from 8 weeks until full term (40 weeks) The fetal period of development is from 8 weeks until full term (40 weeks)fetal Fertilization is the joining of male and female gametes to form a zygote Fertilization is the joining of male and female gametes to form a zygote Fertilization zygote Fertilization zygote The gender of the zygote is determined by the X and Y chromosomes of the egg and sperm The gender of the zygote is determined by the X and Y chromosomes of the egg and spermX and Y chromosomesX and Y chromosomes Fertilization and Embryonic Development

The first cell divisions of the zygote is called cleavage The first cell divisions of the zygote is called cleavage cleavage Cleavage results in the formation of the blastocyst Cleavage results in the formation of the blastocyst blastocyst The blastocyst implants in the endometrium within 5 days of fertilization The blastocyst implants in the endometrium within 5 days of fertilizationimplants The implanted blastocyst begins secreting the hormone human chorionic gonadotropin (hCG) The implanted blastocyst begins secreting the hormone human chorionic gonadotropin (hCG)hormonehCGhormonehCG Fertilization and Embryonic Development

The blastocyst undergoes gastrulation to make three tissues (differentiation*) The blastocyst undergoes gastrulation to make three tissues (differentiation*)gastrulation 1.Endoderm Endoderm 2.Ectoderm Ectoderm 3.Mesoderm Mesoderm The extra-embryonic membranes develop The extra-embryonic membranes developextra-embryonic membranesextra-embryonic membranes The process of neurulation and organogenesis occur The process of neurulation and organogenesis occurneurulation organogenesisneurulation organogenesis Fertilization and Embryonic Development

Fetal development and human pregnancy is divided into three trimesters Fetal development and human pregnancy is divided into three trimesters 1.First Trimester (1-12 weeks) – Embryonic development completes – The embryo becomes a fetus embryo – The placenta grows from the chorion placenta – External reproductive organs are distinguishable – Teratogens are most harmful Teratogens Fetal Development and Birth

2.Second Trimester (13-24 weeks) – Fetal organs continue to grow and develop – Fetal skeleton begins to form bones – Mother begins to feel movement – Fetus is covered in fine hair and mucus Fetus – If the fetus is born prematurely he/she is unlikely to survive Fetal Development and Birth

3.Third Trimester (25-38 weeks) – Fetal organs continue to grow and develop – Testes descend in the male fetus – Fat layer forms and hair is lost – Digestive and respiratory systems complete development Fetal Development and Birth

The birthing process is called parturition and occurs due to hormonal changes The birthing process is called parturition and occurs due to hormonal changes hormonal changes hormonal changes The events of parturition are commonly called labour The events of parturition are commonly called labour Labour occurs in three stages Labour occurs in three stagesthree stagesthree stages 1.Dilation (2 -20 hours): Uterine contractions cause the cervix to dilate and the amnion ruptures Fetal Development and Birth

2.Expulsion (30 min-2 hours): forceful contractions push the baby through the cervix and the birth canal (a C- section may be necessary) a C- sectiona C- section 3.Placental: the placenta and umbilical cord are expelled about 30 minutes after the birth of the baby expelled Fetal Development and Birth

Lactation is the production of breast milk by the mother Lactation is the production of breast milk by the mother The hormone prolactin is secreted from the anterior pituitary gland and stimulates lactation The hormone prolactin is secreted from the anterior pituitary gland and stimulates lactation Expressing milk is due to the hormone oxytocin Expressing milk is due to the hormone oxytocinoxytocin Fetal Development and Birth

Categories of reproductive technologies include: Categories of reproductive technologies include: 1.Conception Control Preventing fertilization using physical barriers, spermicidal chemicals, surgery, NFP or hormones Preventing fertilization using physical barriers, spermicidal chemicals, surgery, NFP or hormones barriersNFPhormones barriersNFPhormones 2.Birth Control Preventing birth by inhibiting implantation or clinical abortion Preventing birth by inhibiting implantation or clinical abortioninhibiting implantationclinical abortioninhibiting implantationclinical abortion Reproductive Technology

3.Diagnostic Detecting fetal abnormalities before birth using ultrasound, amniocentesis, chorionic villus sampling and fetal surgery Detecting fetal abnormalities before birth using ultrasound, amniocentesis, chorionic villus sampling and fetal surgeryultrasoundamniocentesischorionic villus samplingfetal surgeryultrasoundamniocentesischorionic villus samplingfetal surgery 4.Fertility Increasing the likelihood of ovulation, fertilization or implantation using techniques including artificial insemination, invitro fertilization, and fertility drugs Increasing the likelihood of ovulation, fertilization or implantation using techniques including artificial insemination, invitro fertilization, and fertility drugsartificial inseminationinvitro fertilizationartificial inseminationinvitro fertilization Reproductive Technology