Unit 12: Lesson 1 Reproductive System

Unit 12: Lesson 1 Reproductive System Review Textbook pages: 1056-1065, 1071-1080, 1088-1089 NURS 106 ‹#› Introduction The reproductive system includes: ● ● ● ● Gonads (Testes / Ovaries) Reproductive tract Accessory glands Perineal structures (External genitalia) The reproductive system is designed to perpetuate the species ● ● ● The male produces gametes called sperm cells The female produces gametes called ova Fertilization is the joining of a sperm cell and an ovum is; resulting in the formation of a zygote Anatomy of the Male Reproductive System ● ● ● ● Primary organ: Testes Accessory ducts: Epididymis; Ductus Deferens (vas deferens) Accessory glands: seminal glands’ prostate gland; bulbo-urethral glands External genitalia: scrotum; penis Loading… Prostatic urethra Pubic symphysis Urinary bladder Major Components of the Male Reproductive System Ducts Ureter Rectum Ejaculatory duct Accessory Glands Membranous urethra Seminal gland Spongy urethra Prostate gland Bulbo-urethral gland Ductus deferens Epididymis Gonad Testis Corpus cavernosum External Genitalia Penis Corpus spongiosum Scrotum External urethral orifice Anus Anatomy of the Male Reproductive Scrotum: System protects testes and functions to maintain appropriate temperature ● ● temperature for sperm development is 2°F cooler than body temperature; cremaster muscles will contract to pull scrotum closer to body if needed to maintain proper temperature Testes: ● ● ● paired, oval glands that produce testosterone site of sperm production (in seminiferous tubules) ducts of testes: ductus epididymis; ductus deferens; ejaculatory duct Spermatic cord Ductus deferens The Epididymis Head Efferent ductules Straight tubule Rete testis in mediastinum Epididymis: ● Seminiferous tubule site of sperm maturation; also functions in recycling Tunica albuginea covering testis of damaged sperm and adjusting composition of Scrotal cavity fluid made by seminiferous tubules a Diagrammatic view of the testis and epididymis Body Tail ● ○ ○ ○ ○ ● ○ ○ ○ ○ ● ○ ● ○ ● ○ ○ ● ○ Anatomy of the Male Reproductive System Ductus Deferens (vas deferens) carries sperm from epididymis and empties into prostatic urethra (with seminal vesicle) ampulla of the ductus deferens unites with the proximal region of the seminal vesicle - ejaculatory duct. conveys sperm through peristaltic contractions stored sperm remain viable for several months Seminal Vesicles Pair of pouch like organs found posterior to the base of bladder Produce viscous fluid that neutralizes vaginal secretions and contains fructose for ATP production, prostaglandins for sperm motility & viability, and clotting proteins for coagulation of semen Semen is a slightly alkaline mixture of sperm and seminal fluid Typical ejaculate is 2.5-5mL; Typical sperm count is 50-150 million/mL Ejaculatory Duct junction at the base of the seminal gland (where seminal vesicle and ampulla of ductus deferens meet); empties into urethra, adding fluid to prostatic urethra prior to ejaculation Urethra extends from urinary bladder to tip of penis; divided into the prostatic, membranous, and spongy regions. Prostate Gland inferior to bladder, surrounding the prostatic region of the urethra secretes slightly acidic prostatic fluid that increases sperm motility and viability Bulbourethral Glands small paired glands that secrete alkaline mucus into spongy region of urethra (for lubrication and neutralizing of acids) Loading… Sperm ● Spermatogenesis- the process of sperm production ● Important hormones for spermatogenesis include: FSH (follicle-stimulating hormone), LH (luteinizing hormone), GnRH (gonadotropin-releasing hormone), and testosterone. ● Sperm are produced in the seminiferous tubules of the testes, mature in the epididymis, and travel along the epididymis, ductus deferens, ejaculatory duct, and urethra before leaving the body. ● Divided into head, body, and tail (flagellum) portions. Mitochondria in body (midpiece) of sperm produces ATP that generates beating of flagellum Hormonal Regulation of Male Reproduction ー HCCXX * ^ Anatomy of the Female Reproductive System Primary Structures: Ovaries & Uterus Accessory Structures: Ovarian (fallopian) tubes; Vagina Accessory Glands: Urethral gland; Greater Vestibular Gland External Genitalia: Labia; Clitoris ‹#› Anatomy of the Female Reproductive System Ovaries: ● paired organs near lateral walls of pelvic cavity ● 3 main functions: production of immature female gametes (oocytes); secretion of female sex hormones (including estrogens & progesterone); secretion of inhibin (feedback control of FSH production) Uterine (fallopian) Tubes: ● extend from ovary to uterus ● 3 layers of tissue: ○ Mucosa- ciliated columnar epithelium with secretory cells provide nutrients & cilia move along ovum; Muscularis- circular & longitudinal smooth muscle; peristaltic contractions move ovum to the uterus; Outer serous membrane What is oogenesis? ‹#› Anatomy of the Female Reproductive System Uterus: ● Site of menstruation & development of fetus ● 3” long x 2” wide x 1” thick; inverted pear shape ● Anatomical subdivisions: fundus; body (uterine cavity); isthmus; cervix (internal and external os of cervical canal) ● Cervix- access to uterine cavity ● Histology: endometrium, myometrium (3 layers of smooth muscle); perimetrium Vagina: ● ● passageway for menstrual flow, spermatozoa, and lower portion of birth canal lies between urinary bladder and rectum ‹#› Uterine Tube Fimbriae Infundibulum Ampulla Isthmus Uterine part Uterine tube Fundus of uterus Ovarian artery and vein Mesovarium Body of uterus Perimetrium Myometrium Endometrium See Figure 27.16 Uterine artery and vein Ovary Ovarian ligament Uterine cavity Broad ligament Loading… Internal os (internal orifice) Isthmus of uterus Cervix Cervical canal Vaginal artery External os (external orifice) Vaginal rugae See Figure 27.19 Vagina Suspensory ligament of ovary Round ligament of uterus The Menstrual Cycle ● What is happening in the ovaries? ● What is a corpus luteum? ● What is happening in the uterus? ● Hormones to review: ○ FSH ○ Estrogen ○ LH ○ Progesterone ○ Uterine prostaglandin ○ GnRH ● ○ If fertilization and implantation do not occur Corpus luteum degenerates ‹#› Hormonal Regulation in Female Reproductive System ー ‹#› FOLLICULAR PHASE OF OVARIAN CYCLE 5 0 4 Gonadotropic 0 hormone 3 levels 0 (FSH and LH) 2 0 1 0 LUTEAL PHASE OF OVARIAN CYCLE LH GnRH pulse frequency (pulses/day) FSH Follicle stages during the ovarian cycle Tertiary ovarian follicle development Ovulation Corpus luteum formation Mature corpus luteum Corpus albicans Progesterone Ovarian hormone levels Estrogens Inhibin 28/ 0 © 2018 Pearson Education, Inc. 7 1 4 Days 2 1 28/ 0 ‹#› Unit 12: Lesson 2 Pregnancy & Human Development NURS 106 1 Terminology to Know ● Embryology- the study of the developmental events that occur during prenatal development ● Prenatal development - the developmental changes that occur in the period from conception to delivery ● Prenatal development can be further divided into: ○ Pre-embryonic development: begins at fertilization and continues through cleavage and mitosis implantation ○ Embryonic development: begins at implantation and continues to the end of the eighth developmental week. ○ Fetal development: begins at the start of the ninth developmental week and continues up to the time of birth. big growtn # 2 HIG = keepeverythinggoinanning Developmental Anatomy is intact 1. Pre-embryonic period ● 2 weeks period - Day o ○ fertilization; transportation of zygote ○ implantation; formation of embryonic tissue 2. Embryonic period ● 6 weeks period Loading… ○ differentiation of germ layers into body organs ○ formation of embryonic membranes; formation of placenta, umbilical cord 3. Fetal period ● ○ from 9 weeks until birth growth and specialization of body structures 3 meantaepment Prenatal Development / Gestation ↳38 The First Trimester (pre-embryonic period) ● ● ■ ● ■ ■ ■ Weeks 1-12 (Embryonic period- 3rd8th week) Four events within the first trimester Cleavage (sequence of cell divisions) A blastocyst forms Implantation (implantation into endometrial lining) Placentation (formation of the placenta) Embryogenesis (development of the embryo) layers beginning layers which Germ : becomes all tissues + _ layers Yolk zackiinital wite for blood cell development Amnonis Fluid: cushioning Chorion : Placenta contact to nutrients + starts , vili-grow enlarge maternal blood tissues = placenta make weeks = full term Placenta & Umbilical Cord ● Placenta is fully functional at 3rd month ● Chorionic villi extend into maternal blood filled intervillous spaces --maternal & fetal blood vessels do not join & blood does not mix ● Umbilical cord: Loading… ○ 2 arteries that carry blood to the placenta ○ 1 umbilical vein that carries oxygenated blood to the fetus 5 Hormonal Secretion by the Placenta pregnanae gutain tertone 6 Fetal Period: 9 – 12 weeks ● swallow and urinate into the amniotic fluid ● nervous system and muscle coordination developed ● Fetal Heart Sounds (FSH) ● Sex ↳ major systems ↳ Alcohol have been started at 12 weeks isdangerous more during this time 7 Fetal Period Continued 13 - 16 Weeks: ● Facial features well formed ● FHS ++ 26 - 29 Weeks: * ● begins to move into vertex position ー ↳ ready to be birth 30 - 38 Weeks: 17 - 20 Weeks: ● Quickening begins (feel fetal movements) ● vernix caseosa and lanugo (fuzzy) covering ↳ baby ↳ Fetal ● ● full term > 38 weeks lanugo hair is sparse nair 21 - 25 Weeks: ● surfactant begins to develop ● increasing fetal weight 8 Vertex positioning 9 ▪ Quick Review Second Trimester First Trimester At about week 4 of development ▪ ○ Embryo is physically and developmentally ▪ distinct from embryonic disc and extraembryonic membranes ○ Definitive orientation of embryo can be seen ▪ Events in first 12 weeks establish basis for ▪ organogenesis ○ Process of organ formation Fetus grows faster than surrounding placenta Amnion and chorion fuse, creating amniochorionic membrane Third Trimester: Most organ systems become able to function without maternal assistance ▪ Growth rate slows but much weight is gained ▪ Fetus and enlarged uterus displace many of mother’s abdominal organs 10 ▪ ▪ ○ ○ ○ ○ ○ ○ ○ Maternal Organ Systems & Support of Development Developing fetus is totally dependent on maternal organ systems for nourishment, respiration, and waste removal Maternal adaptations include: ↑effects of progesterone and relaxin ↑respiratory rate and tidal volume Loading… ↑ blood volume (almost 50%) ↑nutrient intake (10%–30%) ↑digestive system changes ↑glomerular filtration rate (50%) ↑size of uterus and mammary glands 11 Child Birth * Parturition ● Refers to labour, delivery, birth ● Requires: ○ Dilation of cervical canal to accommodate passage of fetus from uterus through vagina and to the outside ○ Contraction of uterine myometrium that are sufficiently strong to expel fetus poritivefeed back 12 Parturition Ψ ● Once contractions begin at labour onset, positive-feedback cycle progressively increases force ● Pressure of fetus against cervix reflexly increases oxytocin secretion ● Role of oxytocin: ↳have contractions when nursing (feeding) baby ○ Causes stronger contractions ○ Positive-feedback cycle progressively increases until cervical dilation and delivery are complete vertex positioning ! = baby to face tailbone , (face down) head firot > Down fuback Labour and Delivery X 3 stages of labor: 1. ○ ○ ○ 2. ○ ○ 3. ○ Stage of dilation 6-12 hours from onset of labor to the complete dilation of the cervix rupture of amniotic sac Stage of expulsion from complete cervical dilation to delivery of the baby 10 minutes to hours Placental stage 5 – 30 minutes 14 Placenta Umbilical cord Partially dilated cervix First stage of labor: Cervical dilation Uterus Second stage of labor: Delivery of the baby Third stage of labor: Delivery of the placenta 15 X Abnormalities of the Placenta Placenta previa ○ ○ ○ Abruptio placentae placenta implantation at the lower ○ segment of the uterus premature separation of the placenta obstructing the descent of the baby’s head bleeding may be concealed or revealed ○ presented with antepartum hemorrhage 16 Postnatal Stages X Neonatal period ▪ Birth to 1 month of age Infancy ▪ Continues through first year of life Childhood ▪ Infancy until adolescence Adolescence (puberty) ▪ Period of sexual and physical maturation AGING What is Senescence? ↳beginning at birth What are the impacts of senescence on the anatomy & physiology of the human body? 18