BIO 446L 1st Edition Lecture 35 Outline of Last Lecture I. Female Reproductive System contda. Uterine tubei. Fertilizationb. Uterusi. Layersc. Cervix and vaginad. Regulation of menstrual cyclei. Hormonal regulationii. Menstrual cyclinge. Mammary glandsi. Milk productionOutline of Current Lecture I. Female Reproductive System contda. Mammary glands contdi. Prolactinii. Breast cancerb. Embryonic implantation and placentac. 3 germ layersThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.i. Ectodermii. Mesodermiii. Endodermd. Pre-eclampsiaII. Male Reproductive Systema. Anatomyb. Testesi. Seminiferous tubulesii. Spermatic cordc. Seminiferous tubule—sertoli and interstitial cellsi. Sertoli cellsii. Myeoid cellsiii. Interstitial cells1. Leydig cellsd. Sertoli cellsi. Spermatogoniae. Interstitial Leydig cellsf. Spermatogenesisi. Blood testis barrierCurrent Lecture- Female Reproductive System Contd.o Mammary Glands contd Prolactin- Milk production during pregnancy and lactation Breast cancer- See MA in book for more details- Ductile cells are the common start site and primarily metastasizes to the bone firsto Embryonic implantation and placenta Implantation- At 5 days, blastocyte is now a hollow organ and looks for place to implanto Usually upper 1/3 of the posterior uterine wall Don’t want in cervix Sometimes anterior uterine wall- Embryonic blast/disc differentiates into the body and the trophoblast differentiates into the placenta fluid- Syncythiotrophoblasto Very active in implantationo Multi-nucleatedo Secretes digestive enzymes Digests endoderm tissue to make way for implanting and gets nutrients from mother’s blood- Embryonic blast with 2 layers at 10 days-2 weekso Bilaminan germinal disc with epiblast and hypoblasto Deeper penetration into endometriumo Differentiates into the body of the baby- At 10 days, endometrium seals over where embryo implants and becomes the decidua Placenta- Maternal artery and vein exchanges gas and nutrients with umbilical arteries and veins for placenta to deliver to embryo- Why is there not an immune response to reject fetus because the fetus is partly dad, geneticallyo Secretion of nitric oxide by immune cells involved in successful implantationo Three germ layers Ectoderm Mesoderm Endoderm- Contains yolk sac where gonads will form Three layers formed at three weeks From these three layers everything is formed Primitive streak= cells migrate from ectoderm to between the endoderm and form the mesoderm Outer cells of blastocyte—give rise to placenta Inner cells of blastocyte—give rise to the babyo Preeclampsia poor placenta implantation- it is unknown why high blood pressure, protein urea, and edema the disease arises in just days after implantation (4-5 days) but usually symptoms arise 24 weeks after gestation normally, cytotrophoblasts replace endothelium of smooth muscle lining the spinal artery- prevents contractility to allow blood to pump to placenta in preeclampsia, cytotrophoblasts don’t replact the wall- problem with cytokines released to signal this- spinal artery constricts with stress preventing proper blood flowo oxidative stress- babies born small and early, or don’t survive- only cured when placenta is removed- will occur for the mother with every pregnancy- Male Reproductive Systemo Keep in mind the similarities (more so than the differences) between male and femaleo Anatomy Gonads are outside the body When gametes produced, enter a series of tubes (like in females)- Sperm cells produced in testiso Sperm enters epididimusductus deferens (extends out ofscrotum) abdominal cavity ampula ejaculatory duct(fluid from seminal vesicle and prostate) prostatic urethra urethra (sperm leaves through penis)o Testes—Seminiferous Tubules Seminiferous tubules—produce sperm Tunica albugenia= Capsule around seminiferous tubules  Tunica vaginalis= covers the testes Spermatic cord= blood vessels, nerves, smooth and skeletal muscle- Smooth muscle= dartos- Skeletal muscle= cremaster- These muscles contract and relax the testes and the scrotum to cause them to rise towards the body when cold or drop away fromthe body when warmo Temperature control to maintain stable environment for sperm production Wall of seminiferous tubule is lined with Sertoli cells and spermatogenic cells- Sertoli cells= Pie-shaped cells (more on them later)- Spermatogenic cells will develop into sperm cellso Arranged in concentric lamellae in Sertoli cells (but technically not part of Sertoli cell)o Seminiferous tubule—Sertoli and interstitial cells Sertoli cells—receptors for FSH- Support spermatogenic cells Myeoid cells—movement of sperm Interstitial cells—produce testosterone with influence of LHo Sertoli Cells Line wall of seminiferous tubule Spermatogenic cells form concentric layers in/around Sertoli cell Spermatogonia= germ cells- Undeveloped until puberty, reside on basal surface of seminiferous tubule and surrounding Sertoli cells Binding site for FSH- Estradiol secretion- LH signals release of testosteroneo Binding site for androgen binding protein to concentrate testosterone “nurse” cells—make sure spermatocytes have nutrients- Form blood-testis barrier for bloodspermatocyte In fetus, secrete inhibin- Inhibits female development to promote male developmento Interstitial cells (Leydig cells) Oblond-shaped, secrete testosterone In fetus, GnRH stimulates dihydrotestosterone from Leydig cells At birth, Leydig cells become quiescent until pubertyo Spermatogenesis Begins at puberty Spermatogonia at basement membrane in periphery of seminiferous tubule outside tight junction- Keeps confined environment Blood-testis barrier- Sperm development does not occur until puberty (different from females whose eggs develop as they develop)- Sperm cells are brand new to body, so production can cause destruction due to the lymphocytes being producedo Barrier prevents an immune