{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

A&PII Repro Lectures.final F10

A&PII Repro Lectures.final F10 - The Reproductive...

Info icon This preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: The Reproductive System The Genetics—you and your gametes Genetics—you Humans have 46 chromosomes “Diploid” or “2n” Humans 23 pairs of similar (homologous) chromosomes pairs But we get half our DNA/chromosomes/genes from But our mothers and half from our fathers… our 23 chromosomes “Haploid” or “n” Sperm and eggs are made from regular cells that Sperm contain the full amount (diploid) of genetic material, but have to end up with only half as much… but MITOSIS and MEIOSIS! The Human Life Cycle The In the reproductive system… In Primary sex organs (gonads—ovaries, testes) - gametes (eggs, sperm) gametes - sex hormones (estrogens, progesterone, testosterone) sex Accessory reproductive organs - ducts, glands, “external” genitalia ducts, Secondary sexual characteristics Secondary - hair growth, breast development, voice changes hair Male reproductive anatomy Male Anatomy of the testis Anatomy Spermatogenesis Spermatogenesis Mitosis of spermatogonia Meiosis: spermatocytes to Meiosis: spermatids spermatids Spermiogenesis: Spermiogenesis: spermatids to sperm spermatids (spermatozoa) Sperm development Sperm Sperm formation and transport Sperm Made in seminiferous tubules, then travel through: Tubulus rectus, Rete testis, Efferent ductules Epididymis (head body tail) Epididymis Ductus deferens (vas deferens) Ejaculatory duct Urethra Semen: Seminal vesicles seminal fluid, alkaline, sugar Seminal Prostate gland sperm activation, food, PSA Prostate Bulbourethral glands mucus, prior to ejaculation Brain-Testicular Axis Axis Hormonal control of androgen Hormonal and sperm production and 1. Hypothalamic GnRH (gonadotropin-releasing hormone) 2. Pituitary FSH and LH (follicle-stimulating hormone and (follicle-stimulating luteinizing hormone) luteinizing 3. Testicular androgens 4. Negative feedback Female reproductive anatomy Female Reproductive organs Reproductive Oogenesis Oogenesis Takes YEARS to complete! Mitosis of oogonia (2n) during Mitosis development development Oogonia become primary Oogonia oocytes oocytes Start first meiosis but then sit Start there until puberty! there Some are recruited each month Some to become secondary oocytes to Stops in Meiosis II unless Stops fertilized fertilized (in humans) Title Title Hormonal regulation of the ovarian cycle Hormonal control of reproduction Hormonal Hypothalamus Anterior Pituitary _ GnRH _ FSH/LH + + Target Tissue FSH: follicle growth and maturation (oogenesis) (oogenesis) LH: estrogen LH: In the male: Testes/Ovaries (negative feedback!) In the female: Testosterone Estrogen Estrogen Progesterone FSH: spermatogenesis FSH: LH: testosterone LH: The Ovarian Cycle Cycle Start here Hormones and the menstrual cycle (28d) menstrual Follicular phase (menstrual and proliferative phases) Luteal phase (secretory phase) Ovulation LH / FSH (positive feedback!) LH (positive Estrogen Progesterone The Reproductive System The - Pregnancy, Parturition and Lactation - Fertilization Fertilization Acrosomal reaction - hyaluronidase hyaluronidase - acrosomal enzymes acrosomal Fusion of plasma Fusion membranes membranes Cortical reaction - block other sperm Events immediately after Fertilization Events Sperm entry into secondary oocyte Meiosis II Second polar body discarded Pronuclei come together DNA replicates Chromosomes form Mitosis Fertilization / Pregnancy Fertilization Implantation and Development Development Know these terms: Know • Placentation—formation of placenta • Gastrulation—germ layer formation – Endoderm: becomes visceral tissues (gut, respiratory) – Mesoderm: becomes notochord, bone, muscle and connective tissues, Mesoderm: gonads and kidneys, cardiovascular system – Ectoderm: becomes nervous system and body coverings • Organogenesis—differentiation of germ layers • Neurulation—first major event in organogenesis; Neurulation—first production of brain and spinal cord from ectoderm production Hormones in Pregnancy Hormones Parturition Parturition Positive Positive feedback! feedback! Stages of Stages labor: labor: Dilation Expulsion placental Mammary glands Mammary Lactation Lactation Positive Positive feedback! feedback! Prolactin Oxytocin Mechanoreceptors Development and Aging Development Gender development Gender Sex chromosomes: X and Y Females are XX, Males are XY Father (sperm) determines the baby’s sex Female is the default pathway—must have: Female - testis-determining factor (TDF, from SRY gene on testis-determining Y chromosome) - anti-Mullerian hormone (AMH) anti-Mullerian Puberty Puberty When you become reproductively functional Increasing levels of testosterone in males, estrogen in Increasing females females Re-setting of the hypothalamic-pituitary-gonadal Re-setting axes at a higher set point axes Development of secondary sexual characteristics Menstruation Menopause (Andropause?) Menopause Decreased estrogen production in women with age Menstruation becomes erratic and shorter, eventually Menstruation ending completely ending Estrogen production stops: - Atrophy of reproductive organs, sexual function Atrophy - Increased total blood cholesterol, lower HDL Increased - Cardiovascular complications Cardiovascular - Bone loss Bone - Breast cancer? Breast What else happens as you age? What Decreased secretion of other hormones (growth hormone, thyroid, etc.) (growth Loss of muscle mass and function Cardiovascular deconditioning Vision and/or hearing loss Memory function deteriorates ...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern