Biology Sylvia S. Mader Michael Windelspecht Chapter 41 Reproductive Systems Lecture Outline See separate FlexArt PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes. 1 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1

Biology, 9th ed, Sylvia Mader Chapter 43 Outline Reproductive Systems 41.1 How Animals Reproduce 41.2 Human Male Reproductive System 41.3 Human Female Reproductive System 41.4 Control of Human Reproduction 41.5 Sexually Transmitted Diseases

Biology, 9th ed, Sylvia Mader Chapter 43 41.1 How Animals Reproduce Reproductive Systems Asexual Reproduction Some invertebrates can reproduce asexually: Sponges, cnidarians, flatworms, annelids, echinoderms Ex: Hydras can reproduce asexually as an outgrowth (bud) of the parent Ex: Flatworms reproduce asexually by splitting in half Ex: Sponges, annelids, and echinoderms can have the ability to regenerate from fragments

Biology, 9th ed, Sylvia Mader Chapter 43 Reproduction in Hydra Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. budding of new polyp parental polyp © Dr. Dennis Kunkel/Visuals Unlimited

Biology, 9th ed, Sylvia Mader Chapter 43 How Animals Reproduce Reproductive Systems Sexual Reproduction Animals usually produce gametes in specialized organs termed gonads Testes produce sperm Ovaries produce eggs Parthenogenesis Modification of sexual reproduction Unfertilized egg develops into a complete individual

Damselflies Mating on Land Biology, 9th ed, Sylvia Mader Chapter 43 Damselflies Mating on Land Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. male grasps female female curls tail © Herbert Kehrer/zefa/Corbis

Human Male Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Male Reproductive System Reproductive Systems Production of Sperm Seminiferous tubules Tubes packed with cells undergoing spermatogenesis Spermatogonia divide to produce primary spermatocytes Primary spermatocytes undergo meiosis I to produce secondary spermatocytes Secondary spermatocytes undergo meiosis II to produce four spermatids, each of which matures into a sperm cell Consists of three parts: head – acrosome and nucleus middle piece tail

Biology, 9th ed, Sylvia Mader Chapter 43 Testis and Sperm Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. vas deferens epididymis interstitial cells immature sperm Sertoli cell uncoiled seminiferous tubule lobule testis scrotal sac 100 µm b. Seminiferous tubules a. Testis, cut to show lobules (b): © Anatomical Travelogue/Photo Researchers, Inc.

Biology, 9th ed, Sylvia Mader Chapter 43 Testis and Sperm Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. MITOSIS MEIOSISI MEIOSISII spermatogonium (diploid) primary spermatocyte (diploid) secondary spermatocyte (haploid) early spermatid (haploid) late spermatid (haploid) immature sperm (haploid) acrosome head middle piece tail nucleus of Sertoli cell end piece c. Spermatogenesis d. Sperm 9

Human Male Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Male Reproductive System Reproductive Systems Hormonal Regulation in Males Hypothalamus has ultimate control of testicular sexual function Gonadotropic-releasing hormone (GnRH) stimulates production of the gonadotropic hormones by the anterior pituitary Follicle Stimulating Hormone (FSH) Promotes spermatogenesis in the seminiferous tubules Luteinizing Hormone (LH) Controls production of testosterone by the interstitial cells of testes

Human Male Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Male Reproductive System Reproductive Systems Hormonal Regulation in Males Testosterone Major sex hormone in males Establishes and maintains secondary sex characteristics Responsible for greater muscular development in males

Hormonal Control of the Testes Biology, 9th ed, Sylvia Mader Chapter 43 Hormonal Control of the Testes Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. hypothalamus - GnRH - anterior pituitary - - FSH LH + + Seminiferous tubules produce sperm plus inhibin. Interstitial cells produce testosterone. testis

41.3 Human Female Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 41.3 Human Female Reproductive System Reproductive Systems The Ovaries, Uterus, and Vagina An oocyte (egg) bursts from an ovary into the coelom Swept into oviduct by the fimbriae of the oviducts and the beating of cilia lining the oviducts Fertilization normally occurs in the oviduct Ciliary action moves the developing embryo to the uterus Embryo embeds in the uterine lining (endometrium)

Human Female Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Female Reproductive System Reproductive Systems The Ovaries, Uterus, and Vagina (cont.) Cervix Narrow end of the uterus Opening in the cervix leads to the vaginal canal Vagina Tube at a 45-degree angle to the small of the back Contains mucosal lining Bacteria create an acidic environment Protects against the growth of pathogenic bacteria

Human Female Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Female Reproductive System Reproductive Systems The Female Orgasm External genital organs are collectively known as the vulva Mons pubis, labia minora, and labia majora are on either side of the urethral and vaginal openings Clitoris has a shaft of erectile tissue and is capped by a pea-shaped glans

Human Female Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Female Reproductive System Reproductive Systems The Ovarian Cycle Follicle changes from a primary to a secondary to a vesicular (Graafian) follicle under the influence of FSH and LH Ovulation Release of secondary oocyte from a vesicular follicle Secondary oocyte enters an oviduct Follicle develops in corpus luteum Degenerates if pregnancy does not occur

Biology, 9th ed, Sylvia Mader Chapter 43 Ovarian Cycle Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 2. The secondary follicle contains a secondary oocyte. 3. Vesicular (Graafian) follicle develops. secondary follicle vesicular (Graafian) follicle primary follicles secondary oocyte 1. A primary follicle contains a primary oocyte. Ovarian cycle 6. Corpus luteum degenerates. 4. Ovulation: Oocyte is released. corpus luteum 5. Corpus luteum develops. oocyte a. first polar body second polar body sperm Sperm enters, and meiosis II goes to completion. MEIOSIS I MEIOSIS II primary oocyte (46 chromosomes) secondary oocyte (23 chromosomes) egg b. © Ed Reschke/Peter Arnold, Inc.

Human Female Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Female Reproductive System Reproductive Systems Phases of the Ovarian Cycle Follicular Phase FSH promotes the development of a follicle Follicle then secretes estrogens Luteal Phase LH promotes development of the corpus luteum Corpus luteum then secretes progesterone

Hormonal Control of Ovaries Biology, 9th ed, Sylvia Mader Chapter 43 Hormonal Control of Ovaries Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. hypothalamus -/+ GnRH - anterior pituitary - -/+ FSH follicle + LH + corpus luteum oocyte estrogen progesterone

Female Hormone Levels During the Ovarian and Uterine Cycles Biology, 9th ed, Sylvia Mader Chapter 43 Female Hormone Levels During the Ovarian and Uterine Cycles Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Anterior pituitary Hormone Levels FSH LH Ovarian cycle Ovarian Events developing follicles mature follicle Ovulation corpus luteum Follicular Phase Luteal Phase estrogen Hormone Levels progesterone Uterine cycle Endometrium Menstruation Proliferative Phase Secretory Phase Days 1 3 5 7 9 11 13 15 17 19 21 23 25 27 30

Human Female Reproductive System Biology, 9th ed, Sylvia Mader Chapter 43 Human Female Reproductive System Reproductive Systems Fertilization and Pregnancy If fertilization occurs, an embryo begins developing as it travels down the oviduct to the uterus The embryo becomes embedded in the uterine lining several days after fertilization Placenta produces human chorionic gonadotropin (HCG) Maintains the corpus luteum until placenta begins production of progesterone and estrogen Detected in pregnancy tests 21