1 / 21

The Reproductive System

The Reproductive System. Chapter 16. Intro to reproductive system. All other systems act continuously, but reproductive doesn’t come online time puberty Gonads – testes and ovaries, primary sex organs Gonads – produce gametes and secrete sex hormones Males – sperm Females - ova

gary-norris
Download Presentation

The Reproductive System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Reproductive System Chapter 16

  2. Intro to reproductive system • All other systems act continuously, but reproductive doesn’t come online time puberty • Gonads – testes and ovaries, primary sex organs • Gonads – produce gametes and secrete sex hormones • Males – sperm • Females - ova • Accessory reproductive organs • Joint purpose of male and female reproductive system is to produce offspring

  3. Anatomy of Male • 1° organ are testes (gonads) • Exocrine function - sperm producing • Endocrine function - testosterone • Accessory structures are ducts or glands that deliver sperm to body exterior or female reproductive tract.

  4. Testes • Scrotum - skin • Tunica albuginea – fibrous connective tissues surrounds each tetis • Extends into testis and divides into lobules • 1-4 seminiferous tubules in each lobules • Sperm forming factories • Rete testis -> epididymis (first part of duct system) • In soft conn. Tissue surrounding seminiferous tubules are interstitial cells secrete testosterone Figure 16.1

  5. Duct SystemEpididymus • Highly coiled tube – about 20ft • Part of duct system • Storage site for immature sperm entering from testis • Sperm travel takes about 20 days, maturing, gain ability to swim • Ejaculation – walls contract to expel sperm into next part of duct system Figure 16.2b

  6. Duct SystemDuctus Deferens – vas deferens • Runs from testis over bladder • Enclosed by connective tissue sheath called spermatic cord with blood vessels and nerves • Empties into ejaculatory duct – passes through prostate to merge with urethra. • Ejaculation – smooth muscle in wall create peristaltic waves move sperm • Vasectomy – ties off vas deferens in scrotum • Sterile? • Testosterone? Figure 16.2a

  7. Duct SystemUrethra • Last part of duct system • 3 regions • Prostatic urethra – surrounded by prostate • Membranous urethra • Spongy (penile) urethra –length of penis • Carries both urine and sperm, but never at same time • Ejaculation – sperm enter prostatic urethra from ejaculation ducts, bladder sphincter constricts, no sperm in bladder, no urine in ejaculate

  8. Accessory GlandsSeminal Vesicles • Base of bladder • Produce 60% of seminal fluid, fluid of semen • Thick, yellow secretion rich in fructose, Vit C, prostaglandins and others – nourish and activate sperm as pass • Joins with vas deferens to form ejaculatory duct • Sperm and seminal fluid enter urethra together

  9. Accessory GlandsProstate • Sits under bladder, encircles upper urethra • Secretes milky fluid helps activate sperm • What happens when enlarged? • Prostate cancer 3rd most common cancer in men

  10. Accessory GlandsBulbourethral Glands • Secrete clear, thick mucus drains into penile urethra • 1st to pass down urethra when man excited • Cleanses urethra of acidic urine and lubricant during intercourse

  11. Semen • Milky white - sperm and gland secretions • Liquid – transport medium for nutrients and chemicals support sperm • Fructose provides most of energy • Alkaline 7.2-7.6 pH to counteract acidity of vagina 3.5-4 pH • Ejaculate is normally 2 to 5 ml, but 50-150 million sperm, acts a dilutant

  12. External Genitalia • Penis – delivers sperm into female reproductive tract • Shaft, glans penis, foreskin • Erectile tissue – fills with blood during excitement - erection • Scrotum – divided sac of skin outside of body, holds testes • Keeps temp at 5.4°F lower than body temp • In cold temp, scrotum shrinks up, SA reduced

  13. Anatomy of Female • More complicated than male – two functions, must produce ova, but also carry and protect fetus. • Ovaries 1° female reproductive organ • Exocrine function – ova • Endocrine function – estrogens and progesterone • Accessory Organs • Transport, nurture, serve needs of reproductive cells or fetus

  14. Ovaries • Ovarian follicles – sac like structures • Each contain immature egg called oocyte • Mature egg in mature follicle is Mature vesicular • Ovulation • Corpus luteum Figure 16.7 Figure 16.8b

  15. Duct SystemFallopian Tubes • Accepts oocyte • Site of fertilization • Supported by ligaments • Enters uterus • Little or no contact with ovary • Fimbriae create currents directing oocyte • Peristalsis and cilia move egg takes 3-4 days • Oocyte viable for 24 hours after ovulation Figure 16.8b

  16. Duct SystemUterus • In women never before pregnant size of pear • Gets very large during pregnancy • 3 layers • Endometrium – fertilized egg burrows in • Myometrium – smooth muscle, labor • perimetrium

  17. Duct System Vagina • Birth Canal • Menstrual flow • Female organ of copulation Figure 16.8a

  18. External Genitalia • Vulva • Mons pubis – fatty area covers pubic symphysis • Labia majora and minora – skin folds • Vestibule – enclosed in labia, contains external openings of urethra and vagina • Greater Vestibular Glands – secretion lubricates vagina during intercourse • Diamond area called perineum Figure 16.9

  19. Mammary Glands • Present in both sexes, usually only active in females • Estrogen at puberty stimulates growth • Function only after reproduction has occurred • Modified sweat glands that are part of skin Figure 16.13

  20. Result of Reproduction

  21. The End

More Related