Chapter 23: The Male and Female Reproductive Systems

Overview

Key Terms corpus luteum luteinizing hormone (LH) progesterone endometrium menopause semen estrogen menses spermatozoon follicle menstruation (pl., spermatozoa) follicle-stimulating ovary testis (pl., testes) hormone (FSH) ovulation testosterone gamete ovum (pl., ova) uterus infertility

Reproduction Learning Outcome Identify the male and female gametes and state the purpose of meiosis.

Reproduction Asexual One-celled organisms Divide themselves Sexual Males and females Specialized sex cells (germ cells or gametes) Male are spermatozoa (sperm cells) Female are ova (egg cells)

Meiosis Cell division process Halves the number of chromosomes in cell Produces gametes Human gametes have 23 chromosomes

The Male Reproductive System Learning Outcomes 2. Name the gonads and accessory organs of the male reproductive system and cite the function of each. 3. Describe the composition and function of semen. 4. Draw and label a spermatozoon.

The Male Reproductive System Two groups of organs Primary Gonads (testes) Accessory Ducts Exocrine glands

Figure 23-1 Male reproductive system. What four glands empty Secretions into the urethra? What duct receives secretions from the epididymis?

The Testes Located outside the body proper Scrotum Inguinal canal Spermatic cord

Figure 23-2 Descent of the testes. 11

Internal Structure Specialized tissue in testis Seminiferous tubules Sustentacular cells Interstitial cells

Figure 23-3 Microscopic view of the testis. Where are the interstitial cells located? 13

Testosterone Male sex hormone functions Develops and maintains reproductive structures Develops spermatozoa Develops secondary sex characteristics Deeper voice Broader shoulders Narrower hips More muscle tissue More body hair

The Spermatozoa Individual cells manufactured in seminiferous tubules Head Nucleus Acrosome Midpiece Mitochondria Tail (flagellum)

Figure 23-4 Human spermatozoon. What organelles provide energy for sperm cell motility? 16

✓ The Male Reproductive System Checkpoints 23-1 What is the process of cell division that halves the chromosome number in a cell to produce a gamete? 23-2 What is the male gamete called? 23-3 What is the male gonad? 23-4 What is the main male sex hormone? 23-5 What are the main subdivisions of a spermatozoon? 17

Accessory Organs System of ducts that transports spermatozoa Tubules Epididymis Ductus deferens (vas deferens) Seminal vesicle Ejaculatory duct

Semen Mixture of sperm and secretions from various organs Seminal vesicles Prostate gland Bulbourethral glands (Cowper glands) Functions: Nourish spermatozoa Transport spermatozoa Neutralize acidity of male urethra and female vagina Lubricate reproductive tract during intercourse Prevent infection with antibacterial enzymes and antibodies

The Urethra and Penis Urethra Carries urine from bladder Carries reproductive cells outside body Penis Corpus spongiosum Corpus cavernosum Glans penis Prepuce (foreskin)

Figure 23-5 Cross-section of the penis. What subdivision of the penis contains the urethra? 21

Ejaculation Reflex centers in spinal cord initiate process Smooth muscle contraction in prostate Skeletal muscle contraction in pelvic floor Forceful expulsion of semen through urethra to outside

✓ The Male Reproductive System Checkpoints 22-6 What is the order in which sperm cells travel through the ducts of the male reproductive system? 22-7 What glands, aside from the testis, contribute secretions to semen? 23

Hormonal Control of Male Reproduction Learning Outcome 5. Identify the two hormones that regulate the production and development of the male gametes.

Hormonal Control of Male Reproduction Anterior pituitary produces hormones that control testes Follicle-stimulating hormone (FSH) Promotes spermatozoa formation Luteinizing hormone (LH) Stimulates testosterone development Aids sperm cell development

✓ Hormonal Control of Male Reproduction Checkpoint 22-8 What two pituitary hormones regulate both male and female reproduction? 26

The Effects of Aging on Male Reproduction Decreasing Testosterone production Spermatozoa production Prostate secretions Seminal vesicle secretions

Disorders of the Male Reproductive System Learning Outcome 6. Discuss disorders of the male reproductive system.

Disorders of the Male Reproductive System Infertility Sterility Oligospermia (tubule damage) X-rays Infections Toxins Malnutrition Vasectomy

Structural Disorders Cryptorchidism Torsion of testis Hernia Phimosis

Figure 23-6 Torsion of the testis. 31

Infections Sexually transmitted infection (STI) spread through sexual contact Chlamydia Gonorrhea Genital herpes Syphilis Epididymitis Prostatitis Orchitis

Tumors Prostate tumors Can be benign or malignant Most common cancer of men in United States Testicular tumors

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✓ Disorders of the Male Reproductive System Checkpoint 22-9 What are some infectious diseases of the male reproductive tract? 35

The Female Reproductive System Learning Outcome 7. Name the gonads and accessory organs of the female reproductive system and cite the function of each.

The Female Reproductive System Ovaries (female gonads) Uterus Passageways Oviduct (fallopian tube or uterine tube) External genital organs

Figure 23-8 Female reproductive system. What is the deepest part of the uterus called? The most inferior portion? 38

The Ovaries Located in pelvic abdomen Held by ligaments Attached to uterus and body wall

Figure 23-9 Microscopic view of the ovary. 40

The Ova and Ovulation Ovarian follicle (graafian follicle) Holds ripening ova Secretes estrogen Ruptures to discharge egg cell (ovulation) Oviduct Tube that leads to uterus

The Corpus Luteum Formed from remains of follicle after ovum is expelled Secretes estrogen and progesterone Usually shrinks and is replaced by scar tissue Remains active during pregnancy

Accessory Organs Uterine tubes Uterus Vagina Greater vestibular glands Vulva and perineum

Figure 23-10 Female reproductive system (sagittal section). Which has the more anterior opening, the vagina or the urethra? 44

The Uterine Tubes Extend from near ovary to uterus Not connected to ovary Fimbriae produce current that sweeps ova into oviduct Cilia in tube lining and peristalsis of tube move ova

Figure 23-11 The uterus in microscopic view. In which part of the menstrual cycle is the endometrium most highly developed? 46

The Uterus Organ in which fetus develops to maturity Corpus Body Cervix Neck Fundus Supporting ligaments Myometrium Muscular wall Endometrium Specialized epithelium lining

The Vagina Distal part of birth canal that opens to outside of body Fornix Posterior fornix Cul-de-sac (rectouterine pouch or pouch of Douglas) Hymen Greater vestibular (Bartholin) glands

The Vulva and the Perineum External parts of female reproductive system Vulva Labia Clitoris Related structures Obstetrical perineum

Figure 23-12 External parts of the female reproductive system. 50

✓ The Female Reproductive System Checkpoints 23-10 What is the female gamete called? 23-11 What is the female gonad called? 23-12 What structure contains each ovum? 23-13 What is the process of releasing an ovum from the ovary called? 23-14 What does the follicle become after its ovum is released? 23-15 In what organ does a fetus develop? 51

The Menstrual Cycle Learning Outcome 8. List in the correct order the hormones produced during the menstrual cycle and cite the source of each.

The Menstrual Cycle Controlled by pituitary hormones regulated by hypothalamus Cyclic pattern Regulated by hormonal feedback Averages 28 days

Figure 23-13 The menstrual cycle. What ovarian hormone peaks closest to ovulation? What ovarian hormone peaks after ovulation? 54

Beginning of the Cycle Several follicles in ovary begin to develop Increased production of estrogen Thickens endometrium Elongates uterine secretion glands Inhibits release of FSH Stimulates pituitary to release LH

Ovulation LH surge in blood Causes ovulation Transforms ruptured follicle into corpus luteum that produces estrogen and progesterone Endometrium thickens Glands and blood vessels increase in size FSH and LH are inhibited

The Menstrual Phase If ovum is not fertilized, corpus luteum degenerates Estrogen, progesterone levels decrease Endometrium degenerates, produces menstrual flow Endometrium begins to repair itself FSH released from anterior pituitary

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✓ The Menstrual Cycle Checkpoints 23-16 What are the two hormones produced in the ovaries? 23-17 On what day does ovulation occur in a 28-day menstrual cycle? 59

Menopause Learning Outcome 9. Describe the changes that occur during and after menopause.

Menopause Menstruation ceases Normal ovarian function declines Follicles stop ripening No appreciable amounts of estrogen produced Uterus, oviducts, vagina, vulva become somewhat atrophied Vaginal mucosa becomes thinner, dryer, more sensitive

Hormone Replacement Therapy Combination of estrogen with synthetic progesterone prescribed to relieve menopause discomfort Increases breast cancer risk Increases thrombosis and embolism risk Risks increase with duration of therapy

✓ Menopause Checkpoint 23-18 What is the definition of menopause? 63

Birth Control Learning Outcome 10. Cite the main methods of birth control in use.

Birth Control Hormonal methods for women Male contraceptive pill still under investigation Barrier methods Mifepristone (RU486) (morning-after pill) for emergency contraception Fertility awareness

Figure 23-14 Surgical sterilization. 66

Figure 23-15 Insertion of a female condom. 67

Checkpoint 23-19 What is the definition of contraception? ED: Please add title. Checkpoint 23-19 What is the definition of contraception? 68

Disorders of the Female Reproductive System Learning Outcome 11. Discuss disorders of the female reproductive system.

Disorders of the Female Reproductive System Disorders That Can Contribute to Infertility Menstrual disturbances Tumors Infections

Menstrual Disorders Amenorrhea—absence of menstrual flow Dysmenorrhea—painful or difficult menstruation Abnormal uterine bleeding Premenstrual syndrome (PMS) Endometriosis

Figure 23-16 Possible sites of endometriosis. 72

Benign and Malignant Tumors Fibroids Breast cancer Mammogram to detect Endometrial cancer Ovarian cancer Cervical cancer Linked with human papillomavirus Papanicolaou test to detect

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Figure 23-17 Mammogram. 75

Infections Sexually transmitted infections Chlamydia Gonorrhea HIV and genital herpes Syphilis Genital warts Salpingitis Pelvic inflammatory disease (PID)

Figure 23-18 Pathway of infection. Do the pathways show an ascending or descending infection? 77

Infertility Learning Outcome 12. Discuss possible causes of infertility in men and women.

Infertility More difficult to diagnose and evaluate in women Infections Endocrine disorders Psychogenic factors Abnormal structure and function of reproductive organs

✓ Infertility Checkpoint 23-20 What is the definition of infertility? 80

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Case Study Learning Outcome 13. Referring to the case study, discuss some procedures used to diagnose and treat uterine disorders. 82

Word Anatomy Learning Outcome 14. Show how word parts are used to build words related to the reproductive systems. 83

Word Anatomy Word Part Meaning Example semin/o semen, seed Sperm cells are produced in the seminiferous tubules. fer to carry The ductus deferens carries spermatozoa away from (de-) the testis. crypt/o hidden Cryptorchidism refers to an undescended testis (orchid/o). ov/o egg An ovum is an egg cell. men/o uterine bleeding Amenorrhea is absence of menstrual flow. mast/o breast A mastectomy is surgical removal of the breast. salping/o tube Salpingitis is inflammation of a tube, such as the uterine tube.

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