1. The Male and Female Reproductive Systems

2. Overview

3. Sexual Reproduction Requires males and females
Two major functions of the reproductive system are to produce offspring and to provide the experience of pleasure through physical intimacy.
Specialized sex cells (germ cells or gametes)
Male cells are spermatozoa (sperm cells).
Female cells are ova (egg cells).
Gametes produced by meiosis
Results in gametes with half the normal chromosome number
Male and female gametes combine to produce cell with normal chromosome number

4. Functions of the Male Reproductive System
Male external genitalia include the penis and scrotum.
The penis serves to eliminate urine from the bladder and functions to deposit sperm in the female reproductive tract for the purposes of reproduction.
The scrotum regulates the temperature and protects the testes from trauma.
Manufacture spermatozoa
Deliver spermatozoa to the female in semen

5. The Male Reproductive System
Fig. 20-1

6. Male Internal Reproductive Organs
The testes and ductal system compose the man's internal reproductive tract.
Spermatogenesis occurs in the testes, and the ductal system serves as the exit route for sperm from the man's body.
Sperm are formed in the seminiferous tubules and mature in the epididymis

7. Spermatozoa Pathway Testes Epididymis
Coiled tube located on the surface of the testis
Temporarily stores sperm cells
Ductus deferens
Ampulla (enlarged portion)
Ejaculatory duct
Urethra

8. Male Reproductive Exocrine Glands
Seminal vesicle
Twisted muscular tube posterior to urinary bladder
Produces nourishing, alkaline secretion containing simple sugars, an energy source for sperm.
Prostate gland
Located inferior to the urinary bladder
Alkaline secretion neutralizes vaginal acidity
Bulbourethral glands (Cowper glands)
Located in the pelvic floor inferior to the prostate
Secrete mucus to lubricate the urethra and penis tip

9. Functions of Semen Nourishes spermatozoa Transports spermatozoa
Neutralizes the acidity of the male urethra and female vagina
Lubricates the reproductive tract
Prevents infection

10. The Penis What subdivision of the penis contains the urethra?
Fig. 20-2
What subdivision of the penis contains the urethra? 10

11. The Penis (cont.) Parts Corpus spongiosum
Glans penis: distal enlargement
Prepuce
Removed by circumcision
Contains urethra
Corpora cavernosa
Erection: blood spaces in corpora fill with blood
Ejaculation: semen passes through urethra

12. The Testes Contained in scrotum
In fetus, descends through inguinal canal
Suspended by the spermatic cord
Internal structure
Seminiferous tubules
Sustentacular cells
Interstitial cells
Fig. 20-3C

13. The Testes (cont.) Where are the interstitial cells located?
Fig. 20-3A and B
Where are the interstitial cells located? 13

14. A Spermatozoon Production begins at puberty Acrosome: contains enzymes
Flagellum: propels sperm
Fig. 20-4
What organelles provide energy for sperm cell motility? 14

15. ✓ The Male Reproductive System (Review) Checkpoints
20-1 What is the process of cell division that halves the chromosome number in a cell to produce a gamete?
20-2 What is the male gamete called?
20-3 What is the male gonad?
20-4 What is the structure on the surface of the testis that stores sperm?
20-5 What glands, aside from the testis, contribute secretions to semen?
20-6 What are the main subdivisions of a spermatozoon? 15

16. Hormonal Control of Male Reproduction (cont.)
Testicular Activity
Controlled by two hormones from the anterior pituitary
Follicle-stimulating hormone (FSH)
Luteinizing hormone (LH)
Testosterone
Functions:
Development and maintenance of the male reproductive accessory organs
Development of spermatozoa
Development of secondary sex characteristics

17. Regulation Which hormone stimulates testosterone secretion—LH or FSH?
Fig. 20-5 17

18. ✓ Hormonal Control of Male Reproduction (Review) Checkpoints
20-7 What two pituitary hormones regulate both male and female reproduction?
20-8 Which cell type in the testis produces the main male sex hormone? 18

19. The Effects of Aging on Male Reproduction
Decrease in testosterone and spermatozoa production
Decline in sperm motility and quality
Erectile dysfunction
Benign prostatic hypertrophy (BPH)

20. Female Reproductive System
Fig. 20-6A
What is the deepest part of the uterus called? The most inferior portion? 20

21. Female Reproductive System (cont.)
Fig. 20-6B 21

22. Accessory Organs: The Uterus
Pear-shaped muscular organ in which fetus develops and matures
Three regions
Body (corpus)
Cervix (neck)
Fundus
Three layers
Peritoneum (perimetrium)(protective cover)
Myometrium(muscle layer)
Endometrium (lining)

23. Accessory Organs Uterine tubes (oviducts or fallopian tubes)
Muscular structure extending from the uterus to a point near the ovary
The fallopian tubes lead from the uterus toward the ovaries.
The isthmus is the narrow portion near the uterus.
The ampulla is the middle portion, and the infundibulum is the outer portion close to the ovaries.
Fimbriae- make wave-like motions over the ovary to guide the released ovum toward the fallopian tube.

24. Accessory Organs
The vagina is an internal reproductive organ that functions as the female organ for sexual intercourse, exit point for the menstrual flow, and as the birth canal. Rugae, or folds, allow for stretching during the birth process.
Fornix
Posterior fornix
Rectouterine pouch
Hymen

25. Accessory Organs (cont.)
The greater vestibular glands (Bartholin)
Secrete mucus into the vestibule
Provide lubrication
External genitalia (vulva)
Labia (labia majora and labia minora)
Clitoris
Mons pubis

26. The External Genitalia
Fig. 20-7 26

27. The Ovaries and Ova Ovaries are located in the pelvic cavity
Ovaries produce ova
Ovarian follicle:
Protects ovum
Produces ovarian hormones
Ovaries contain gametes at birth.

28. The Ovary
Fig. 20-8 28

29. ✓ The Female Reproductive System (Review) Checkpoints
20-9 What is the female gamete called?
20-10 What is the female gonad called?
20-11 In what organ does a fetus develop?
20-12 In what structure does an ovum mature? 29

30. The Female Reproductive Cycle
Controlled by pituitary hormones LH and FSH, which are regulated by the hypothalamus
Cyclic pattern of hormonal activity
Each cycle begins with menstruation
One cycle averages 28 days
Ovulation (release of ovum) separates cycle into into preovulatory (follicular) and postovulatory (luteal) phases

31. Reproductive Cycle
What ovarian hormone peaks closest to ovulation? What ovarian hormone peaks after ovulation?
Fig. 20-9 31

32. The Female Reproductive Cycle: Preovulatory Phase
Several follicles enter final stages of maturation
Increased production of estrogen
Prepares the endometrium
Elongates uterine secretory glands
Proliferative phase in the uterus
Inhibits release of FSH

33. The Female Reproductive Cycle: Ovulation and the Postovulatory Phase
LH surge in blood
Causes ovulation
Transforms ruptured follicle into corpus luteum that secretes estrogen and progesterone
Endometrium continues to thicken
Glands and blood vessels increase in size
Secretory phase in the uterus
FSH and LH are inhibited via estrogen and progesterone feedback

34. Menstruation If ovum is not fertilized, corpus luteum degenerates
Estrogen, progesterone levels decrease
Endometrium degenerates, produces menses
Endometrium begins to rebuild
The decrease of estrogen and progesterone levels allows increased release of FSH from the anterior pituitary

35. Regulation of Reproductive Function
Menstrual cycle
Recurring changes that take place in a woman’s reproductive tract associated with menstruation and the events that surround menstruation
Menstruation
The casting away of blood, tissue, and debris from the uterus as the inner lining sheds
Flow lasts 4 to 6 days (on average)
Blood loss: 25 to 60 mL
Can contribute to low iron stores and anemia

36. Regulation of Reproductive Function
The sexual response cycle is divided into four phases: excitement, plateau, orgasm, and resolution.
Vasocongestion and myotonia are the primary physiologic processes that contribute to sexual response in both the male and female.

37. ✓ The Female Reproductive Cycle (Review) Checkpoints
20-13 What are the two hormones produced in the ovaries?
20-14 What process releases an ovum from the ovary?
20-15 What does the follicle become after its ovum is released? 37

38. Contraceptive Methods
Surgical
Hormonal (Female)
Barrier
Other
Tubal ligation
Birth control pills
Male condom
Spermicide alone
Vasectomy
Birth control shot
Female condom
Fertility awareness
Birth control patch
Diaphragm (with spermicide)
Birth control ring
Contraceptive sponge (with spermicide)
Intrauterine device

39. Birth Control Artificial means to prevent fertilization of the ovum
Surgical sterilization
Tubal ligation (female)
Vasectomy (male)
Hormonal methods for women
Male contraceptive pill still under investigation
Mifepristone (RU-486) (morning-after pill) is a drug taken after conception to terminate an early pregnancy
Male and female condoms

40. Male and Female Condoms
Fig 40