This is what you should have learned in high school about reproduction, from Jim Buckley, Edwards-Knox Central School, Russell, New York.  Try Mr. Buckley's quiz on human reproduction for his high school students.

If you don't have your textbook, here is the Reproductive System from the On-line Biology book.

to learn more about the human Reproductive System, go to HUMAN ANATOMY On-Line.

ASEXUAL REPRODUCTION in INVERTEBRATES

1. FISSION

• protists [Fig. 39.1a]
• longitudinal fission in planarians [Fig. 39.1b];
• constrictions in annelids [Fig. 39.1c]

2. BUDDING

• hydras [Fig. 39.1d]

3. FRAGMENTATION

• flatworms, echinoderms, sponges [Fig. 39.1e]

4. PARTHENOGENESIS

• certain rotifers, flatworms, aphids, fish, lizards

ADVANTAGES OF ASEXUAL REPRODUCTION

DISADVANTAGES OF ASEXUAL REPRODUCTION

SEXUAL REPRODUCTION

• gametes
• zygote

External Fertilization

Internal Fertilization

• copulation; intromittent organ; internal development [Fig. 39.2]
• hermaphrodite (monoecious)

Reproductive Timing

• melatonin

PATTERNS OF VERTEBRATE REPRODUCTION

• fish, amphibians, reptiles, birds, mammals

Human Reproduction

When you are finished with this section, test your knowledge with the Human Reproduction Problem Set from the University of Arizona Biology Project

HUMAN MALE REPRODUCTIVE SYSTEM [Fig. 39.4]

• male reproductive organs from Berkeley High School
  1. testes [Fig. 39.5]: produce sperm and testosterone
  2. scrotum
  3. conducting tubes
  4. accessory glands
  5. penis

PRODUCTION OF SPERM IN TESTES [Fig. 39.5]

• seminiferous tubules: site of spermatogenesis

Path of Sperm [Fig. 39.4]

• epididymis to vas deferens to ejaculatory duct to urethra in penis

Penis

• cavernous bodies (corposa cavernosa)

Semen Production

1. seminal vessicles
2. prostate gland
3. Cowper's glands (bulbourethral glands)

MALE HORMONAL CONTROL [Fig. 39.6; Table 39.1]

androgens: male sex hormones

1. hypothalamus gonadotropin releasing hormone (GnRH); stimulates anterior pituitary
2. anterior pituitary LH (controls production of testosterone in males) and FSH (promotes spermatogenesis in males w/testosterone)
3. testes: interstitial cells stimulated to produce male sexual hormone testosterone; influences male sexual characters - beard, voice, bone growth, sperm production (w/FSH)

HUMAN FEMALE REPRODUCTIVE SYSTEM [Fig. 39.7]

• Female Reproductive Organs from Berkeley High
  • female gonads
    1. ovaries [Fig. 39.8]: produce ova and hormones
  • Accessory organs
    2. oviducts: uterine tube (fallopian tube) [Fig. 39.9]
    3. uterus (womb) [Fig. 39.10]
       • endometrium
    4. cervix
    5. vagina
  • external genital structures
    1. clitoris
    2. labia minora
    3. labia majora
    4. vulva

HORMONAL REGULATION of REPRODUCTION [Table 39.2, 39.3]

Ovarian Cycle [Fig. 39.7]

Uterine (Menstrual) Cycle [Fig. 39.11, 39.12]

A.    first day: menstruation: shedding of endometrium + blood, tissue, other fluids

B.    14th day: ovulation

1. 1. Preovulatory Phase
   1. FSH (from pituitary) stimulates follicle to develop
      1. follicle: ova plus surrounding cells - makes estrogen
   2. estrogen: stimulates growth of endometrium
2. mid-cycle
       surge of estrogen stimulates hypothalamus to stimulate pituitary to secrete LH
       which causes
       maturation of follicle, ovulation, & development of corpus luteum
   1. ovulation: stimulated by FSH and LH from anterior pituitary
   2. follicle: produces ovum
   3. corpus luteum (yellow body): remains in ovary after ovulation; controlled by LH
   4. ovum
3. Postovulatory Phase
   1. corpus luteum releases estrogen & progesterone; inhibits LH and FSH production; stimulates thickening of endometrium (esp. progesterone)
   2. egg not fertilized no implantation:
      1. corpus luteum degenerates (as a result of fall of LH & FSH)
      2. estrogen and progesterone decrease
      3. arteries in uterine wall constrict; cells die causing menstruation
   3. return to preovulatory phase; pituitary secretes FSH again

Fertilization [fig 39.13-15]

Introduction to the Birth Control Problem Set from the University of Arizona Biology Project

1. occurs in upper uterine wall from one sperm only
2. embryo implants in uterine wall formation of placenta
3. placenta: 
   1. secretes human chorionic gonadotropin (HCG) which causes the
   2. corpus luteum to continue to function 
   3. LH secretion ceases
   4. progesterone secreted by corpus luteum (as well as estrogen) prevents menstruation
   5. after 3rd month corpus luteum degenerates, but placenta secretes estrogen & progesterone.

Birth Control - Contraception

• Protecting Against Unintended Pregnancy: A Guide to Contraceptive Choices from the U.S. Food and Drug Administration web site offers information about the many methods of contraception.
• How much do you know about birth control?  Take the Birth Control Problem Set from the The Biology Project, University of Arizona
  

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