Copyright © 2006, Elsevier Inc. All rights reserved C HAPTER 2 The female reproductive system

Copyright © 2006, Elsevier Inc. All rights reserved

CHAPTER 2The female reproductive system


FIGURE 2-1 SIDE VIEW OF THE FEMALE PELVIC REGION SHOWING SOME MAJOR COMPONENTS OF THE REPRODUCTIVE SYSTEM.


FIGURE 2-2 (A) A DIAGRAMMATIC SECTION THROUGH THE UTERUS AND OVIDUCTS. (B) AN ENLARGEMENT OF THE BOX IN (A) SHOWING THE STRUCTURE OF THE UTERINE WALL.


FIGURE 2-3 SECTION THROUGH THE OVARY SHOWING ITS COMPONENT PARTS.


FIGURE 2-4 PHOTOMICROGRAPH OF A REGION FROM A HUMAN TERTIARY FOLLICLE SHOWING THE OOCYTE SURROUNDED BY FOLLICULAR (GRANULOSA) CELLS. THE LOWER LEFT CORNER SHOWS SOME CELLS OF THE THECA.


FIGURE 2-5 STEROIDOGENESIS WITHIN THE OVARY. CONVERSION OF PREGNENOLONE TO DHEA, THEN FURTHER SYNTHESIS OF OTHER ANDROGENS AND ESTROGENS, IS THE 5 PATHWAY, PREDOMINANT IN OVARIAN FOLLICLES. CONVERSION OF PREGNENOLONE TO PROGESTERONE AND THEN TO ANDROGENS AND ESTROGENS IS THE 4 PATHWAY, PREDOMINANT IN THE CORPUS LUTEUM. SPECIFIC ENZYMES ARE REQUIRED FOR EACH ARROW. DOUBLE ARROWS MEAN THAT CONVERSION CAN GO IN EITHER DIRECTION


FIGURE 2-6 CHEMICAL STRUCTURES OF THREE STEROID HORMONES. NOTE THAT ALTHOUGH THESE MOLECULES ARE ALL DERIVED FROM CHOLESTEROL AND DIFFER ONLY SLIGHTLY IN STRUCTURE, THEY HAVE QUITE DIFFERENT ACTIONS ON TISSUES


FIGURE 2-7 STEROIDOGENESIS IN THE TERTIARY AND PREOVULATORY FOLLICLE AND IN THE CORPUS LUTEUM AFTER OVULATION. NOTE THAT THE TERTIARY FOLLICLE FOLLOWS THE 5 PATHWAY, PRODUCING MOSTLY ESTRADIOL IN THE BLOOD. IN CONTRAST, THE PREOVULATORY FOLLICLE (I.E., A GRAAFIAN FOLLICLE AFTER THE LH SURGE BUT BEFORE OVULATION) AND THE CORPUS LUTEUM PRODUCE A LARGE AMOUNT OF PROGESTERONE AND SOME ESTRADIOL, AND THUS FOLLOW THE 4 PATHWAY OF STEROIDOGENESIS.


FIGURE 2-8 THE PROCESS OF OOGENESIS, WHICH IS NOT COMPLETED UNTIL A SPERM PENETRATES AN OVULATED EGG.


FIGURE 2-9 DIAGRAMS ILLUSTRATING OVULATION. THE STIGMA (A) RUPTURES (B) AND THE OVUM IS EXPELLED ALONG WITH FOLLICULAR (ANTRAL) FLUID (B AND C). THE OVULATED OVUM IS ARRESTED IN THE SECOND MEIOTIC DIVISION (D) UNTIL IT IS PENETRATED BY A SPERM


FIGURE 2-10 USUAL AND UNUSUAL POSITIONS OF THE UTERUS. (A) THE UTERUS IS IN THE USUAL ANTEFLEXED POSITION, WHEREAS (B) THE UTERUS IS TILTED BACKWARD IN A RETROFLEXED POSITION.


FIGURE 2-11 THE FEMALE EXTERNAL GENITALIA, OR VULVA


FIGURE 2-12 SECTION THROUGH THE ADULT FEMALE MAMMARY GLAND.


FIGURE 2-13 DIAGRAMMATIC VIEW OF A SINGLE MAMMARY ALVEOLUS. MILK IS SECRETED BYEPITHELIAL SECRETORY CELLS INTO A CAVITY (LUMEN) WITHIN THE ALVEOLUS. FROM HERE, THE MILK IS CARRIED TO THE NIPPLE THROUGH A SERIES OF DUCTS. THE BLOOD SUPPLY TO THE ALVEOLUS IS IMPORTANT BECAUSE OF ITS SUPPORT OF ALVEOLUS GROWTH AND SECRETION. ALSO, THE BLOOD CARRIES HORMONES TO THE ALVEOLUS THAT STIMULATE ITS SECRETION AND CAUSE CONTRACTION OF THE MYOEPITHELIAL CELLS, LEADING TO MILK EJECTION.


FIGURE 2-14 INFLUENCE OF TIMING OF FIRST BIRTH AND NULLIPARITY ON INCIDENCE OF BREAST CANCER. WOMEN WHO FIRST GAVE BIRTH BEFORE AGE 30 HAVE A LOWER RATE OF BREAST CANCER THAN NULLIPAROUS WOMEN.


FIGURE 2-15 HOW TO EXAMINE THE BREASTS AS A METHOD TO DETECT ABNORMAL LUMPS AND OTHER CHANGES. (MODIFIED WITH PERMISSION OF THE AMERICAN CANCER SOCIETY.)

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Copyright © 2006, Elsevier Inc. All rights reserved C HAPTER 2 The female reproductive system