REPRODUCCIÓN. La idea fija. Copyright 2004 Pearson Education, Inc., publishing as Benjamin Cummings

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1 REPRODUCCIÓN La idea fija

2 How male and female reproductive systems differentiate The reproductive organs and how they work How gametes are produced and fertilized Pregnancy, stages of development, birth & lactation Reproductive and developmental maturation and aging

3 Sex Determination: Overview Dimorphism: Males sperm Females eggs Chromosomes Autosomes Sex Chromosomes X - chromosome Y - chromosome Figure 26-1: Human chromosomes

4 Sex Determination: Overview Figure 26-2: Inheritance of X and Y chromosomes

5 Sexual Differentiation: Internal Embryonic Development Bipotential tissues: genes & hormones direct differentiation: Sex-determining Region Y Testis Determining Factor Gonad testis or ovary Wolffian duct Vas deferens, Mullerian duct oviduct

6 Sexual Differentiation: Internal Embryonic Development Figure 26-3a: Sexual development in the human embryo

7 Pathway for Sexual Development: Review for Genes to Organs Figure 26-4: Role of the SRY gene in male development

8 Sexual Differentiation: External Genitalia Bipotential tissues: genital tubercle, urethral folds, urethral groove and labioscrotal swellings

9 Sexual Differentiation: External Genitalia Figure 26-3b: Sexual development in the human embryo

10 Determination of sex Determined genetically by two sex chromosomes: XY or XX. Y is dominant and codifies the testis-determining gene product. Only one X is active. The other X condenses to form the Barr body.

11 Regulation of Reproduction: General Pathways Hypothalamus: pulse generator Gonadotropin releasing H (GnRH) Anterior Pituitary Lutenizing H (LH) Follicle stimulating H (FSH) Ovary: progesterone Estrogen, inhibin Testis: testosterone, inhibin

12 Regulation of Reproduction: General Pathways Figure 26-7: General pattern of hormonal control of reproduction

13 Hypothalamus-Pituitary-Gonadal Axis GnRH Hypothalamus GnRH Testosterone LH FSH Anterior Pituitary Oestrogen LH FSH Inhibin Inhibin Androgenic and anabolic effects Leydig Cells Sertoli Cells Testis Gonads Stimulatory Inhibitory Ovary Oestrogenic effects Theca interna Granulosa Androgens

15 Male Reproductive Components Testis => spermatozoa; testosterone production Epididymis => spermatozoa maturation & storage Ductus deferens & ampulla => transport & semen Accessory glands => semen a) Prostate gland b) Vesicular glands (seminal vesicles) c) Bulbourethral (Cowper s) gland Urethra => transport Penis=> transport and ejaculation

16 Male Reproductive Anatomy and Physiology Seminal vesicles Figure 26-9a: ANATOMY SUMMARY: Male Reproduction

17 Semen

19 Spermatogenesis: Sperm Production in the Testis Seminiferous tubules Spermatids Spermatocytes Spermatozoa Sertoli cells Interstitial tissue Leydig cells Capillaries

20 Spermatogenesis: Sperm Production in the Testis Figure 26-9b-e: ANATOMY SUMMARY: Male Reproduction

21 Cells of Leydig Produce Androgens Interstitial cells mainly (of Leydig) Testosterone

22 Seminiferous Tubule and Interstitial Cells

23 Regulation of Spermatogenesis Figure 26-11: Hormonal control of spermatogenesis

24 Regulation of Spermatogenesis GnRH LH Leydig cells testosterone 2 0 sex charact. GnRH FSH Sertoli cells spermatoctye maturation Inhibin feedback FSH, testosterone short & long loops

29 Female Reproductive Anatomy and Physiology: Overview Ovary Fallopian tube Fimbriae Uterus Cervix Endometrium Vagina Clitoris Labia

30 Female Reproductive Anatomy and Physiology: Overview Figure 26-12b: ANATOMY SUMMARY: Female Reproduction

31 Ovary: Details of Histology & Physiology Follicle Oocytes Thecal cells Granulosa cells Estrogen Corpus luteum Corpus luteum Progesterone Inhibin

32 Ovary: Details of Histology & Physiology Figure 26-12d: ANATOMY SUMMARY: Female Reproduction

33 Ovary: Details of Histology & Physiology Figure 26-12d: ANATOMY SUMMARY: Female Reproduction

34 Ovary: Details of Histology & Physiology Follicle Oocytes Thecal cells Androgens Granulosa cells Estrogens Corpus luteum Corpus luteum Progesterone Inhibin Folículos ováricos Región medular Región cortical

35 Ovary: Details of Histology & Physiology

36 Follicular Structure

37 Menstrual Cycle: Egg Maturation, and Endometrial Growth Follicular phase Egg matures Ovulation Egg released Luteal phase Corpus luteum Endometrium Prep for blastocyst No Pregnancy Menses Figure 26-13: The menstrual cycle

38 Figure The Hormonal Regulation of the Female Reproductive Cycle Figure 28.26a-c

39 The Hormonal Regulation of Ovarian Activity ovulación Figure 28.25

Follicular Growth Regulation GnRH rises in response to a decline in inhibin and sex steroids GnRH stimulates rise in pituitary FSH & LH secretion.

40 Follicular Growth Regulation GnRH rises in response to a decline in inhibin and sex steroids GnRH stimulates rise in pituitary FSH & LH secretion. FSH stimulates new follicle growth LH induces thecal cell growth, vascularization & androgen synthesis FSH stimulates granulosa cell production of E2 & LH receptor

41 Follicular Growth Regulation 2 LH act on thecal & granulosa cells and FSH acts on granulosa cells Late follicular phase has elevated follicular fluid E2, P, FSH and LH but low androgens

42 Endocrine Control of Menstrual Cycle: Follicular Phase FSH stimulates follicular development Estrogen: + feedback, limits more follicles

43 Endocrine Control of Menstrual Cycle: Ovulation Estrogen LH "surge" & FSH spike egg release Inhibin pushes FSH down, new follicle development

44 Ovulation The stigmata, a coneshaped protrusion of the follicle wall, appears just before ovulation Preovulatory follicular fluid has elevated E2, P, FSH, LH, oxytocin, plasmin activity & collaginase activity Extensive follicular vascularization occurs immediately prior to ovulation

45 Endocrine Control of Menstrual Cycle: Follicular Phase and Ovulation Figure 26-14a,b: Hormonal control of the menstrual cycle

46 Endocrine Control of Menstrual Cycle: Luteal phase Granulosa cells form corpus luteum E2, progesterone progesterone & estrogen maintain endometrium Inhibin continues to limit new follicular development

47 Corpus Luteum Development 1 LH stimulates thecal & granulosa cell invasion of follicular cavity LH induces the luteinization of both cell types P synthesis increases as number of luteal cell increase

48 Corpus Luteum Development 2 LH stimulates increased P & E secretion FSH has no direct role in corpus luteum (CL) maintenance CL function depends on adequacy of follicle development (adequate induction by FSH of E2, LH and LDL receptor levels) Failure of adequate CL function results in luteal insufficiency

49 Corpus Luteum Development 3 Estrogen induces luteolysis Luteolysis causes decreased E2 & P secretion leading to decreased plasma levels Luteolysis continues in the absence of a fertilized ovum

50 Endocrine Control of Menstrual Cycle: Late Luteal phase Pregnancy: maintain progesterone, estrogen & inhibin No pregnancy: progesterone, estrogen & inhibin Menses, FSH & LH new follicle development

51 Endocrine Control of Menstrual Cycle: Luteal phase and Late Luteal phase Figure 26-14c, d: Hormonal control of the menstrual cycle

52 The Uterine Cycle Figure 28.20

53 Menstrual Cycle: Egg Maturation, and Endometrial Growth Follicular phase Egg matures Ovulation Egg released Luteal phase Corpus luteum Endometrium Prep for blastocyst No Pregnancy Menses Figure 26-13: The menstrual cycle

54 Overview of the Menstrual Cycle

SISTEMA REPRODUCTOR (LA IDEA FIJA) Copyright 2004 Pearson Education, Inc., publishing as Benjamin Cummings

SISTEMA REPRODUCTOR (LA IDEA FIJA) How male and female reproductive systems differentiate The reproductive organs and how they work How gametes are produced and fertilized Pregnancy, stages of development,