Reproduction Sections 6.6 – 11.4

Female Reproductive System 6.6.1 Draw and label diagrams of the adult male and female reproductive systems 6.6.2 Outline the role of hormones in the menstrual cycle, including FHS, LH and estrogen and progesterone. 6.6.3 Annotate a graph showing hormone levels in the menstrual cycle, illustrating the relationship between changes in hormone levels and ovulation, menstruation and thickening of the endometrium. 11.4.4 Annotate a diagram of the ovary to show the location and function of germinal epithelium, primary follicles, mature follicle and secondary oocyte. 11.4.5 Outline the process involved in oogenesis within the ovary, including mitosis, cell growth, the two divisions of meiosis, the unequal division of the cytoplasm and the degeneration of the polar body

6.1.1 Draw and label diagrams of the adult male and female reproductive systems.

Major vestibular (Bartholin’s) gland Labia minora Labia majora Figure 46.10 Oviduct Ovary Uterus (Urinary bladder) (Pubic bone) (Rectum) Urethra Cervix Body Vagina Glans Clitoris Prepuce Major vestibular (Bartholin’s) gland Labia minora Labia majora Vaginal opening Oviduct Ovaries Figure 46.10 Reproductive anatomy of the human female. Follicles Corpus luteum Uterus Uterine wall Endometrium Cervix Vagina

Female Reproductive System

Major vestibular (Bartholin’s) gland Labia minora Labia majora Figure 46.10a Oviduct Ovary Uterus (Urinary bladder) (Pubic bone) (Rectum) Urethra Cervix Body Vagina Figure 46.10 Reproductive anatomy of the human female. Glans Clitoris Prepuce Major vestibular (Bartholin’s) gland Labia minora Labia majora Vaginal opening

Posterior Pituitary The posterior lobe (neurohypophysis) releases hormones produced by neurosecretory cells of the hypothalamus These cells extend from the hypothalamus into the posterior lobe and release hormones into the bloodstream in response to nerve signals An example of a hormone released from the posterior pituitary is anti-diuretic hormone (ADH) and Oxytocin.

Anterior Pituitary The hypothalamus synthesizes hormones called releasing factors, which are released into the portal vein that extends to the anterior lobe The releasing factors cause endocrine cells in the anterior pituitary to release specific hormones into the bloodstream to act on distant cells An example of a releasing factor is GnRH, which triggers the release of LH and FSH from the anterior pituitary

6.6.2 Outline the role of hormones in the menstrual cycle, including FSH, LH and estrogen and progesterone Pituitary Hormones: FHS (Follicle Stimulating Hormone) stimulates these changes: Development of the oocyte in the follicle (follicle contains the oocyte) Thickening of the follicle wall Secretion of follicular fluid Secretion of estrogen by follicle wall LH (Leutenizing Hormone) stimulates these changes: Completion of meiosis in the oocyte Partial digestion of the follicle wall allowing it to burst open (ovulation) Growth of the corpus luteum which secretes estrogen and progesterone

OVULATION

Estrogen- secreted by the developing follicles: Thickening of endometrium Blood vessels growth in the endometrium Increase in FSH receptors in follicle Inhibition of FSH secretion and stimulation of LH secretion estrogen levels are high Progesterone released from the corpus leutium, causes these changes maintenance of thickening of the endometrium with many blood vessels Inhibition of FSH and LH

6.6.3 Annotate a graph showing hormone levels in the menstrual cycle, illustrating the relationship between changes in hormonal levels and ovulation , menstruation and thickening of the endometrium

Degenerating corpus luteum Figure 46.13 (a) Control by hypothalamus Inhibited by combination of estradiol and progesterone Hypothalamus  Stimulated by high levels of estradiol 1 GnRH  Anterior pituitary Inhibited by low levels of estradiol  2 FSH LH (b) Pituitary gonadotropins in blood 6 LH FSH 3 FSH and LH stimulate follicle to grow LH surge triggers ovulation (c) Ovarian cycle 7 8 Growing follicle Corpus luteum Degenerating corpus luteum Maturing follicle Follicular phase Ovulation Luteal phase Estradiol secreted by growing follicle in increasing amounts Progesterone and estradiol secreted by corpus luteum 4 (d) Ovarian hormones in blood Peak causes LH surge (see ) 5 6 Figure 46.13 The reproductive cycle of the human female. 10 Estradiol 9 Progesterone Estradiol level very low Progesterone and estra- diol promote thickening of endometrium (e) Uterine (menstrual) cycle Endometrium Menstrual flow phase Proliferative phase Secretory phase Days 5 10 14 15 20 25 28

Figure 46.13a 1. Reproduction begins with release of GnRH which stimulates the anterior pituitary to release FSH and LH (a) Control by hypothalamus Inhibited by combination of estradiol and progesterone Hypothalamus  Stimulated by high levels of estradiol  1 GnRH Anterior pituitary Inhibited by low levels of estradiol  Figure 46.13 The reproductive cycle of the human female. 2 FSH LH 2. FSH and LH Release

Degenerating corpus luteum Figure 46.13b (b) Pituitary gonadotropins in blood 6 LH FSH 3 FSH and LH stimulate follicle to grow LH surge triggers ovulation (c) Ovarian cycle 7 8 Figure 46.13 The reproductive cycle of the human female. Corpus luteum Degenerating corpus luteum Growing follicle Maturing follicle Follicular phase Ovulation Luteal phase Days 5 10 14 15 20 25 28

3. FS stimulates the follicle growth aided by LH 4 3. FS stimulates the follicle growth aided by LH 4. the cells of growing follicles begin to make estradiol. 5. when estradiol secretion by the growing follicle begins to rise steeply, 6. the FSH and LH levels increase Low levels of estradiol inhibits the secretion GnRH and High level increase release of GnRH (positive feedback) 7. The maturing follicle, containing a fluid filled cavity, enlarges, forming a bulge near the surface of the ovary. The follicle phase ends with ovulation [about a day after the spike], releasing the secondary oocyte

Luteal phase: after the release of the oocyte, LH triggers the follicle to the transformed into corpus luteum, a glandular structure. The corpus luteum secreted progesterone and estradiol which leads to negative feedback on the hypothalamus and pituitary – thus preventing the stimulation of another egg Eventually LH and FSH levels drop, GnRH drops and this leads to the degeneration of the corpus luteum Degeneration in the corpus luteum triggers the reduction in estradiol and progesterone which leads to the cycle beginning again Endometrium is sloughed away (menstruation) No longer inhibited, FSH can start menstrual cycle again If fertilization of egg occurs, the zygote releases a hormone (hCG) which maintains the corpus luteum

Estradiol secreted by growing follicle in increasing amounts Figure 46.13c Estradiol secreted by growing follicle in increasing amounts Progesterone and estradiol secreted by corpus luteum 4 (d) Ovarian hormones in blood Peak causes LH surge (see ) 6 5 10 9 Estradiol Progesterone Estradiol level very low Progesterone and estra- diol promote thickening of endometrium (e) Uterine (menstrual) cycle Figure 46.13 The reproductive cycle of the human female. Endometrium (e) Menstrual flow phase Proliferative phase Secretory phase Days 5 10 14 15 20 25 28

11.4.5 Outline the process involved in oogenesis within the ovary, including mitosis, cell growth, the two divisions of meiosis, the unequal division of the cytoplasm and the degeneration of the polar body Oogenesis describes the production of female gametes (ova) within the ovary The process begins during fetal development, when a large number of cells (oogonia) are formed by mitosis before undergoing a period of growth These cells begin meiosis but are arrested in prophase I until puberty At puberty, some follicles continue to develop each month is response to FSH secretion These follicles complete the first meiotic division to form two cells of unequal size

The cell with less cytoplasm is a polar body (which degenerates), while the larger cell forms a secondary oocyte The secondary oocyte begins the second meiotic division but is arrested in prophase II (until fertilization) It is released from the ovary (ruptured follicle develops into corpus luteum) and, if fertilization occurs, will complete meiosis (5:42) The second meiotic division will produce an ovum and a second polar body

11.4.4 Annotate a diagram of the ovary that show the location and function of: Germinal epithelium Primary follicles Mature follicle Secondary ooctye

The ovary contains follicles in various stages of development Egg cells within primordial follicles have been arrested in prophase I and have yet to undergo meiotic division Egg cells within mature follicles have begun meiotic division and are released from the ovary as secondary oocytes (arrested in prophase II) The ruptured follicle develops into a corpus luteum that will, in time, degenerate into a corpus albicans The germline epithelium functions as an epithelial layer separating ovarian tissue from the rest of the body - it is not involved in oocyte development

Male Reproductive System 6.6.1 Draw and label diagrams of the adult male and female reproductive systems 6.6.4 List three roles of testosterone 11.4.1 Annotate a light micrograph of the testis tissue to show the location and the function of the interstitial cells (Leydig), germinal epithelium cells, developing spermatozoa 11.4.2 Outline the process involved in spermatogenesis within the testis including: mitosis, cell growth, the two divisions of meiosis, and cell differentiation. 11.4.3 State the role of LH, testosterone and FSH in spermatogenesis. 11.4.6 Draw and label a diagram of mature sperm and egg 11.4.7 Outline the role of the epididymis, seminal vesicles and the prostate gland in the production of semen.

Seminal vesicle (behind bladder) Figure 46.11a Seminal vesicle (behind bladder) (Urinary bladder) Prostate gland Bulbourethral gland Urethra Erectile tissue of penis Figure 46.11 Reproductive anatomy of the human male. Scrotum Vas deferens Epididymis Testis

(Urinary bladder) Seminal vesicle (Urinary duct) (Rectum) (Pubic bone) Figure 46.11b (Urinary bladder) Seminal vesicle (Urinary duct) (Rectum) (Pubic bone) Vas deferens Erectile tissue Ejaculatory duct Figure 46.11 Reproductive anatomy of the human male. Prostate gland Urethra Penis Bulbourethral gland Vas deferens Glans Epididymis Testis Prepuce Scrotum

6.6.4 List three roles of testosterone Pre-natal development of male genitalia Development of secondary sex characteristics Maintenance of sex drive (libido) Anabolic activity leads to increase body mass

11.4.2 Outline the process involved in spermatogenesis within the testis including: Mitosis Cell growth Meiosis (both phases) Cell differentiation Spermatogenesis (5:38): https://www.youtube.com/watch?v=krSMZDsjLuU

These haploid cells then differentiate to form sperm cells Spermatogenesis describes the production of spermatozoa (sperm) in the seminiferous tubules of the testes The first stage of sperm production requires the division of germline epithelium by mitosis These cells (spermatogonia) then undergo a period of growth This is followed by two meiotic divisions that result in four haploid daughter cells These haploid cells then differentiate to form sperm cells The developing sperm cells are nourished throughout by the Sertoli cells

Sperm production “Germ Cells” Spermatogonoia (2n) mitosis Primary spermatocyte meiosis I Secondary spermatocyte(1n) meiosis II Spermatids (Spermatozoa) Maturation produces spermatozoa (1n gametes) (50- 500 million sperm/ejaculation)

11.4.1 Annotate a light micrograph of the testis tissue to show the location and the function of the Interstitial cells (Leydig cells) - produce the male sex hormone, testosterone  Germinal epithelium: germ cells, spermatogonia (2n), divides by mitosis to make 1⁰ spermatocytes. Germ cells will divide by meiosis to make spermatozoa) Developing spermatozoa Sertoli cells – nourish developing spermatozoa

Testes 40X magnification

A. Spermatozoa (mature spermatocytes) B. Spermatogonium C. Provides Nourishment for the developing cell D. produce the male sex hormone, testosterone 

11.4.3 State the role of LH, Testosterone and FSH in spermatogenesis LH:  Stimulates the interstitial cells (Leydig cells) to produce testosterone FSH:  Stimulates the (first) meiotic division of spermatogonia Testosterone:  Stimulates the (second) meiotic division of spermatogonia and the maturation of spermatozoa through differentiation

 Hypothalamus GnRH   Anterior pituitary FSH LH Negative feedback Figure 46.14  Hypothalamus GnRH   Anterior pituitary FSH LH Negative feedback Negative feedback Sertoli cells Leydig cells Figure 46.14 Hormonal control of the testes. Inhibin Spermatogenesis Testosterone Testis

11.4.6 Draw and label a diagram of a mature sperm and egg Figure 46.12ac 11.4.6 Draw and label a diagram of a mature sperm and egg Neck Tail Midpiece Head Plasma membrane Acrosome Nucleus Figure 46.12 Exploring: Human Gametogenesis Mitochondria

11.4.7 Outline the role of each in regards to production of semen: Epididymus Seminal vesicles Prostate gland

Testicular fluids are removed, concentrating the sperm Epididymis Testicular fluids are removed, concentrating the sperm Sperm mature and develop the ability to swim It stores the sperm for 2–3 months. Final maturation is completed in the female reproductive tract. A. Head of epididymis, B. Body of epididymis, C. Tail of epididymis, and D. Vas deferens

Seminal Vesicle Adds nutrients (including fructose) for respiration Secretes prostaglandins, causing contractions to the female system and helping sperm move towards the egg Prostate Gland Secretes alkaline fluid which neutralizes vaginal acids (changes pH from 4 to 6 which aids sperm motility)

Neck Tail Midpiece Head Plasma membrane Acrosome Nucleus Mitochondria Figure 46.12ac Neck Tail Midpiece Head Plasma membrane Acrosome Nucleus Figure 46.12 Exploring: Human Gametogenesis Mitochondria

11.4.8 Compare the process of spermatogenesis and oogenesis including the number of gametes and the timing of the formation and release of gamets.