sign in sign up
<<
Home , Corpus hemorrhagicum, Follicular antrum, Membrana granulosa, Uterine gland

The Female Reproductive System

Ovary Objective

To learn the structure of the , , , , and To learn how these organs contribute to the many functions of the female reproductive system To learn how hormones regulate and/or orchestrate the female reproductive processes Functions of the female reproductive system

• Ova production • Ova and sperm transportation • Microenvironments for fertilization • Implantation and fetal-placental growth • Nourishment and support of offspring • Postnatal repetition

Female Reproductive System

Female Reproductive System Ovary

General structure • Germinal epithelium • Tunica Albuginea • Medulla • Cortex Functional overview Origin of germ cells Germinal epithelium

Cortex

Ovary

Primary Follicle Follicle Maturation

Primordial follicles • Oocyte • Follicular (granulosa) cells

Follicle Maturation

Primary follicle • • Stratum granulosum • Thecal folliculi • Call-Exner bodies Follicle Maturation

• Secondary (antral) follicle: Corona radiata

Follicles

Follicle maturation Graafian follicle

egg Graafian follicle Primordial Follicle

Primordial Follicles

Primary Follicle Zona Pellucida

Primary Follicle

Primary Follicles Primary follicle

http://en.wikipedia.or g/wiki/Call- Exner_bodies Secondary (antral) Follicle

Secondary (antral) follicle

Graafian follicle

Graafian follicle

Ovulation

Rupture of follicle – Mechanism unknown collagenase, protease, plasmins – Not pressure related Oocyte surrounded by zona pellucida & corona radiata – Lost at ovulation in cow – Lost after sperm penetration in most species After ovulation, the develops from remains of the follicular wall after ovulation. Corpus Luteum - yellow body

Corpus hemorrhagicum – transitory structure caused by hemorrhage into ruptured follicle Corpus Luteum - yellow body

Luteinization of granulosa and theca cells to luteal cells

Corpus Luteum - yellow body Granulosa lutein cells - granulosa cells proliferate, hypertrophy, and transform – (Yellow lipid pigment - lutein marks transitory membrana granulosa cells into granulosa lutein cells)

Corpus Luteum - yellow body

(Invasion of stromal cells and vasculature removes clot, deposition of reticular fibers, highly vascularized) Theca lutein cells - lipid producing cells formed from theca folliculi interna Fate relates to pregnancy – If not pregnant: slow regression  – If pregnant: active for all or to various time during pregnancy Ovary

Atresia – Glassy membrane Ovary

Corpus Luteum – Granulosa lutein cells – Theca lutein cells

Corpus Luteum

Corpus Luteum Corpus luteum

– Corpus albicans Hormones orchestrate the process Ovarian Hormones

Androgens – LH stimulation causes theca interna cells to produce androgens (androstenedione and testosterone)

Estrogens – FSH stimulation causes membrana granulosa cells to produce estrogens (estradiol - 17b) • Granulosa cells aromatize androgens from theca interna cells to produce estrogens • Estrogens - induce further proliferation of granulosal cells Ovarian Hormones Inhibition of FSH – Folliculostatin - inhibitory substance has negative feedback on FSH – Steroidsthemselves work through negative feedback - granulosa lutein cells of corpus luteum – development – Maintenance of pregnancy Relaxin - produced by corpus luteum – Causes relaxation of associated with pubic symphysis before partarition - formation and development of ova

Mitosis (oocytogenesis) – oogonia – Prenatal development (ruminants, rodent, swine, human) – Postnatal development (carnivores) Oogenesis - formation and development of ova

Meiosis – oocytes Early development Maturation arrest (dictyate step of meiotic prophase) Later development synchronized with development and maturation of follicles Division • First meiotic division – reduction division – first polar body • Second meiotic division – equational division – second polar body Fertilized 1n Meiosis

Zygote Meiosis (only in spermatogenesis and oogenesis)

Exchange of genetic material in homologous chromosomes (leptotene, zygotene, pachytene, and diplotene steps of development)

Produces haploid condition of gametes Meiosis (only in spermatogenesis and oogenesis)

Produces haploid condition of gametes Species difference in time of polar body formation

Polar body extrusion many mammals horse and dog First preovulation postovulation

Second zona penetration zona penetration of sperm of sperm First polar body Birth Follicular development - synchronized with gamete development

Type Description Germ cell type Primordial flattened follicular primary oocyte cells

Primary low cuboidal primary oocyte follicular cells

Secondary yolk formation primary oocyte zona pellucida theca interna theca folliculi externa Follicular development - synchronized with gamete development (cont’d)

Type Description Germ Cell type Vesicular follicle - Call-Exner bodies primary oocyte (tertiary follicle) (precursors of liquor folliculi) - Formation of - Cumulus oophorus- mound of cells - Corona radiata- adjacent to oocyte nutrients - Stratum granulosum Mature follicle - preovulatory primary/ (graafian follicle) largest, extend secondary from cortex to surface of ovary oocyte Fallopian tube (oviduct or uterine tube)

Segments • Infundibulum with fimbriae • Ampulla • Isthmus • Intramural segment

Fallopian tube (oviduct or uterine tube)

Wall structure and Variation Epithelium • Ciliated cells • Secretory cells Oviduct

Oviduct

Oviduct Oviduct Normal

Lack of estrogen Oviduct Oviduct

Acrosome reacted

Intact

Uterus

General structure: • Zona basalis • Zona functionalis - spiral arteries Zona Functionalis Spiral arteries Proliferative Phase

Phases of the

Overview Menstrual phase: days 1-4 Proliferative phase – Early: days 4-7 – Late: days 7-14 Secretory phase: – Early: days 15-21 – Late: days 21-28 Menstruation Decidual reaction Hormones Orchestrate the Process

Menstruation

Phases of the Menstrual Cycle

Implantation and Fetal-Placental Growth

Implantation and Fetal-Placental Growth Slide 272

Implantation and Fetal-Placental Growth Decidual Reaction

Cervix

Vagina Endocervix – Cervical mucus External os Ectocervix Vagina Structural components Epithelium Endocervix Cervical Mucus

Endocervix ends in the vagina which has no mucus glands

http://women.webmd.com/vaginal- discharge-whats-abnormal Vagina Nourishment and protection of offspring

Nourishment and protection of offspring Other glands of epidermal origin – mammary gland Gland for which our class, mammalia, was named. Mammals are characterized by hair on skin, special ear bones, and in females, milk-producing mammary glands for nourishment of young.

• Http://www.Youtube.C om/watch?V=_44uagj ogyk&feature=fvwrel Leiomyoma Ovary

Ovary

Primordial follicles

Primary follicle

Corpus luteum Female Reproductive System Next time Eye