1 PSIO 202: Lecture 38 Female Reproduc9ve System: Coordina9on of Cycles
Objectives • Tortora pp. 1160-1165 Objectives • Describe the hormonal signals that coordinate oogenesis and preparation of the uterine wall. • Understand how the two cycles---ovarian and uterine---are temporally coordinated.
Female Reproductive Cycle • Controlled by monthly cycle of hormones from anterior pituitary, hypothalamus and ovary • Consists of coordinated monthly cycle of changes in the ovary and uterus • Ovarian cycle – changes in the ovary during and after maturation of the oocyte • Uterine cycle – preparation of the uterus to receive fertilized ovum – if implantation does not occur, the stratum functionalis is shed during menstruation
Estrogens Progesterone and estrogens Corpus luteum Ovulation Mature (graafian) follicle Secondary follicle Primary follicles Primordial follicles LH FSH Hypothalamus GnRH Anterior pituitary Corpus albicans Luteal phase Follicular phase Menstrual phase Preovulatory phase Ovulation Postovulatory phase (a) Hormonal regulation of changes in the ovary and uterus Stratum functionalis Stratum basalis Ovarian cycle Uterine (menstrual) cycle Days Corpus Hemor- rhagicum
Menstrual Phase • Menstruation lasts for ~5 days • First day is considered beginning of 28 day cycle • In ovary ~20 follicles that began to develop 6 days before are now beginning to secrete estrogen – fluid is filling the antrum from granulosa cells • In uterus – declining levels of progesterone causes spiral arteries to constrict and glandular tissue degenerates – stratum functionalis layer is sloughed off along with 50 to 150 ml of blood
You've reached the end of your free preview.
Want to read all 15 pages?
- Spring '08
- progesterone, corpus luteum, Ovulation, Secretion