1. The Menstrual Cycle What’s Happening?

2. Hormones Involved FSH (follicle stimulating hormone) = released by the pituitary gland > signals ovaries to mature an ova (inside a follicle). FSH (follicle stimulating hormone) = released by the pituitary gland > signals ovaries to mature an ova (inside a follicle). LH (leutenizing hormone) = released to signal ovaries to produce estrogen. LH (leutenizing hormone) = released to signal ovaries to produce estrogen. FSH & LH are released into the bloodstream which will cause the follicles to begin maturing. FSH & LH are released into the bloodstream which will cause the follicles to begin maturing.

3. Hormones Estrogen = as follicles mature, more and more estrogen is being produced to thicken the lining of the uterus. Also causes the cervical mucous to change. Estrogen = as follicles mature, more and more estrogen is being produced to thicken the lining of the uterus. Also causes the cervical mucous to change. LH = a surge of the LH hormone will cause a mature follicle to ‘burst’ open and release an egg > OVULATION. LH = a surge of the LH hormone will cause a mature follicle to ‘burst’ open and release an egg > OVULATION. Progesterone = causes the uterine lining (endometrium), to become covered with mucous. Progesterone = causes the uterine lining (endometrium), to become covered with mucous.

4. The Cycle 1-5 Days = FSH and LH into bloodstream. 1-5 Days = FSH and LH into bloodstream. 5-13 Days = Endometrium being built up. Ova is maturing. 5-13 Days = Endometrium being built up. Ova is maturing. 14-15 Days = Ovulation occurs 14-15 Days = Ovulation occurs 15-27 Days = Endometrium waits for fertilized ova. 15-27 Days = Endometrium waits for fertilized ova. 27-30 Days = Endometrium will shed if ova is not fertilized > menstruation. 27-30 Days = Endometrium will shed if ova is not fertilized > menstruation.

5. Fertilization and Development Zygote = fertilized ovum Zygote = fertilized ovum Blastocyst = ball of cells with a cavity in the center. Blastocyst = ball of cells with a cavity in the center. Embryo = implanted blastocyst. Embryo = implanted blastocyst. Amniotic sac = fluid-filled sac that surrounds the embryo. Protects embryo from outside impact and temperature changes. Amniotic sac = fluid-filled sac that surrounds the embryo. Protects embryo from outside impact and temperature changes.

6. Development Placenta = structure that forms along the lining of the uterus as the embryo implants. Transfers oxygen and nutrients from the mother’s blood to the embryo’s blood through the umbilical cord (connects embryo to mother’s placenta). Embryo’s waste also travels through the umbilical cord. Placenta = structure that forms along the lining of the uterus as the embryo implants. Transfers oxygen and nutrients from the mother’s blood to the embryo’s blood through the umbilical cord (connects embryo to mother’s placenta). Embryo’s waste also travels through the umbilical cord.

7. Development Fetus = the developing baby from the end of the eighth week. At this point it is recognizable as a human being. Fetus = the developing baby from the end of the eighth week. At this point it is recognizable as a human being.