May 24, 2010Ms. Simon

Regents Biology

Do Now: 1) Pass forward Regents Questions2) Compare the female reproductive systems of birds, amphibians and mammals.

Reproductive SystemsAmphibians Birds MammalsExternal Fertilization Internal Fertilization Internal Fertilization

Most eggs More Eggs Least eggs

External Development of Zygote Internal Development of Zygote

Reproductive and Excretory Systems are Connected Reproductive and ExcretorySeparate

Cloaca Cloaca Vagina

Reproductive Systems

AmphibiansBirds MammalsExternal Development of Zygote (Both) Internal Development of Zygote

External Fertilization Internal Fertilization Internal Fertilization

Reproductive + Excretory Reproductive + Reproductive +

Systems Connected Excretory= Separate Excretory= separate

Less Parental Care More Parental Care More Parental Care

Most Eggs More Eggs Least eggs

Cloaca Cloaca Vagina

AIM: How is the menstrual cycle regulated?

Menstrual Cycle

Function: 1) Prepare the egg for fertilization2) Prepares the uterus to support a fetus

Age: 11-13 up until the mid-50’s (menopause)

Length: Approximately 28 days

During the menstrual cycle, the endometrium (uterine lining) thickensand number of blood vessels increases

Endometrium must:

• Support the fetus• Provide nutrition• Remove Waste

At Day 28, the endometrial wall begins to break down and is shedded from the body in the process of menstruation

At Day 14, an egg is released through ovulation

The menstrual cycle is controlled by the endocrine system

Anterior Pituitary FSH ovary estrogen LH ovary ovulation

Four phases of the menstrual cycle

1) Follicle Phase- low levels of estrogen, stimulate GnRH is released, increase LH + FSH- uterine wall begins to thicken- follicles mature, estrogen levels rise

2) Ovulation- release of an egg

3) Luteal Phase- progesterone, and estrogen are released

4) Menstruation- shedding of the uterine wall

Corpus Luteum