Fertilization Sperm reaches secondary oocyte and the acrosome helps the sperm to penetrate oocyte cell membrane _

Fertilization Once sperm within oocyte – nucleus of the sperm head swells – forms _ Female meiosis completes only after the sperm enters the egg. Nuclei unite, chromosomes mingle. – Zygote is oocyte and sperm, has 46 chromosomes.

Morula Travel time to uterus: solid ball of about 16 cells called the _____________________. Remains ________________________ in the uterine cavity for three days.

Blastocyst Structure becomes _ Implants in the uterus by _

Organization Blastocysts organizes into – gives rise to the _ Outer cells – become embryonic portion of _ Embryo until _ Fetus until _

Placenta Placenta develops attaches the embryo to uterine wall – exchanges _ – – wastes between maternal blood and embryonic blood. Placenta also _

Hormone changes In non pregnant female, – the corpus luteum degenerates uterine lining sloughs off In pregnant female, need to _

HCG HCG: human chorionic gonadotropin. prevents _ HCG and some of the embryonic cells – – continues to _ – – inhibits _

HCG HCG secretion is high for ____________________________ and then declines. Corpus luteum ________________________________, but is most important in the first few months before the _

More hormones Placental lactogen – stimulates __________________________________ and prepares the mammary glands for milk secretion. – hormone from _ – Inhibits the ________________________________ in the myometrium, ___________________________________ until birth. – ______________________________________ of the symphysis pubis and SI joints aids passage of fetus through birth canal.

More hormones Increased secretion of _______________________________ and of parathyroid hormone Aldosterone from adrenal cortex – promotes renal _ –. PTH helps to maintain high concentrations of calcium.

Parturition Pregnancy continues for about ____________________________ and ends with ______________________ or birth.

Hormonal changes with birth – no longer preventing uterine contractions __________________________ stimulate ______________________ to contract.

Labor Contractions start at the ________________________________ and travel downward, forcing the contents toward the cervix. Labor contractions force the fetal head against the cervix – – elicits a reflex _

Dilation of cervix Dilation of cervix stimulates increased release of oxytocin  more contractions.

Involution After the birth, the _ expelled by the remaining uterine contractions, – stimulated by _

Involution For _________________________ the uterus undergoes _ – which is the _ For several weeks – will pass a _ – then a _ – until the ______________________________ and returns to a non-pregnant state.

Mammary glands Mammary glands: – ______________________________ specialized to secrete milk following pregnancy. composed irregularly shaped lobes Each lobe contains – – _______________________________________ that leads to the nipple and opens to the outside.

More hormones (breast) During pregnancy, placental estrogen and progesterone stimulate mammary development. – Estrogen: – Progesterone

More hormones (breast) Prolactin, released in _________________ and present throughout pregnancy. Prolactin causes _

Milk production and secretion The _____________________________________. No longer will inhibit prolactin. Prolactin stimulates the mammary glands to secrete large quantities of milk – not until two or three days following birth Until then, there is _

Milk ejection Milk must be _ When the breast is _ – release of _ – causes the muscles to contract and eject the milk.

Milk production Prolactin is released as long as milk is removed from the breasts. If milk not removed regularly, – prolactin is inhibited –

Birth Control: – the ______________________________ of the number of offspring produced and _ Contraception: – method designed to _____________________________ of an egg following intercourse or _

Withdrawing the penis from the vagina before ejaculation – Natural family planning. – Requires _ – More effective when coupled with _ Wake up in the morning, without getting out of bed, take temperature. Body temp rises ½ degree following ovulation. Dips just a bit before

Cervical mucus Cervical mucus will become When the mucus is stretchy, it _____________________ through which the sperm can travel to reach the egg

Mechanical barriers Condom _ Female condom: – inserted into the vagina. Blocks semen from reaching the cervix. __________________________: Cup shaped structure with a flexible ring forming the rim. – inserted into the vaginal canal and _ – Prevent entry of sperm into cervix. Must be properly fitted. – Best used with a _

Mechanical barriers ________________________: smaller than diaphragm. – Inserted before intercourse. – Have been made from _

Chemical barriers Includes _ Will create an environment that is unfavorable for sperm cells. – Have ______________________________. Most effective when coupled with the barrier methods.

Contraceptives Oral contraceptives: – contains _ – Disrupts the gonadotropin secretion and ________________________________________ that would normally trigger ovulation – interfere with _ May cause nausea, water retention, increased pigmentation of skin, breast tenderness. Also liver damage, and some controversy surrounding breast cancer.

IUD Intrauterine devices: physician places IUD within _ IUD may be expelled, produce pain, excessive bleeding. May _

Vaginal Ring releases a continuous _ The ring is inserted into the vagina _ A new ring is used with each cycle.

Vaginal Ring Disadvantages – increased _ – vaginal _ – cannot use a diaphragm or cervical cap for a backup method of birth control

Patches place a thin plastic _________________________________ of the buttocks, stomach, upper outer arm, or upper torso once a week for _ releases combined hormones that protect against pregnancy for one month

Patches Disadvantages – ______________________ at the site of application – – for wearers of contact lenses, a change in vision or the inability to wear the lenses – may not be as effective for women who weigh more than 198 pounds

Surgical methods – Physician removes a small _______________________________ near the epididymis and _ – May result in pain for a week or so. Sperm cannot leave the epididymis, and are therefore _ Tubal ligation: – __________________________________________ so that sperm cells cannot reach an egg cell.