CONCEPTION Mrs. Anthony

VOCAB (reproductive system) Vagina Cervix Fallopian Tubes Uterus Ovaries Ovum Sperm Zygote Conception Embryo Fetus

Female Reproductive Organs

Ovulation Ovulation:1 time every 28 days an ovum (egg cell) is released by one of the two ovaries Usually 1 egg is released Hormones are also released at the same time in order to prepare the uterus in the event that the ovum is fertilized Uterus: an organ where the baby develops during pregnancy (pear shaped) Hysterectomy: Uterus is removed During ovulation the inner lining of the uterus grows & thickens If the ovum is not fertilized by a sperm the lining breaks down & passes out of the body = menstrual period (bleeding) After ovulation an egg is capable of being fertilized for 24-48 hours

Egg Transport The ovum is released from the ovary & moves through the fallopian tube to the uterus This journey takes 2-3 days (It stays in the fallopian tubes waiting to be fertilized for about 24 hours) Muscular contractions takes place, which creates a forward motion transport for the egg to get to the uterus If egg isn’t fertilized it moves down toward uterus and disintegrates, then your body will shed the thick lining of the uterus (menstrual period)

Sperm Transport Sperm must be: Capable of propelling through the environment of a female vagina and cervix The environment must be able to admit the sperm without destroying the sperm The sperm must possess the capability of converting to a form that can penetrate the cell membrane of the egg After ejaculation the sperm form a gel that protects it from the acidic environment of the vagina Once the sperm have entered the uterus, contractions propel the sperm upward into the fallopian tubes. Sperm enter the uterus within minutes after ejaculation Sperm can survive in the reproductive tract for up to five days

Conception cont… If a sperm reaches the fallopian tube, it may penetrate (enter) and fertilize the ovum if there is one to penetrate The process of the sperm fertilizing the ovum is the beginning of conception The fertilized egg stays in the fallopian tube dividing into cells until it makes it way to the uterus The fertilized egg is called a ZYGOTE at this stage Remember the ovum lives for 24-48 hours & sperm can live for 5 days If someone has intercourse on Monday, but ovulation doesn’t take place until Friday conception can still take place) There are about 5-7 days during which intercourse could lead to conception

Implantation An embryo must implant and begin to grow in the uterus In order for this to happen: The fertilized egg is called a ZYGOTE Increases by cell division while it travels to the uterus It multiplies into a ball of cells as it travels The balls of cells then “nest” in the uterus Fertilization + Implantation = Conception Usually takes 6-12 days Ectopic Pregnancy: Fertilized egg doesn’t make it to the uterus to grow and the baby starts to grow somewhere else Does not end in a live birth Very dangerous to the mother

Implantation Cont… Once the zygote attaches to the uterus and has been fertilized for about 4 weeks it is then called an EMBRYO. Some women might notice slight bleeding (spotting) from the baby implanting into their uterus At 9 weeks it is then called a FETUS until the end of pregnancy. In week 1 a hormone is made (hCg) that can be detected in your blood –Doctors can tell A home pregnancy test does not detect the hormone until 3- 4 weeks

Chromosomes & Genes # of births are determined during conception or right after Cells divide= mitosis Identical Twins: when sperm fertilizes the ovum, the cell begins to divide as cells divides the mass of cells may split into ½ creating 2 separate embryo 1 ovum, 1 sperm = twins have very identical characteristics, and are ALWAYS same sex. Fraternal Twins: 2 eggs released from ovaries at the same time & are fertilized by 2 different sperms Twins might not look alike and can be opposite sex Out of 1,000 births: 4 Identical, 23 Fraternal At conception every baby receives 46 chromosomes (23 pairs) 23 from Mother 23 from Father The male determines the sex of the baby

Diagram

Name the parts!

VOCAB (support system for embryo) *Get words from book* Amniotic sac: Amniotic fluid: Placenta: Umbilical Cord: