Chapter 8 Unit 2 National Geographic – in the womb Prenatal Development Chapter 8 Unit 2 National Geographic – in the womb

Bell Ringer What are some things that you already know about how a baby develops during pregnancy? http://www.thepregnancytester.com/

Ovulation The mature ovum (egg) is released by the ovary about once a month. The egg travels through the fallopian tube where it is either fertilized by the male reproductive cell (within 24 hrs) or passed out of the uterus during menstruation Count backwards 14 days from when your next period is supposed to start, and that is when you should be ovulating

Conception Day 1 Male and female reproductive cells unite

Octo Mom Prenatal Development 37-42 week Count from the first day of your last period Divided into 3 Trimesters Octo Mom

First trimester 3 Forms of Pregnancy Zygote Embryo Fetus 1-13 Weeks Size goes from a pin head to about 3 inches

Period of the Zygote First two weeks before the fertilized egg reaches the uterus Starts as a single cell but divides to about 500 cells that form a tiny, fluid filled ball Zygote grows to be about the size of a pin head

Period of the Embryo Week 1-9 video From the time of implantation into the uterine wall through about the eighth week of pregnancy (2 weeks to 2 months) Three layers of cells form: Ectoderm Mesoderm Endoderm Week 1-9 video

Three Layers of Cells Ectoderm Mesoderm Endoderm Outer layer of cells that become the skin, hair, and nails. Also forms the nervous system, including the brain, spinal cord, and nerves. Mesoderm Middle layer that becomes the bones, muscles, blood vessels, and some internal organs such as the heart, kidneys, and reproductive organs Endoderm Internal cell layer, eventually becomes the other internal organs such as the stomach, liver, and lungs

Embryo - The embryo grows rapidly during this time and several important and amazing changes occur: -Major organs form(heart, lungs, bones, muscles. These are not ready to function yet and will continue to develop. Amniotic sac and fluid formed Attachments of umbilical cord to uterus Midway through the first trimester the embryo has grown to the size of a small raisin, 2 more weeks a grape

The Support System Amniotic Fluid Placenta Umbilical cord Fills the protective amniotic sac which cushions the developing baby from outside pressures Placenta Attached to the uterine wall and contains a network of blood vessels Umbilical cord Connects the baby to the placenta through which blood flows carrying nutrients and oxygen. Also carries wastes from the baby.

First Month Cell multiplication begins Egg attaches to uterus lining The heart, which is no larger than a poppy seed, has begun beating.

First Month

Two Months The embryo is about ¼” inch long and has distinct, slightly webbed fingers. Veins are clearly visible. The heart has divided into right and left chambers. Bones begin to form Development of internal organs The embryo is attached to the mother by the umbilical cord.

Two Months

Period of the Fetus Fetus is the third and last period of pregnancy. Begins about the eighth week (end of 2 months) and lasts until birth. Fetus is “Young One” in Latin because the fetus resembles a miniature baby that has everything it needs, but still needs time to develop and mature before birth.

The Fetus 9 weeks until birth At the beginning major organs are present but still forming The heartbeat flutters rapidly Bones begin to form and muscles start to develop Week 10-14

Fetus 12 weeks

Three Months By now the fetus is 1 inch long and is fully formed. All organs and muscles have formed but are immature. Eye lids fused. Fingers and toes almost complete

The end of the First Trimester 3 inches long and weighs about 1 ounce Ears and eyes move close to their final positions The liver produces bile and kidneys produce urine The fetus can open and close its moth and form tiny fists

Second Trimester 4 to 6 months Grow to 2 pounds during this time period Eyebrows and eyelashes appear Lanugo Fine hair covers the fetus’s skin Fat tissue forms Video Week 21-27

Second Trimester Quickening Prenatal thumb sucking (5 months) Fetus can move around and kick Mother begins to feel these movements Prenatal thumb sucking (5 months)

2nd trimester Lungs “breath” and swallow amniotic fluid Taste, touch, smell, sight and hearing develop Fetus can hear sounds including mothers heartbeat Eyes open and close 18-20 weeks can determine a baby’s sex 15 to 20 weeks

Four Months Fetus is 3 inches long Can suck thumb, swallow, hiccup and move. Facial features are clearer.

4 months

Five Months Fetus is 8-10” long weighing almost a pound. Lanugo develops Fetus is more active Hair, eyelashes, and eybrows appear

Six Months Baby's lungs are filled with amniotic fluid, and he has started breathing motions. If you talk or sing, he can hear you. Fat deposits under skin Vernix develops

6 Months

Third Trimester 7th-9th month Fetus triples its weight Vital fat tissue Brain and systems continue to develop Fetus sleeps and may dream The bones of the skull are still somewhat soft to allow the fetus to pass through the birth canal Video 28-37 Weeks

Seven Months By the end of the seventh month, your baby weighs about 1 1/2 -2lbs and is about 10-12 inches long. Fetus is active, then rests.

7 Months

Eight Months Your baby is gaining about half a pound per week, and layers of fat are piling on. He has probably turned head-down in preparation for birth. Fetus may react to noise with jerking actions.

8 months

Nine Months Your baby is a hefty 6 to 9 pounds and measures between 19 and 22 inches. As he becomes more crowded, you may feel him move around less. Disease-fighting antibodies are taken in from mother’s blood Fetus “drops” into pelvis and is ready for birth

9 Months Called Lightening The lungs develop in preparation fro breathing and the head is now head-down. The last few weeks, the baby “drops” in preparation for delivery – giving the mother a little breathing space. Called Lightening 9 Months

Almost time! Birth weight of 7.5 pounds is average Head accounts for ¼ weight

Pregnancy is broken up into Trimesters FIRST Trimester (1-3 Months) Ovum (a female egg) Zygotic & Embryonic period of Development When all organs, nerve and brain cells Develop SECOND Trimester (4-6 Months) “Golden Trimester” when Mother feels the best Third Trimester (7-9 Months) Baby’s organs and body systems mature Baby gains weight

“Where I Started” Booklet Crafty & Creative Time! “Where I Started” Booklet

Activity Using your notes and page 172 of your text Make flash cards 1 side describe the fetus at various stages 1 side have 1st, 2nd, or 3 trimester Include a specific time frame: ie 1-2 weeks, 8 months etc.

From the mom’s view

Developing Child page 145 Jot down the effects on the mom month by month Fill in any missing info you have on the babies side

Journal What are some new facts you have learned about prenatal development?

Prenatal Time Line Choose one month of prenatal development to describe (mothers perspective as well) Bullet point maid developments At least 2 images