Life Story of the Unborn The ins and outs of pregnancy

Main Ideas The beginning of human life begins with the fertilization of an egg cell by a sperm cell. During pregnancy, a fetus develops at a predictable rate and according to a predictable sequence.

What do you know??? What is the main difference between sex cells and other cells in the body? What are male sex cells called? What are female sex cells called? What process results in the formation of sex cells? What is the name of the process in which a sperm and an egg cell unite?

Before You Were You htm htm Let’s read page 517 in our books and see what happens as the zygote and embryo begin to grow.

Your Early Development B. your heart beat began to beat-by 22 days B. your heart beat began to beat-by 22 days D. Leg and arm stumps appeared-end of first month. D. Leg and arm stumps appeared-end of first month. K. Your face and neck began to develop- 2 nd month K. Your face and neck began to develop- 2 nd month I. Your sex was clearly indicated by internal sex organs- end of 2 nd month I. Your sex was clearly indicated by internal sex organs- end of 2 nd month A Your fingers and toes took shape-end of 2 nd month A Your fingers and toes took shape-end of 2 nd month G. Your baby teeth started to take shape, and tiny buds for your permanent teeth began to develop-3 rd month G. Your baby teeth started to take shape, and tiny buds for your permanent teeth began to develop-3 rd month J. You developed fingerprints -4 th month J. You developed fingerprints -4 th month F. Your mother was aware of your movement-4 th month F. Your mother was aware of your movement-4 th month E. Your eyes could respond to light-7 th month E. Your eyes could respond to light-7 th month C. Your memory began-7 th month C. Your memory began-7 th month H. You began the cycle of sleeping and waking, and you developed the ability to dream -8th month H. You began the cycle of sleeping and waking, and you developed the ability to dream -8th month

Embryo Pictures ment_pictures_slideshow/article.htm ment_pictures_slideshow/article.htm

First Trimester -Episode 1- Fertilization and the first month Once the sperm reaches the egg, the egg changes its surface to not allow more sperm in. Once the two nuclei unite they will have how many chromosomes? Cell division can now occur. Read page 519 silently and jot down notes of important steps that occur in the first month of pregnancy.

First Trimester - Episode 1 After 1 week =cell has a diameter of half of a millimeter. By week 3 =cell has a diameter of 2.5 millimeters ___

In vitro Fertilization Discussion and Debate  Read the materials provided for in vitro fertilization and take a stance, are you for it or against it.  Test Tube babies: What are the pros and cons of each side?  Should there be a cut off of what you can determine about your unborn child?

TWINS *** TWINS

***TWINS*** If only one sperm can get through the membrane of an egg, how are twins formed? Twins are formed when there is a “malfunction” in the reproduction system. There is still only one sperm to one egg.

***TWINS*** Two Types:  Identical Twins: their outward characteristics are exactly the same.  The one egg divides into two zygotes and share one placenta

***TWINS*** Two Types  Fraternal Twins: outward characteristics could be very similar or could only have their birthday the same.  When two eggs are released by one ovary two separate sperm can fertilize the two eggs. Twins develop in separate zygotes.

***TWINS*** About 70% of all twins are fraternal and 30% of all twins are identical. The development of fraternal twins is hereditary, it skips every other generation. The development of identical twins is not hereditary, its cause is not known.

Share Your Opinions Should a female drink alcohol while pregnant? Should a female smoke while pregnant? Should a female use any other drug during pregnancy, including aspirin? How does stress of a pregnant women effect her unborn child?

Websites to Gather Info smoking-during-pregnancy-affects-you- and-your-baby_ bc smoking-during-pregnancy-affects-you- and-your-baby_ bc ls/14332_1170.asp ls/14332_1170.asp reg_stress.htm reg_stress.htm

Episode 2-The Second Month A period of very rapid growth.

First Trimester-2 nd Month Embryo grows about 5 times longer and about 500 times heavier. Your face and neck developed Your brain begins to develop at a faster rate than any other organ. Internal sex organs begin to grow Your stumps will now begin to grow into limbs

First Trimester- 2 nd Month After eight weeks the embryo is about 2.5 cm long and weighs about 1 gram One dime or one paper clip is equal to 1 gram.

First Trimester-3 rd Month Now called a fetus Sexual development occurs rapidly “tooth month” first teeth start to take shape tiny buds for permanent teeth develop Vocal cords form Digestive system, liver, and kidneys all began to function Bones and muscles begin to develop and your face and body begin to take their distinct human form

First Trimester- 3 rd Month Placenta – the organ that develops within the uterus, that allows nutrients and wastes to be exchanged between the mother and the embryo. Let’s check out p. 524 in your books to read about placentas

2 nd Trimester- Months th Month5 th Month6 th Month

2 nd Trimester- 4 th Month Take a look at p. 526 to see what happens during the beginning of the second trimester. In the Description Chart write some important “landmarks” of a child’s development in the 4 th, 5 th, and 6 th months.

2 nd Trimester 4 th Month  Face looks “human”  Hair appears on the head  Most bones are recognizable  Stretching movements occur  External sex organs appear 5 th Month  Nose bones begin to harden  Lungs are formed but do not function  Gripping reflex of the hands begins to develop  Kicking movements and hiccupping may be felt by the mother.

2 nd Trimester 6 th Month  Colon becomes recognizable  Nostrils open  Cerebral cortex of the brain is layered in a more typically adult fashion.  The internal organs occupy their normal positions.  Thumb sucking may begin  By the end of the 2 nd Trimester the baby is about 36 cm long and has a mass of 850 grams

The Final Trimester The third trimester is a time of refining the organs and the life processes that were formed throughout the time in the womb. Highlighted next will be some major milestones in each of these months prior to being born.

The Third Trimester The Seventh Month:  Fetus is lean, wrinkled, and red  Eyelids open, eyebrows and eye lashes form  Fetus practices controlled breathing and swallowing movements.  Retinal layers of the eye are complete and light can be perceived.

The Third Trimester Eighth Month:  Sense of taste is present  Weight increases slowly  Fat is collecting, wrinkles are smoothing and the body is rounding out.

Third Trimester Ninth Month  Nails reach the fingertips  Lungs are about two-third complete they do not work completely until birth  Baby begins to move itself so that its head is facing downwards, so the baby is not breached.

Birth Birth occurs about nine months after conception. Now lets watch a movie to see just how a baby is born….