children the early years chapter 4…pregnancy 1 1
TRANSCRIPT
Children The Early YearsChapter 4…Pregnancy
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Pregnancy
o Pregnancy is the process through which a new human prepares to enter the world.
oBegins when the baby is created inside the mother’s body.
o Lasts about 9 months.
oGrowth is rapid, it is affected by the genes of both parents
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Conception
http://www.babycenter.com/2_inside-pregnancy-fertilization_10354435.bc
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oCell…The smallest unit of life that is able to reproduce itself.
oSperm…The male sex cell.
oOvum…The female sex cell or egg.
oZygote…The single cell formed at conception; also called a fertilized egg.
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oConception…The union of the ovum and sperm cells.
oFallopian Tubes…Two hollow tubes that connect to the uterus and have fingerlike projections that reach toward each ovary.
oUterus...The organ in which the baby develops and is protected until birth.
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The Menstrual Cycle 8
Resourceshttp://www.webmd.com/baby/healthtool-ovulation-calculator
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“The average menstrual cycle is 28 to 32 days. Some women have longer or shorter cycles, so the exact timing of ovulation can vary. Here's an overview of a typical 28-day menstrual cycle”
Day 1
Your cycle begins on the first day of blood flow.
Days 2-14 Follicular Phase
The follicles on your ovary become active, and your cervical mucus starts to thin.
Day 14Ovulation occurs mid-cycle, but can vary from between Day 11 and Day 21 of a woman's cycle. Rising estrogen levels trigger the LH surge, which causes the follicle to ovulate and release an egg. It's important to chart your basal body temperature and LH surge so you know when you ovulate.
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o Days 15-22 Luteal Phaseo After releasing the egg, the
follicle produces progesterone, which thickens the lining of the uterus for implantation.
o Days 23 to 24o Implantation of a fertilized egg
can take place. At this point, hormones produced by pregnancy may be detected by a pregnancy test.
o Days 25 to 28o If pregnancy does not occur, your
hormone levels begin to fall. The uterine lining sheds, resulting in your period.
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There’s An App for That
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Genetic Fa
ctors a
nd
the U
nborn
Baby
o Genetic factors are the traits passed through the genes.
o They are the blueprint for the baby. “the plans”
o Inherited traits are passed to the baby at conception.
o The code “plan” is stored in DNA.
o The DNA is a chemical compound that is found in threadlike structures called chromosomes.
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Chromosomes & Genes
o Chromosomes: rod-shaped structures, located in the nucleus of a cell, that carry genetic information. Each cell contains 46 chromosomes.
o Genes: segments of a DNA molecule, located on a chromosome, that contain genetic information. Genes carry traits from parents to children.
Chro
moso
mes
oAll living things have a certain number of chromosomes.
oEach baby has 46=23MOM+23DAD
oMeaning…each sperm carries 23 chromosomes from dad, and the ovum carries 23 from mom.
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oSex Determination is decided at the moment you conceive. One pair of the baby’s chromosomes, determines it’s sex.
o These chromosomes are called “X” and “Y” chromosomes.
o Females: 2 “X” chromosomes
o Males: 1 “X” and 1 “Y” chromosomes
Eggs contain only “X” sex
chromosomes.
Sperm contain either “X” or “Y”
chromosomes.
The fathers contribution is the
one that determines the
sex of the fetus.
http://www.babycenter.com/2_inside-pregnancy-girl-or-boy_10313041.bc
Dominant & Recessive Traits
o In each chromosome, the genes occur in pairs.o One gene from mom, one from
dad
o The genes work together to determine the traits of the baby.
o Moms and dads can pass traits that do not show up in them.
o As a general rule…dominant traits ALWAYS show. 1 recessive trait will not usually show. 2 recessive traits usually show.
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oDominant Trait…Traits that always show in a person even if only one gene of the pair is inherited for that trait.
oRecessive Traits…Traits that typically do not show in a person unless both genes for the trait are inherited.
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Fun f
act
so Tallness is a dominant
trait, shortness is a recessive trait
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Multiple
Pregnancy
Mult
iple
Bir
ths
o Sometimes 2 or more babies develop in the same pregnancy.
o It’s called a multiple pregnancy.
o Become more common because of fertility medications
o The frequency of twins is about 1 in 35 births.
o Three or more is 1 in 540 births.
o The more babies…the higher the risks to the babies.
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Frate
rnal Tw
ins
vs Identica
l Twin
so FRATERNAL:
o There are 2 ova and 2 sperm=2 babies
o Different genetic makeup
o May or may not look alike, be the same gender
o Each has their own chorion (membrane in the uterus)
o IDENTICAL:
o There is a single ova and a single sperm that SPLITS.
o They do not know why this happens.
o If it does not completely split the twins will be conjoined.
o Identical twins look like but have different finger prints, footprints.
o The usually share the same chrion, but may have separate chrions.
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Stages of Development
http://www.youtube.com/watch?v=fKyljukBE70
Start at 2:00 end at 6
Germ
inal S
tage
1st S
tage
o Conception through 2 weeks
o The zygote remains a single cell for about 1 day
o On the 3rd day, there are 32 cells
o Cell divisions rapidly occurring
o The Fertilized egg travels to the uterus and floats about
o About 10 to 12 days after conception, the ball of cells embeds in the wall of the uterus
o The chorion, Amnion, placenta, and umbilical cord beginning to form
o This stage ends when the baby can receive nourishment from the mother
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Em
bry
onic
Sta
ge
o The second stage of development is 2 weeks through 8 weeks – baby is called an embryo
o Internal organs are developed – muy importante!
o Tissue segments in the spinal column are forming
o Limb buds appear
o Ears and eyes begin to form
o When this stage ends, they look like a human
o Feeding through umbilical cord
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Feta
l Sta
ge
oBegins about 9 weeks until birth, the baby is called a fetus
oBone starts to replace cartilage
oAll parts of the body mature
oHeartbeat can be heard
oMovement can be felt about 4-5 months
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Marshmallow Pyramid
o Students will work together in groups.
o Each group will design a freestanding pyramid.
o 3 minutes
o Items Needed
o 4 large bags of marshmallow
o toothpicks
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