Transcript Child Development

Child Development
Chapter 4: Prenatal Development
Journal
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Write down 5 phrases that explain what
you know about pregnancy.
State Standards
3.1 Analyze hereditary and environmental
factors affecting prenatal development
beginning with conception
 3.2 Analyze maternal and paternal health
and environmental factors affecting
conception and prenatal development
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Video
Brain Pop Reproductive System
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Conception
Vocabulary
•Ovum
•Uterus
•Fallopian Tube
•Sperm
•Conception
Family Planning
The only 100% method of contraception
is abstinence
 An ovum usually lives 12-24 hours
 A sperm usually lives 48-72 hours
 There are approximately 3-4 days in
which intercourse could lead to
conception
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Contraceptive Methods
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Groups 1-2
Each group will have 1 method.
Your responsibilities:
◦ Find a picture of an example of that method
◦ Turn picture into the assignment turn in folder
◦ Give a 30 second spill about that method and
show picture
Grade: Assignment worth 20 points
◦ 5 points for picture
◦ 10 points for spill
◦ 5 points for professionalism
Brainpop Video
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“Genetics”
Genetic Package
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Each person inherits characteristics from parents
Chromosomes: tiny threadlike particles in the nucleus
of every cell
◦ Human babies receive 46 at conception- 23 pairs
◦ Each chromosomes has thousands of genes: the units that
determine inherited characteristics
◦ For every inherited characteristic a person receives two copies
of a gene- mother and father
◦ Dominant Gene: stronger
◦ Recessive Gene: weaker
◦ Genome: The complete blueprint for the creation of a person
Making a Unique Person
Family often times look alike because of
the gene combinations
 Sex of a child is also determined at
conception
 Two types of sex chromosome: X and Y
 Egg cells contain X
 Sperm cells contain wither X or Y
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Brainpop Video
“Heredity”
 Punnett Square Activity
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Multiple Births
Identical Twins: Fertilized egg divides into two
separate babies
 Fraternal Twins: two eggs are released at the
same time and both are fertilized
 2.5% of births are multiple births
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◦ More than 2 babies is even more rare
◦ Most of the time multiple births (more than 2)
results from treatment of infertility: the inability to
become pregnant
Infertility
Not all people are able to become
pregnant
 1st step: Doctor evaluates both parent’s
help to determine cause
 Fertility drugs may be prescribed if the
cause is eggs are not released every
month
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◦ Several drawbacks: serious side effects,
multiple births, etc
Options for Infertility
After treatment for infertility some people are
still not able to conceive
 Some options:
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◦ Adoption
◦ Artificial Insemination: sperm injected into woman’s uterus
◦ In vitro Fertilization: Egg is fertilized outside body and then
placed in the woman’s uterus
◦ Ovum Transfer: egg from female donor then fertilized
◦ Surrogate Mother
Three Stages of Pregnancy
Prenatal Development: the baby’s
development during pregnancy
 Germinal Stage
 Embryonic Stage
 Fetal Stage
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Germinal Stage
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Zygote: The fertilized egg
Lasts only about 2 weeks
Cell Division
◦ Cell begins to grow while it is still in the
fallopian tube
◦ After about 4 days the zygote reaches the
uterus
Implantation
After about 2 weeks of growth the zygote is
about the size of a pin head
Embryonic Stage
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Embryo: developing baby from weeks 3-8
Organs and Body Systems:
◦ All the major system develop in this stage
◦ Brain begins to take control
◦ Brain is sensitive to damage from drugs and alcohol
Amniotic Sac
Amniotic Fluid
Placenta: Tissue that connects the developing baby to the
uterus
Umbilical Cord: long tube that connects the baby to the
placenta
Placenta and Umbilical cord are responsible for taking waste
away from and bringing nutrients to embryo
Fetal Stage
Fetus: developing baby during the fetal
stage
 Vocal chords develop
 Digestive system and kidneys begin to
function
 Movements are possible by the end of the
3rd month
 By 7th month fetus is capable of living
outside uterus but will require medical
intervention
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Fetal Stage, Continued
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Fetus can
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Suck thumb
Cough
Sneeze
Yawn
Kick
Hiccup
Cry
Preparing for Birth
Baby’s weight begins to shift down in 9th
month- “lightening”
 Fetus is turned upside down in mother’s
pelvis
 Less active
 Muscles of the uterus and abdomen can be
stretched up to 60 times their original size!
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◦ Return to original size in about 6 weeks after
pregnancy.
Assignment
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Complete Study Guide pages 33-36
Brainpop Video
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“Fetal Development”
Section 5-3
Problems in Prenatal Development
For Discussion
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Excerpt from Helen Keller’s The Story of
My Life
Objectives
Contrast miscarriage and stillbirth
 Identify some major birth defects
 Explain the four causes of birth defects
 Describe how birth defects can be
diagnosed and prevented
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Key Terms
Amniocentesis
 Birth Defect
 Chronic Villi Sampling
 Miscarriage
 Stillbirth
 Ultrasound
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Losing a Baby
Sometimes babies do not develop
normally
 In some cases the developing baby will die
 Before 20 weeks- miscarriage
 After 20 weeks- still birth
 Loss of an unborn child is devastating to
parents
 As many as 20 percent of al pregnancies
end in miscarriage
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Types of Birth Defects
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Birth defect- serious problems that threatens a child’s
health or ability to live
About 3 out of 100 children are born with a birth
defect
Birth defects affect:
◦ Shape or size of the body or of certain parts of the body
◦ A part or system of the body does not work properly
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Not all birth defects are apparent at birth
Causes of Birth Defects
Scientists still don’t understand the cause
of all birth defects
 There are 4 main causes
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Environmental Causes
During the first few weeks of conception all the
baby’s major systems develop
 Things that affect the development of the baby
include:
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Nutritional balance of the mother’s diet
Diseases or infections the mother has
Harmful substances the mother takes in
Some medicines
Exposure to outside hazards such as radiation
Hereditary Causes
Thousands of genes make up a genetic blueprinteach person has about 5-6 imperfect recessive
genes
 A single copy of this defective gene- no effect
 2 copies of this gene=birth defect or a dominant
defective gene=birth defect
 Some inherited conditions affect only one sex
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◦ Ex- Hemophilia (prevents blood from clotting) and color
blindness
Errors in Chromosomes
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Some birth defects are linked to a
problem with the baby’s chromosomes
◦ Ex- too many or too few chromosomes
The child does not inherit this condition
 Most common is down syndrome
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◦ 1 child in every 800 births has down
syndrome
◦ Risk is higher in mothers over 35
◦ Child has an extra chromosome 21
Interaction of Heredity and
Environment
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Sometimes birth defects result from
heredity and environment combined
◦ Ex- A baby may inherit the tendency for a
heart defect but only appears if some factorsuch as a drug or virus- affects the baby
during development
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Researchers think this is probably the
cause of cleft lip and spina bifida
Prevention and Diagnosis of Birth
Defects
Children with birth defects have difficulty
leading normal lives
 The rest of the family is affected too
 Responsible couples do everything
possible to minimize the possibility of
birth defects
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Genetic Counseling
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Some people seek genetic counseling
◦ May or may not already have a child with a birth defect
Does not tell people what to do, only explains
risks and options
 Family doctors can perform this service, but is
best provided by a specialist
 The genetic counselor first gathers family
histories from the couple
 Then they are given thorough medical
examinations and sometimes tests
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Prenatal Testing
More than 100 birth defects can now be found
before a baby is born
 There is not a test to tell if a child will be normal
 These tests can alert the physician of problems;
many times they can be taken care of before birth
or immediately following birth
 Sometimes blood testing can reveal birth defects
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Types of Prenatal Tests
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Ultrasound- checks for specific health problems
◦ Can show if the fetus is developing on schedule
◦ Can confirm due date
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Amniocentesis- Process of withdrawing a sample of amniotic fluid
and then testing it for indications of birth defects
◦ About 1 out of 200 amniocentesis tests result in miscarriage
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Chronic Villi Sampling- Tests a small amount of the tissue
surrounding the fetus
◦ Guided by a ultrasound image the doctor inserts a small tube throught
the woman’s vagina into the uterus; the samples are then obtained by
snipping or suction
◦ Risk of miscarriage or birth defect is mush higher than amniocentesis
Ask the Experts
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P. 163
Section 5-4
Avoiding Dangers to the Baby
Key Terms
Fetal Alcohol effects
 Fetal Alcohol Syndrome
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Objectives
Identify the hazards that alcohol and
other drugs pose to prenatal
development
 Discuss other environmental hazards that
pregnant women should avoid
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Alcohol
Alcohol is a drug
 Fetal Alcohol Syndrome- a pregnant woman
who drinks is at risk for her child developing
FAS
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Includes physical and mental problems
1 in 5 babies with FAS die soon after birth
Almost all are mentally retarded
Other problems: slow growth, poor coordination,
heart defects, and facial disfigurement
◦ Also, learning disabilities and hyperactivity
Alcohol, continued
Fetal Alcohol Effects- less severe than FAS, but
still suffers from some of the same problems
 Severity depends on amount consumed by
mother, stage of pregnancy, and presence of
other drugs in the mother’s system
 Can be prevented by not drinking!
 It is not know how much alcohol will cause
the syndrome
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Other Drugs
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Prescription and over the counter drugs
◦ No such thing as a completely safe drug
◦ First 3 months are most critical
◦ Last 6 months- slowed growth, infections, and
bleeding at birth
◦ Meds should not be taken unless approved by
the doctor
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Caffeine- also a drug, can cause birth
defects as well, not sure about amounts
Other Drugs, continued
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Tobacco- the more a mother smokes the smaller the
baby will be
◦ Heavy smoking can cause premature birth
◦ Linked to respiratory infections, allergies, and asthma
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Illegal Drugs- a mother who is addicted to an illegal
drug normally passes the addiction to the baby
◦ After birth the baby must go through withdrawal, some babies
die
◦ Long-term effects may be serious, many of these children have
problems following directions and learning disabilities
X Rays
Radiation can cause birth defects as well
 Pregnant women should warn medical
personnel
 Always request abdominal shields during
x rays
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Rubella
When a pregnant woman contracts
rubella babies can suffer with deafness,
blindness, heart disease, or mental
retardation
 Vaccines are available but can be
dangerous for women who are pregnant
or become pregnant shortly after the
shot
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Sexually Transmitted Diseases
Include: Syphilis, Gonorrhea, Hepatitis B,
Genital Herpes, AIDS, Group B
Streptococcus, Chlamydia
 Can be passed from mother to child
 Can result in death or other birth defects
 You can have a STD without knowing it!
 AIDS- the virus that causes AIDS can be
passed from mother to child
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