Chapter 4 Prenatal Development Child Development Chapter 4 Prenatal Development

Section 1 The Developing Baby Chapter 4 Section 1 The Developing Baby

1. Explain the process of conception using the following terms: Fallopian tube, uterus, sperm, ovum. An ovum is released from the ovary. It travels through the Fallopian tube to the uterus. Conception occurs if sperm reach the Fallopian tube and penetrate and fertilize the ovum.

2. Prenatal Development Stage Time Span Development Germinal Conception to 2 weeks Zygote forms/grows by cell division; zygote implants in uterus Embryonic 3rd thru 8th week Embryo develops rapidly; major body systems form; brain begins to control body systems. Fetal 8th or 9th week thru birth Teeth/vocal cord buds develop; digestive/kidney system develops; movement begins; major organs become ready to function; gains weight

3. Explain each of the following: Amniotic fluid Liquid that fills the sac that forms around the developing baby to protect it.

Placenta Tissue rich in blood vessels that forms in the uterus Absorbs oxygen and nourishment from mother to pass to baby.

Umbilical cord Tube that carries nourishment and oxygen from the placenta to the baby

4. Changes in mother during first 2 months of pregnancy Menstrual period stops Breasts swell Frequent urination Possible nausea Fatigue (tiredness)

5. What is lightening and when does it occur? Baby shifts downward into the birth canal. It occurs near the end of the 40 weeks of pregnancy.

Inside Out: The Growing Years: Conception to Childhood – 28 minutes stop at 19:15?

Section 2 A Closer Look at Conception Chapter 4 Section 2 A Closer Look at Conception

6. What is heredity? Name 3 characteristics that can be hereditary. Heredity – the passing of characteristics from parents to children through genes. Hair color Eye color Blood type

7. Summarize the relationship between chromosomes, genes, genomes, and DNA. DNA – a complex molecule that makes up genes Genes – the units that determine a person’s inherited characteristics Chromosomes – tiny threadlike structures that are made up of hundreds or thousands of genes Genome – the complete genetic blueprint for the creation of a person

8. Explain the difference between dominant and recessive genes. The stronger of the pair of genes The characteristic it determines will be expressed when it is paired with a recessive gene Recessive the weaker of the pair of genes The characteristic it determines will only be expressed IF the person has a second recessive gene for that characteristic

9. Which parent can provide either an X or a Y to the baby 9. Which parent can provide either an X or a Y to the baby? Which chromosome must come from this parent for the child to be female? The father The X chromosome

10. Explain how each of the following occurs: Identical twins Fertilized egg develops into cell mass Cell mass splits in two Each part develops into separate embryo Fraternal twins Two separate eggs are fertilized by two separate sperm Two embryos form

11. What is the ONLY guaranteed way to avoid pregnancy? ABSTINENCE!!!!

A couple of definitions… Infertility – the inability to become pregnant Can occur in both men and women Surrogate – a substitute mother who becomes pregnant to have a baby for another woman

12. Complete the following chart about options for infertility. Description Adoption A child who is not biologically the couple’s child becomes a part of the family. Artificial insemination Sperm is injected into a woman’s uterus. In vitro fertilization An egg from the woman is removed and fertilized with sperm from the man and then placed in the woman’s uterus. Ovum transfer A fertilized egg from a donor is placed in the woman’s uterus. Surrogate mother A woman become pregnant for a woman who cannot have a baby.

13. What are 3 reasons a couple who want children might not use these options? Personal beliefs No specialists nearby Too expensive

Section 3 Problems in Prenatal Development Chapter 4 Section 3 Problems in Prenatal Development

14. Miscarriage – loss of a baby prior to 20th week Stillbirth – death of a baby after the 20th week of pregnancy

15. Birth Defects PKU – inability of body to process a certain protein Sickle cell anemia - malformed red blood cells interfere with oxygen supply Tay-Sachs disease – Lack of a certain blood chemical makes body unable to process certain fats in brain and nerve cells. Down Syndrome – extra chromosome 21 typically results in mental retardation

16. Causes of birth defects Environment- poor nutrition, diseases, harmful substances, medicines, exposure to hazards Heredity – inheriting 2 defective recessive genes, inheriting one defective dominant gene Errors in chromosomes – having too few or too many, broken, or rearranged Interaction of heredity and environment – inherited genetic predisposition toward a defect along with exposure to a hazard during pregnancy

17. What does a genetic counselor do? Uses info from physical exams and medical history to assess a couple’s risk for having a child with certain birth defects.

18. Prenatal tests Test Description Risk Alpha-fetaprotein Mom’s blood is tested for abnormal levels of protein No known risk Ultrasound Sound waves used to make video image Amniocentesis A small amount of amniotic fluid is removed and tested Some risk to fetus Chorionic villi sampling Tissue taken from membrane that encases fetus Moderate risk

Amniocentesis & Chorionic Villi sampling

Section 4 Avoiding Dangers to the Baby Chapter 4 Section 4 Avoiding Dangers to the Baby

19. Compare the fetal alcohol syndrome (FAS) and fetal alcohol effects? Similarities Both caused by consumption of alcohol during pregnancy Both cause many of same problems 1 in 5 FAS babies does not live to see 1st birthday Differences FAS is more severe

Fetal Abuse: The Effects of Drugs and Alcohol 17 mins

Learning Disabilities Caused by FAS 3 mins.

20. Why is it critical to avoid taking medications in the first 3 months of pregnancy unless specifically prescribed? The baby’s body systems, including the brain, are forming. Chemicals in some medications taken at this time may cause severe harm, including mental retardation.

21. Describe the possible effects on a baby of each hazard listed below. Caffeine Miscarriage Premature birth/Low birth weight Infant death Tobacco Low birth weight/Premature birth Respiratory infections allergies Cocaine Stroke Heart attack Seizures, SIDS, tremors Sleep and feeding difficulties Developmental delay

22. What is SIDS? The sudden death of a baby under one year of age with no clear cause.

SIDS 17 mins.

23. If an expectant mother needs X-rays because of an accident, why should she tell doctors that she is pregnant? X-rays can harm the baby. Doctors can take precautions to limit the baby’s exposure.

24. Give 3 examples of hazardous substances pregnant women should avoid. Paint Pesticides Lead Carbon monoxide Mercury Solvents Paint thinner

25. Infections during pregnancy Possible effects on baby Prevention Rubella Blindness, deafness, heart disease, mental retardation vaccine Toxoplasmosis Blindness, hearing loss, learning disabilities, death, mental disabilities, miscarriage, stillbirth Do not clean cat’s litter boxes; don’t eat undercooked meat; wash hands thoroughly after touching raw meat Chicken pox Skin scarring, limb defects, eye problems Get vaccine before pregnant STDs Serious illnesses; physical disabilities; death Get tested and treated AIDS 35-65% chance virus will pass from mom to baby; Attacks the brain; seizures, retarded, mental development Get tested