Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Questions to PonderSlide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32Slide 33Slide 34Slide 35Slide 36Slide 37Slide 38Slide 39Slide 40Slide 41Slide 42Copyright © Allyn & Bacon 2006Prenatal Development And Birth3This multimedia product and its contents are protected under copyright law. The following are prohibited by law:• any public performance or display, including transmission of any image over a network;• preparation of any derivative work, including the extraction, in whole or part, of any images;• any rental, lease, or lending of the program.http://www.ablongman.com/bee4eCopyright © Allyn & Bacon 2006•The Process of Conception–Ovum–Sperm•The Journey of Sperm toward Ovum•Chromosomes–DNA–Genes–X and Y chromosomesConception and GeneticsCopyright © Allyn & Bacon 2006•Twins–Identical–Fraternal•Twins in genetic research•Increases in multiple birthsConception and GeneticsCopyright © Allyn & Bacon 2006•Genotype — the genetic blueprint•Phenotype — observable characteristics•Dominant–recessive pattern–Dominant genes always express their characteristics–Recessive genes come in pairs to express their characteristics Conception and GeneticsCopyright © Allyn & Bacon 2006Copyright © Allyn & Bacon 2006•Polygenic Inheritance–Many genes blend together to increase the genetic outcomes seen in the phenotypeConception and GeneticsCopyright © Allyn & Bacon 2006•Genomic Imprinting–Some genes are biochemically marked at the time ova and sperm develop•Mitochondrial Inheritance–Genes passed only from mother to child Conception and GeneticsCopyright © Allyn & Bacon 2006Multi-Factorial Inheritance–Individuals and environment•Differ in their reactivity•Two-way interplay•Ecological framework–People process their experiences•Active versus passive–People shape and select their experiencesConception and GeneticsCopyright © Allyn & Bacon 2006The Mother’s Experience–First Trimester•The zygote•The cervix•Prenatal care•Ectopic pregnancyPregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 2006The Mother’s Experience–Second Trimester•Fetus grows rapidly•Sex can be determined after week 13•Fetal movement felt between week 16 and 18•Prenatal care may detect gestational diabetesPregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 2006The Mother’s Experience–Third Trimester•Colostrum•Emotional connection between mother and baby•Hiccups and thumbsucking visible•Regular periods of activity and rest•ToxemiaPregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 20063 Stages of Prenatal Development–The Germinal Stage: The Zygote•From conception to implantation•Specialization of cells needed to support development - Blastocyst–Placenta–Umbilical cord–Yolk sac–AmnionPregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 20063 Stages of Prenatal Development–The Embryonic Stage•Forms the foundations of all body organs•Neural tube develops•All major organs and systems begin to develop•By week 7, the Y chromosome directs the development of the penis with the help of testosteronePregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 20063 Stages of Prenatal Development–The Fetal Stage•Growth from 1/4 ounce and 1 inch to 7 ½ pounds and 20 inches in length•Refinement of all organ systems•Surfactant•Vernix•Age of viability—week 24•EngagementPregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 2006Sex Differences– Males are:•More physically active•More vulnerable to prenatal problems –Females are: •More sensitive to external stimulation•More rapid skeletal developmentPregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 2006Prenatal Behavior– Fetal response occurs to sounds and vibrations – Fetuses can differentiate between familiar and novel stimuli– Prenatal learning can influence motor and cognitive development– Very active fetuses tend to be active children who can be labeled “hyperactive”Pregnancy and Prenatal DevelopmentCopyright © Allyn & Bacon 2006Genetic Disorders•Autosomal Disorders –Caused by recessive genes•Phenylketonuria (PKU)•Sickle-cell disease•Tay-Sachs disease–Caused by dominant genes•Huntington’s diseaseProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Questions to Ponder•You are told by a genetic counselor that you have 25% chance of passing on a deadly genetic trait to your child. Do you still have a child? What factors influence your choice?•How do we curtail the use of teratogens, such as smoking and alcohol use, by pregnant women?Copyright © Allyn & Bacon 2006Genetic Disorders•Sex–Linked Disorders–Red–green colorblindness–Hemophilia–Fragile-X syndrome–Caused by recessive gene on X chromosome–Boys suffer more often than girlsProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Copyright © Allyn & Bacon 2006Chromosomal Errors•Trisomies–Trisomy 21 — Down Syndrome•Mental retardation•Distinctive facial features•Physical abnormalities–Maternal age is a major factorProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Chromosomal Errors•Sex Chromosome Anomalies–XXY — Klinefelter’s syndrome–XO — Turner’s syndrome–XXX — girls with an extra X–XYY — boys with an extra YProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Teratogens–Substances that cause damage to an embryo–Each organ system is most vulnerable to harm when its development is most rapid (Figure 3.5).–The first 8 weeks are the most dangerous.Problems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Teratogens•Maternal Diseases–Rubella–HIV –Other sexually transmitted diseases•Syphilis•Genital herpes•Gonorrhea•CytomegalovirusProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Copyright © Allyn & Bacon 2006Teratogens•Drugs–Smoking–Drinking•Fetal Alcohol Syndrome–Marijuana and Heroin–CocaineProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Other Maternal Influences•Diet –Folic acid deficiencies–Malnutrition•Low birth weight•Brain stunting•Fetal deathProblems in Prenatal DevelopmentCopyright © Allyn & Bacon 2006Other Maternal