Published on

Published in: Technology, Health & Medicine
1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • Chap.02.Revised

    1. 1. <ul><li>“ This multimedia product and its contents are protected under copyright law. The following are prohibited by law: </li></ul><ul><ul><li>any public performance or display, including transmission of any image over a network; </li></ul></ul><ul><ul><li>preparation of any derivative work, including the extraction, in whole or part, pf any images; </li></ul></ul><ul><ul><li>any rental, lease, or lending of the program.” </li></ul></ul>
    2. 2. <ul><li>The Process of Conception </li></ul><ul><ul><li>Ovum </li></ul></ul><ul><ul><li>Sperm </li></ul></ul><ul><li>The Journey of Sperm toward Ovum </li></ul><ul><li>Chromosomes </li></ul><ul><ul><li>23 pairs </li></ul></ul><ul><ul><li>DNA </li></ul></ul><ul><ul><li>Genes </li></ul></ul><ul><ul><li>X and Y chromosomes </li></ul></ul><ul><li>Gametes (Ovum & Sperm) </li></ul><ul><ul><li>Meiosis </li></ul></ul><ul><ul><li>Only 23 chromosomes </li></ul></ul>Conception and Genetics
    3. 3. Figure 2.1
    4. 4. Conception and Genetics <ul><li>Homozygous pair </li></ul><ul><ul><li>When the two sets of instruction are the same at any given locus </li></ul></ul><ul><li>Heterozygous pair </li></ul><ul><ul><li>When the two sets of instruction are different at any given locus </li></ul></ul>
    5. 5. <ul><li>Polygenic Inheritance </li></ul><ul><ul><li>Many genes blend together to increase </li></ul></ul><ul><ul><li>the genetic outcomes seen in the phenotype </li></ul></ul><ul><li>Multifactorial Patterns </li></ul><ul><ul><li>Expression of traits that are influenced by both genes and environment </li></ul></ul><ul><li>Genomic Imprinting </li></ul><ul><ul><li>Some genes are biochemically marked at the time ova and sperm develop </li></ul></ul><ul><li>Mitochondrial Inheritance </li></ul><ul><ul><li>Genes passed only from mother to child </li></ul></ul>Conception and Genetics
    6. 6. <ul><li>Genotype – the genetic blueprint </li></ul><ul><li>Phenotype – observable characteristics </li></ul><ul><li>Dominant-recessive pattern </li></ul><ul><ul><li>Dominant genes always express their characteristics </li></ul></ul><ul><ul><li>Recessive genes come in pairs to express their characteristics </li></ul></ul>Conception and Genetics
    7. 7. Figure 2.2
    8. 8. Figure 2.3
    9. 9. <ul><li>Twins </li></ul><ul><ul><li>Identical </li></ul></ul><ul><ul><li>Fraternal </li></ul></ul><ul><li>Twins in genetic research </li></ul>Conception and Genetics
    10. 10. <ul><li>3 Stages of Prenatal Development </li></ul><ul><ul><li>The Germinal Stage – the zygote </li></ul></ul><ul><ul><ul><li>From conception to implantation </li></ul></ul></ul><ul><ul><ul><ul><li>Lasts from 10 days to 2 weeks </li></ul></ul></ul></ul><ul><ul><ul><li>Blastocyst divides into 2 sections </li></ul></ul></ul><ul><ul><ul><ul><li>Section that will become the baby </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Specialization of cells needed to support development – </li></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Placenta </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Umbilical cord </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Yolk sac </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Amnion </li></ul></ul></ul></ul></ul>Development from Conception to Birth
    11. 11. Figure 2. 4
    12. 12. <ul><li>3 Stages of Prenatal Development </li></ul><ul><ul><li>The Embryonic Stage </li></ul></ul><ul><ul><ul><li>Forms the foundations of all body organs </li></ul></ul></ul><ul><ul><ul><li>Neural tube develops </li></ul></ul></ul><ul><ul><ul><li>All major organs and systems begin to develop </li></ul></ul></ul><ul><ul><ul><li>By week 7, the Y chromosome directs the development of the penis with the help of testosterone </li></ul></ul></ul>Development from Conception to Birth
    13. 13. <ul><li>3 Stages of Prenatal Development </li></ul><ul><ul><li>The Fetal Stage </li></ul></ul><ul><ul><ul><li>Growth from 1/4 th ounce and 1 inch to </li></ul></ul></ul><ul><ul><ul><li>7 ½ pounds and 20 inches in length </li></ul></ul></ul><ul><ul><ul><li>Refinement of all organ systems </li></ul></ul></ul><ul><ul><ul><li>Surfactant </li></ul></ul></ul><ul><ul><ul><li>Vernix </li></ul></ul></ul><ul><ul><ul><li>Age of viability - week 24 </li></ul></ul></ul><ul><ul><ul><li>Engagement </li></ul></ul></ul>Development from Conception to Birth
    14. 14. <ul><li>Nervous System </li></ul><ul><ul><li>Neural tube develops at week 4 </li></ul></ul><ul><ul><li>Glial Cells </li></ul></ul><ul><ul><ul><li>Provides the glue that holds the nervous system together </li></ul></ul></ul><ul><ul><ul><li>Helps remove debris after neuronal death </li></ul></ul></ul><ul><ul><ul><li>Segregates neurons from each other </li></ul></ul></ul><ul><ul><li>The Fetal Stage Continued </li></ul></ul>
    15. 15. Figure 2.5
    16. 16. <ul><li>Nervous System </li></ul><ul><ul><li>Neurons </li></ul></ul><ul><ul><ul><li>Dendrites </li></ul></ul></ul><ul><ul><ul><ul><li>Major receptors of nerve impulses </li></ul></ul></ul></ul><ul><ul><ul><li>Axons </li></ul></ul></ul><ul><ul><ul><ul><li>Primary transmitting apparatus </li></ul></ul></ul></ul><ul><ul><ul><li>Synapses </li></ul></ul></ul><ul><ul><ul><ul><li>Fluid-filled gap between neurons </li></ul></ul></ul></ul><ul><ul><ul><ul><li>allow neurotransmitters to pass between neurons </li></ul></ul></ul></ul><ul><ul><li>Most neurons are born between 10 and 18 weeks </li></ul></ul><ul><ul><li>The Fetal Stage Continued </li></ul></ul>
    17. 17. Figure 2.6
    18. 18. Sex Differences in Prenatal Development <ul><li>Between week 4 and 10, males begin to secrete testosterone from primitive testes </li></ul><ul><ul><ul><li>Necessary to develop male genitalia </li></ul></ul></ul><ul><ul><ul><li>Lack of testosterone will “demasculinize” the male embryo </li></ul></ul></ul><ul><ul><ul><li>Too much testosterone will defeminize the female embryo </li></ul></ul></ul><ul><li>Prenatal hormones may influence sex differences in: </li></ul><ul><ul><li>Brain development </li></ul></ul><ul><ul><li>Hormones in adolescence </li></ul></ul><ul><ul><li>Levels of physical aggression </li></ul></ul><ul><ul><li>Relative dominance of right and left hemispheres </li></ul></ul>
    19. 19. Sex Differences in Prenatal Development <ul><li>Girls </li></ul><ul><ul><li>Slightly faster skeletal development </li></ul></ul><ul><li>Boys </li></ul><ul><ul><li>Slightly heavier and longer at birth </li></ul></ul><ul><ul><li>More vulnerable to prenatal problems </li></ul></ul><ul><ul><li>More likely to be aborted spontaneously </li></ul></ul><ul><ul><li>Have more birth injuries and birth defects </li></ul></ul><ul><ul><li>X-related problems may be a factor </li></ul></ul><ul><ul><li>Slightly more active before birth </li></ul></ul>
    20. 20. Prenatal Behavior <ul><li>Fetuses respond to sound with body movements as early as 25 weeks </li></ul><ul><li>Can distinguish between familiar and novel stimuli by 32 weeks </li></ul><ul><li>Learning may begin prenatally </li></ul><ul><ul><li>“ The Cat in the Hat” experiment </li></ul></ul><ul><li>Music played prenatally may lead to advanced motor and cognitive skills at six months </li></ul>
    21. 21. Questions to Ponder? <ul><li>How would you deal with a risk of passing on a severe genetic illness to any child that you and your partner might have? </li></ul><ul><li>If you are having a baby, would you add music and reading to your child prenatally to your pregnancy routine? Why or why not? </li></ul>
    22. 22. <ul><li>Genetic Disorders </li></ul><ul><li>Autosomal Disorders </li></ul><ul><ul><li>Caused by recessive genes </li></ul></ul><ul><ul><ul><li>Phenylketonuria (PKU) </li></ul></ul></ul><ul><ul><ul><li>Sickle-cell disease </li></ul></ul></ul><ul><ul><ul><li>Tay-Sachs disease </li></ul></ul></ul><ul><ul><li>Caused by dominant genes </li></ul></ul><ul><ul><ul><li>Huntington’s disease </li></ul></ul></ul><ul><ul><ul><li>Schizophrenia </li></ul></ul></ul><ul><ul><ul><li>Migraine headaches </li></ul></ul></ul><ul><ul><ul><li>Extra fingers </li></ul></ul></ul>Problems in Prenatal Development
    23. 23. <ul><li>Genetic Disorders </li></ul><ul><li>Sex-linked Disorders </li></ul><ul><ul><li>Red-green colorblindness </li></ul></ul><ul><ul><li>Hemophilia </li></ul></ul><ul><ul><li>Fragile-X syndrome </li></ul></ul><ul><ul><li>Caused by recessive gene on X chromosome </li></ul></ul><ul><ul><li>Boys suffer more often than girls </li></ul></ul>Problems in Prenatal Development
    24. 24. Figure 2.7 – Sex Linked Transmission of a Recessive Disease
    25. 25. <ul><li>Chromosomal Errors </li></ul><ul><li>Trisomies </li></ul><ul><ul><li>Trisomy 21 – Down Syndrome </li></ul></ul><ul><ul><ul><li>Mental retardation </li></ul></ul></ul><ul><ul><ul><li>Distinctive facial features </li></ul></ul></ul><ul><ul><ul><li>Physical abnormalities </li></ul></ul></ul><ul><ul><li>Maternal age is a major factor </li></ul></ul>Problems in Prenatal Development
    26. 26. <ul><li>Chromosomal Errors </li></ul><ul><li>Sex Chromosome Anomalies </li></ul><ul><ul><li>XXY – Klinefelter’s syndrome </li></ul></ul><ul><ul><li>XO – Turner’s syndrome </li></ul></ul><ul><ul><li>XXX – girls with an extra X </li></ul></ul><ul><ul><li>XYY – boys with an extra Y </li></ul></ul>Problems in Prenatal Development
    27. 27. <ul><li>Teratogens: Maternal Diseases </li></ul><ul><li>Rubella </li></ul><ul><ul><li>Vaccinations should be given to all children </li></ul></ul><ul><li>HIV </li></ul><ul><li>Other sexually transmitted diseases </li></ul><ul><ul><li>Syphilis </li></ul></ul><ul><ul><li>Genital herpes </li></ul></ul><ul><ul><li>Gonorrhea </li></ul></ul><ul><ul><li>Cytomegalovirus </li></ul></ul>Problems in Prenatal Development
    28. 28. Figure 2.8
    29. 29. <ul><li>Other Maternal Influences </li></ul><ul><li>Chronic Illnesses </li></ul><ul><ul><li>Heart disease, diabetes, lupus, hormone imbalances can all lead to developmental delays </li></ul></ul><ul><li>Fetal-maternal medicine helps to manage the effects of long-term illnesses </li></ul>Problems in Prenatal Development
    30. 30. <ul><li>Environmental Hazards </li></ul><ul><li>Limiting exposure to mercury </li></ul><ul><li>Avoiding possible harmful chemicals </li></ul><ul><ul><li>Lead </li></ul></ul><ul><ul><li>Arsenic </li></ul></ul><ul><ul><li>Anesthetic gasses </li></ul></ul><ul><ul><li>Solvents </li></ul></ul><ul><ul><li>Parasite-bearing substances </li></ul></ul>Problems in Prenatal Development
    31. 31. <ul><li>Teratogens: </li></ul><ul><ul><li>Substances that cause damage to an embryo </li></ul></ul><ul><ul><li>Each organ system is most vulnerable to harm when its development is most rapid </li></ul></ul><ul><ul><li>(Figure 2.8) </li></ul></ul><ul><ul><li>The first 8 weeks are the most dangerous </li></ul></ul>Problems in Prenatal Development
    32. 32. <ul><li>Teratogens: Drugs </li></ul><ul><li>Smoking </li></ul><ul><li>Drinking </li></ul><ul><ul><li>Fetal Alcohol Syndrome </li></ul></ul><ul><li>Cocaine </li></ul><ul><li>Marijuana and Heroin </li></ul>Problems in Prenatal Development
    33. 33. <ul><li>Other Teratogens and Maternal Factors </li></ul><ul><li>Vitamin A – large doses may cause malformations of head, face, heart </li></ul><ul><li>Aspirin </li></ul><ul><li>Lead – may lead to lower IQ </li></ul><ul><ul><li>3–6% infants and young children have high levels of lead </li></ul></ul><ul><ul><li>Most are black or Hispanic children in inner cities </li></ul></ul>Problems in Prenatal Development
    34. 34. <ul><li>Other Maternal Influences </li></ul><ul><li>Diet </li></ul><ul><ul><li>Both general adequacy and the presence of certain key nutrients are essential in a pregnant woman’s diet </li></ul></ul><ul><ul><ul><li>Subnutrition – a diet that is barely adequate and lacking in some essential nutrients </li></ul></ul></ul><ul><ul><ul><li>Folic acid deficiencies – risk in neural tube defects </li></ul></ul></ul><ul><ul><li>Malnutrition (Especially before 3 months prenatally) </li></ul></ul><ul><ul><ul><li>Low birth weight </li></ul></ul></ul><ul><ul><ul><li>Brain stunting </li></ul></ul></ul><ul><ul><ul><li>Fetal death </li></ul></ul></ul><ul><ul><li>A woman’s caloric needs go up 10-20% during pregnancy </li></ul></ul>Problems in Prenatal Development
    35. 35. <ul><li>Other Maternal Influences </li></ul><ul><li>Age </li></ul><ul><ul><li>First pregnancies occurring later – 25.1 years </li></ul></ul><ul><ul><li>Women over 35 have higher risks for pregnancy complications </li></ul></ul><ul><ul><li>Teenage mothers </li></ul></ul><ul><ul><ul><li>May suffer from poverty and poor prenatal care </li></ul></ul></ul><ul><ul><ul><li>Children may exhibit learning and behavior problems in school </li></ul></ul></ul><ul><ul><ul><li>Both preterm and low birth weight babies were twice as common in preteen mothers </li></ul></ul></ul>Problems in Prenatal Development
    36. 36. <ul><li>Maternal Emotions </li></ul><ul><li>Stress </li></ul><ul><ul><li>Can change hormone levels </li></ul></ul><ul><li>Stressful life events, emotional distress, and physical stress are linked to slight increases in problem pregnancies </li></ul><ul><li>Severely distressed mothers produce infants who grow slowly </li></ul><ul><li>Social support and counseling may help </li></ul>Problems in Prenatal Development
    37. 37. Problems in Prenatal Development <ul><li>Poverty </li></ul><ul><ul><li>Low birth weight or stillborn babies are more common in poor mothers </li></ul></ul><ul><ul><li>More likely to have earlier pregnancies </li></ul></ul><ul><ul><li>Good prenatal care may help overcome difficulties </li></ul></ul>
    38. 38. End Show 2 <ul><li>“ This multimedia product and its contents are protected under copyright law. The following are prohibited by law: </li></ul><ul><ul><li>any public performance or display, including transmission of any image over a network; </li></ul></ul><ul><ul><li>preparation of any derivative work, including the extraction, in whole or part, pf any images; </li></ul></ul><ul><ul><li>any rental, lease, or lending of the program.” </li></ul></ul>