Growth and Development Chapter 24 Notes

  1. What is the prenatal period?
    Conception until birth
  2. Define embryology.
    Science of fetal growth and development.
  3. What is fertilization?
    Fusion of one sperm with the ovum, also called conception.
  4. Where does fertilization occur?
    Outer third oviduct (uterine or Fallopian tube)
  5. What is a zygote?
    Fertilized ovum, single-celled organism formed by union of one sperm with ovum; zygote is genetically complete
  6. After 3 days of cell division, the zygote has develops into a solid cell mass called a . . .
  7. What happens during ovulation?
    An ovum is released from the ovary and it begins its journey through the uterine tube.
  8. What does the morula develop into?
    A hollow called a blastocyst so that implantation may occur
  9. What does the blastocyst form?
    ˜the amniotic cavity and chorion of the placenta.
  10. What does the amniotic cavity become?
    a fluid-filled, protective amniotic sac.
  11. What does the chorion become?
    The placenta
  12. What connects the blood vessels of the chorion to the placenta?
    Chorionic villi
  13. When does the blastocyst implant itself into the uterine lining?
    10 days after ovulation
  14. How are nutrients obtained before the placenta is functional?
    Diffusion from uterine fluids
  15. What are the functions of the placenta?
    • anchors the developing fetus to the uterus
    • provides a “bridge” for the exchange of nutrients and waste products between mother and baby
    • functions as an excretory, respiratory, and endocrine organ.
  16. What is the placenta composed of?
    The maternal side is lacunae filled with maternal blood; a very thin layer of placental tissue separates maternal blood from fetal blood
  17. What type of substances can invade the layer of placental tissue that separates maternal blood from fetal blood?
    alcohol, rubella, etc.
  18. How long is the embryonic phase?
    From the third week after fertilization to to the end of week 8 of gestation.
  19. How long is the fetal phase?
    From week 8 to week 39 of gestation?
  20. How long is gestation?
    About 39 weeks
  21. How is histogenesisdifferent from organogenesis?
    Formation of tissues happens before tissues become organs.
  22. Explain the process of birth (parturition).
    • week 39, uterus becomes irritable 
    • fetus takes head-down position against the cervix
    • contractions begin then labor is initiated
    • amniotic sac (water) ruptures
    • cervix dilates
    • fetus moves through vagina to exterior
  23. How long does birth (parturition) last?
    Generally 6 to 25 hours
  24. What are the two powers of labor that move the fetus through the cervix?
    Uterine contractions and maternal pushing.
  25. Describe stage one of labor.
    ˜period from onset of uterine contractions until dilation of the cervix is complete
  26. Describe stage two of labor.
    period from the time of maximal cervical dilation until the baby exits through the vagina
  27. Describe stage three of labor.
    ˜process of expulsion of the placenta through the vagina
  28. Describe stage four of labor.
    the recovery period immediately following delivery of placenta
  29. What does the Apgar score assess?
    General condition of a newborn infant
  30. What is a Cesarean section (C-section)?
    ˜surgical delivery, usually through an incision in the abdomen and uterine wall (2 incisions req.)
  31. Discuss the differences between identical and fraternal twins.
    Identical twins develop from one ovum and one sperm. Fraternal twins develop from multiple ova and sperm.
  32. What is an ectopic pregnancy and how is it treated?
    • implantation outside the uterus (tubal pregnancy)
    • treated by surgical removal of products of pregnancy
  33. What is placenta previa and how is it treated?
    • growth of the placenta at or near cervical opening, often resulting in separation of the placenta from the uterine wall
    • treated by delivery of the fetus by C-section
  34. What is abruptio placentae and how is it treated?
    • separation of a normally placed placenta from the uterine wall; causes fetal death within minutes and mother can hemorrhage
    • treated by emergency C-section
  35. What is preeclampsia?
    • toxemia of pregnancy
    • hypertension, proteinuria and edema
    • may progress to eclampsia, a severe toxemia that may result in death
    • occurs in about 1 out of 20 pregnancies 
    • causes largely unknown
  36. What are some examples of teratogens?
    Radiation [like x-rays], chemicals [like alcohol or drugs], and infections [like herpes or cytomegalovirus]
  37. What is the difference between a miscarriage and a stillbirth?
    The difference is the length of gestation at which it occurs; miscarriage occurs before the twentieth week. After 20 weeks, delivery of a lifeless infant is termed a stillbirth.
  38. What causes acquired birth defects?
  39. What is puerperal fever?
    ˜caused by bacterial infection that may progress to septicemia and death; occurs in mothers after delivery (postpartum)
  40. What can affect lactation and thus infant lactation?
    anemia, malnutrition and other factors
  41. What is mastitis?
    inflammation or infection of the breast
  42. What are some causes of postpartum infection?
    Bacteria that infects the mother through contaminated hands or equipment
  43. If a woman develops mastitis, is breastfeeding contraindicated? Why or why not?
    It may be contraindicated if the milk is contaminated with pathogenic organisms
  44. What are the four most common divisions of the postnatal period?
    infancy, childhood, adolescence, adulthood
  45. What gradual changes in relative proportions occur in the head, trunk and limbs as individuals grow?
    The head becomes proportionately smaller, and the legs become proportionately longer and the trunk shorter
  46. How long is infancy?
    • Birth to about 18 months
    • First 4 weeks called neonatal period
  47. What is neonatology?
    medical and nursing specialty concerned with the diagnosis and treatment of disorders of the newborn
  48. What changes occur at birth?
    • cardiovascular - at birth newborn must immediately become totally self-supporting 
    • respiratory - deep and forceful first breath
  49. What developmental changes from birth to 18 months?
    • ˜Doubling of birth weight by 4 months and tripling by 1 year
    • ˜Fifty percent increase in body length by 12 months
    • ˜Development of normal spinal curvature by 15 months
    • ˜Ability to raise head by 3 months˜
    • Ability to crawl by 10 months˜
    • Ability to stand alone by 12 months˜
    • Ability to run by 18 months
  50. What is childhood classified as?
    • infancy to puberty 
    • ˜overall rate of growth remains rapid but decelerates˜
    • continuing development of motor and coordination skills˜
    • loss of deciduous or baby teeth and eruption of permanent teeth
  51. At what age do girls and boys usually hit puberty?
    girls—12 to 14 years; boys—14 to 16 years
  52. What is adolescence classified as?
    • average age range of adolescence is from 13 to 19 years
    • period of rapid growth resulting in sexual maturity 
    • appearance of secondary sex characteristics
    • growth spurts at about 10 and boys about 12
  53. What is adulthood classified as?
    • many body traits don’t become apparent until adulthood, such as normal balding patterns.
    • growth plates fully close in adult
    • adulthood is characterized by maintenance of existing body tissues
    • degeneration of body tissue begins in adulthood
  54. What is gerontology?
    the study of aging
  55. What is senescence?
    another term for older adulthood
  56. What is older adulthood classified as?
    • degenerative changes
    • every organ system of the body undergoes degenerative changes
    • number of oxygen free radicals increases as one ages, thus increasing the rate of cellular damage
    • culminates in death
  57. What is progeria?
    It is a genetic disease that causes rapid apparent aging. Cells do not reproduce quickly enough and children begin to look old quickly. Most people die of cardiovascular disease in their teens or twenties.
  58. What are some theories of aging that scientists have?
    • free radicals increase the rate of cellular damage over time
    • nutrition, injury, disease and other environmental facts affect aging process
    • cellular changes due to "aging" viruses found in all living cells
    • "Aging" genes cause preprogrammed aging
    • diminished capacity of cells to reproduce over time
  59. What are free radicals?
    highly reactive forms of oxygen that are normal by-products of cellular respiration in the mitochondria and other cell processes.
  60. How does aging affect the skeletal system?
    • Aging causes changes in the texture, calcification, and shape of bones
    • Bone spurs develop around joints
    • Bones become porous and fracture easily
    • Degenerative joint diseases, such as osteoarthritis, are common
  61. What is lipping?
    Older bones develop indistinct and shaggy-appearing margins with spurs. This can restrict mobility.
  62. What affects does aging have on the integumentary system?
    • ˜with age, skin “sags” and becomes thin, dry, and wrinkled (or inelastic)
    • ˜pigmentation problems are common
    • ˜frequent thinning or loss of hair occurs
  63. What else happens to the skin during the aging process?
    It becomes inelastic and that contributes to some of the other changes.
  64. What affects does aging have on the central nervous system?
    • ˜risk of dementia, or loss of memory, with aging
    • ˜other degenerative conditions affecting nervous system
    • ˜some risk of depression
  65. How can presbyopia be helped?
    Through the use of bifocals, or glasses with two lenses, to help people see up close
  66. What is presbyopia?
    age-related farsightedness
  67. What is a cataract?
    Loss of transparency of lens or cornea is common
  68. How does aging affect senses?
    ˜All sense organs show a gradual decline in performance with age
  69. What causes a decline in the ability to hear?
    Loss of hair cells in the organ of Corti results in decline in ability to hear certain frequencies.
  70. What is glaucoma?
    increase in pressure in the eyeball; often the cause of blindness in older adulthood
  71. What affects does aging have on the cardiovascular system?
    • ˜Degenerative heart and blood vessel disease is among the most common and serious effects of aging
    • ˜Fat deposits in blood vessels (atherosclerosis) decrease blood flow to the heart and may cause complete blockage of the coronary arteries˜
    • Hardening of arteries (arteriosclerosis) may result in rupture of blood vessels, especially in the brain (stroke)
    • ˜Hypertension, or high blood pressure, is common in older adulthood
  72. What is a stroke?
    A blockage or hemorrhage of an artery in the brain; cerebrovascular accident [CVA].
  73. What can hardening and blockage of the arteries lead to?
    a heart attack or myocardial infarction (MI)
  74. What affects does aging have on the respiratory system?
    • calcification of costal cartilages which leads to a barrel chest
    • wasting of respiratory muscles decreases respiratory efficiency 
    • respiratory membrane thickens; movement of oxygen from alveoli to blood is slowed
  75. What is barrel chest?
    Ribs become “fixed” to the sternum; rib cage remains in a more expanded position; respiratory efficiency decreases.
  76. What is the effect of conversion of muscle cells to connective tissue?
    it decreases the strength of the muscles associated with inspiration and expiration
  77. What affects does aging have on the urinary system?
    • ˜Nephron units decrease in number by 50% between ages 30 and 75˜
    • Blood flow to kidney, and therefore ability to form urine, decreases˜
    • Bladder problems, such as inability to void completely, are caused by muscle wasting in the bladder wall
    • Benign prostatic hypertrophy in the male contributes to difficulty starting the urinary stream and completely emptying the bladder, there is also decreased bladder capacity.
  78. What affects does aging have on the reproductive system?
    • ˜Changes in the sexual response
    • Men—erection is more difficult to achieve and maintain; urgency for sex may decline
    • Women—lubrication during intercourse may decrease
    • ˜Changes in fertility
    • Men—may continue to be fertile throughout later adult years
    • Women—experience menopause (cessation of reproductive cycling) between the ages of 45 and 60
  79. What are symptoms that women experience when going through menopause?
    hotflashs, sleep disturbances, dryness and thinning of the vaginal wall
  80. What treatments are used today to help with the symptoms of menopause?
    HRT is used in younger women when they first enter menopause. Medications that do not contain estrogen are now available to help with symptoms.
  81. What is menopause?
    • ˜Not a disease condition, but a natural period of change
    • ˜Decreased blood estrogen levels leads to symptoms like hot flashes, sleep disturbances, and dryness in the vagina
  82. What can HRT cause?
    ˜increased risk of some cancers, stroke, and blood clotting disorders
  83. Name the stages of reproductive cycle.
    • Sperm (male gamete) and ovum (female gamete) fuse during fertilization 
    • Zygote
    • Morula
    • Blastocyst
    • Embryo 
    • Fetus 
    • Neonate 
    • Infant
  84. What is implantation?
    Fertilized egg becomes blastocyst then attaches to uterus
  85. How does the placenta form?
    the blastocyst forms chorion that have yet to be differentiated and the chorion forms the placenta
Card Set
Growth and Development Chapter 24 Notes
Notecards on Dr. B's chapter 24.