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Life Span Development. Prenatal Development. Genetics . (In Brief). Very Beginning . At conception, you were a cell no bigger than a period. In this cell contained your genetic make-up Chromosomes are the blueprint Threadlike structures made up of DNA – chemical basis of heredity
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Genetics (In Brief)
Very Beginning • At conception, you were a cell no bigger than a period. • In this cell contained your genetic make-up • Chromosomes are the blueprint • Threadlike structures made up of DNA – chemical basis of heredity • 46 in each cell • 23 received from each parent • XX for girls • XY for boys
Deoxyribonucleic Acid (DNA) • A complex molecule • Contains the information of each chromosome • Each gene has information like eye color, hair color, height, handedness • Like a recipe • Double helix (all the way) • What does this mean?!?!
Prenatal Development Conception to Birth
Prenatal Development • When are the 3 times in a woman’s life when she can NOT get pregnant? • Before puberty • After menopause • When she is pregnant • Any other time, she is fertile • Prenatal = before birth • Prenatal stage = conception to birth of the child
Prenatal Development • 3 stages of prenatal development • Zygote period – first 2 weeks • Embryonic period – 2 weeks to 8 weeks • Fetal period – 8 weeks to birth
Zygote Stage • A newly fertilized egg • Period of rapid cell division • Cells start specialize in function
Zygote Stage – Embryonic Stage • After 10 days, zygote attaches to the mother’s uterine wall • This is called implantation • Transitions to embryonic stage • It stays there for approximately the next 37 weeks
Let’s Stop for a Discussion • What is DNA and what does it do? • What exactly is conception? • What is a zygote? • How long does the zygote stage last?
Embryonic Stage • 14 days until the end of the 8th week • Most of the major organs are formed during this time • Heartbeat, red blood cells, brain divides into five vesicles
Fetal Stage • From the 9th week on • Unmistakably human in form • Further development of organs and systems • Marked increase in nervous system development and brain weight • At 12 weeks we can tell the sex
Fetal Stage • By mid-pregnancy a fetus has developed all five senses • The baby can hear, swallow, sleep, and move around • Music • During the 3rd trimester, the baby’s learning shifts from generalization to differentiation
Let’s Stop for a Discussion • What happens in the embryonic stage? • How long is the fetal stage? What happens here? • A mother delivers nutrients and oxygen to the fetus through the umbilical cord. If the mother is not careful, how can this be harmful to the baby?
The Beginnings of Life The Newborn
Video • http://www.youtube.com/watch?v=kKMLfQ_EH7c&feature=related
Problems that Can Occur • Harmful influences that can cross the placenta barrier through the umbilical cord • Teratogens prevent the fetus from developing normally • Include radiation, toxic chemicals, viruses, caffeine, drugs, alcohol, nicotine, etc. • Can be delivered directly to the fetus, alter the placenta, or cause harmful contractions • During which of the 3 stages of prenatal development are babies most susceptible to the effects of teratogens?
Fetal Alcohol Syndrome (FAS) • Alcohol is the leading known preventable cause of mental and physical birth defects in the US • Lifelong effects - mental retardation, poor growth, facial defects, and behavioral problems
Effects of Smoking • 4,000+ chemicals, especially nicotine and carbon monoxide • Stillbirth, premature delivery, and low birth weight • Impaired brain function: learning disorders, behavioral problems, and relatively low IQs
Drug Use During Pregnancy • Can result in miscarriage, low birth-weight, premature labor, placental abruption, fetal death, and even maternal death • Currently there is only one state, South Carolina, that holds prenatal substance abuse as a criminal act of child abuse and neglect
STOP Drinking and taking drugs, even over-the-counter medication
From conception to the first year • Newborns are able to see, but are nearsighted • 20/500 legally blind. • -prefer faces over other stimuli in the environment.
Birth to 1 Year • Are humans completely helpless at birth? • Newborns are able to see, but are nearsighted • 20/500 legally blind • Prefer faces over other stimuli in the environment • Prefer the sounds of their parent’s voices over others
Reflexes in the Newborn • Automatic, unlearned responses • Rooting • Sucking & Swallowing • Grasping • Stepping • Others • What is the purpose of these reflexes?
Temperament • A person’s characteristic emotional reactivity and intensity • A baby’s temperament is apparent after just a few hours of birth • “easy” babies – eat and sleep regularly • “difficult” – unpredictable, intense, & irritable
Let’s Stop for a Discussion • How can the mother’s choices during pregnancy affect the baby for life? • Why do you think babies prefer faces over other stimuli and their parents’ voices over other sounds? • How can a baby’s temperament influence his/her development?
Development Physical, Motor, Social
Physical Development • Infant: first year • Toddler: from about 1 year to 3 years of age • Child: span between toddler and teen • Maturation: biological growth processes that enable orderly changes in behavior
Motor Development • Includes all physical skills and muscular coordination
Social Development • Attachment: An emotional tie with another person resulting in seeking closeness • Children develop strong attachments to their parents and caregivers • Body contact, familiarity, and responsiveness all contribute to attachment • Factors affecting attachment: • Neglect, abuse, and deprivation • Temperament • Cultural expectations • NOT differences in normal child-rearing practices
Social Development • Attachment theory:John Bowlby (1958), a child needs to form an attachment with a caregiver to have a healthy social and emotional development • Imprinting: a process by which certain animals, early in life, form attachments • Konrad Lorenz • Critical period: an optimal period when the organism’s exposure to certain stimuli produce the imprinted behavior • Harry Harlow – 1957-1963 surrogate mother experiment with rhesus monkeys
http://www.youtube.com/watch?v=fLrBrk9DXVk&feature=related What does this reveal about a child’s needs?
Social Development • Quality of attachment affects child’s social development • Securely attached: children will explore their environment when primary caregiver is present • Insecurely attached: can compromise exploration, self-confidence and mastery of the environment • Stanger anxiety: the fear of strangers an infant displays around 8 months until 2 ½ years • Mary Ainsworth – 1970’s experiment called “The Strange Situation”
http://www.youtube.com/watch?v=36GI_1PBQpM&feature=related Secure or insecure attachment?
Social Development • Effects of attachment: • Secure attachment predicts social competence • Deprivation of attachment is linked to negative outcome • A responsive environment helps most infants recover from attachment disruption