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LIFE SPAN DEVELOPMENT
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
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
OVULATION AND CONCEPTION
PRENATAL DEVELOPMENT When are the 3 times in a woman’s life
when she can NOT get pregnant?Before pubertyAfter menopauseWhen she is pregnantAny other time, she is fertile
Prenatal = before birth Prenatal stage = conception to birth of
the child
PRENATAL DEVELOPMENT3 stages of prenatal developmentZygote period – first 2 weeksEmbryonic period – 2 weeks to 8
weeksFetal 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 implantationTransitions to embryonic stage
It stays there for approximately the next 37 weeks
LET’S STOP FOR A DISCUSSION1. What is DNA and what does it do?2. What exactly is conception? 3. What is a zygote? 4. 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
18 WEEKS
24 WEEKS
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 DISCUSSION1. What happens in the embryonic stage? 2. How long is the fetal stage? What happens
here?3. 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
Umbilical Cord
http://www.youtube.com/watch?v=kKMLfQ_EH7c&feature=related
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
EFFECTS OF SMOKING
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
Are humans completely helpless at Birth?
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?
DEVELOPMENTPhysical, 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
ONE MORE DISCUSSION How can the child’s temperament impact
attachment? Caregiver’s responsiveness? Cultural expectations?
How can attachment impact social development?
