life span development. prenatal - development genetics in brief
TRANSCRIPT
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 blueprint…. Your genetic make-up
The Genetic Makeup of One Cell
Chromosomes
• Are the blueprint to you• Threadlike structures made up
of DNA – chemical basis of heredity
• 46 in each cell• 23 received from each parent
Chromosomes
Deoxyribonucleic Acid (DNA)
• A complex molecule
• Contains the genetic information of each chromosome
• Each gene has information like eye color, hair color, height, handedness
Dominant and Recessive
• Genotype—underlying genetic makeup
• Phenotype—traits that are expressed
• Dominant genes—will always be expressed if present
• Recessive genes—will not be expressed unless they are in a pair
Characteristic Dominant Recessive
Eye color Brown Grey, blue
Hair Dark Curly
Light Straight
Hands Extra fingers Limb dwarfing
5 fingers Normal limbs
Face Broad lips Dimples
Thin lips No dimples
Sex Linked Traits
• Traits linked to the X or Y (sex) chromosomes
• Usually recessive and carried on the X chromosome
• Appear more frequently in one sex than another
• Color blindness, baldness, hemophilia, Fragile X
Physical and Psychological Development Related
• Physical development begins at conception
• Physical maturity sets limits on psychological ability– visual system not fully functional at birth– language system not functional until much later
• Prenatal environment can have lifetime influence on health and intellectual ability
• http://www.youtube.com/watch?v=65BV5dXXxzM
• Video
Conception to BirthPrenatal Development
What are the three times in a woman’s life when she can’t get
pregnant?• Before puberty• After menopause• And when she is pregnant – (if she gets
pregnant with another –SHE IS STILL PREGNANT)
• ANY OTHER TIME – A WOMAN IS FERTILE
Prenatal Development
• Prenatal defined as “before birth”
• Prenatal stage begins at conception and ends with the birth of the child.
Prenatal Development• Conception—when a sperm penetrates the
ovum
• Zygote—a fertilized egg
• Germinal period—first two weeks after conception
• Embryonic period—weeks three through eight after conception
• Fetal period—two months after conception until birth
Prenatal Influences on Development
• Nutrition• Anxiety• Mother’s general health• Maternal age• Teratogens—any agent that causes
a birth defect (e.g., drugs, radiation, viruses)
• Ovulate
• 350 Million Sperm
• Uterus
Zygote• A newly fertilized egg
• The first two weeks are a period of rapid cell division.
• the cells start specialize in function
Zygote cont.
• After 10 days zygote attaches to the mother’s uterine wall – TRANSITIONS TO THE EMBRYO STAGE
• It stays there for approximately the next 37 weeks
5 Days old
Prenatal Development
Discussion
1. What exactly is conception?
2. What is a zygote?
3. How long does the zygote stage last?
Embryo
• 14 days until the end of the eight week
• Most of the major organs are formed during this time.
• Heartbeat, Red Blood Cells
Embryo – 45 Days
4 Weeks
Prenatal Development – 2 months
STOP WRITING
• Please stand up
• Jump 5 times
• Pick your own partner – a different person this time please
• Let’s discuss
Discussion
1. What is conception?
2. What is a zygote?
3. After the Zygote stage, what is the next stage?
4. What are the main characteristics of the embryonic stage
• Make it’s first movements
Fetal Period• The period
between the beginning of the ninth week until birth
From conception to the first year
•Fetal stage— the 9th week on
•Unmistakably human in form
• further development of organs and systems: marked increase in nervous system development and brain weight
9 Weeks
18 Weeks
24 Weeks
30 Weeks
35 Weeks
Time to Process!!!!!
Discussion
1. What is a zygote?
2. What are the characteristics of embryos?
3. What are fetuses?
• Umbilical Cord
• Video
• http://www.youtube.com/watch?v=kKMLfQ_EH7c&feature=related
• Problems that can occur–Harmful influences that can cross the placenta barrier
–Called teratogens-include German measles, radiation, toxic chemicals, sexually transmitted diseases, cigarette smoking, heavy alcohol consumption, prescription and nonprescription drugs.
Teratogens• Substances that pass through the
placenta’s screen and prevent the fetus from developing normally
• Includes: radiation, toxic chemicals, viruses, drugs, alcohol, nicotine, etc.
• STOP Drinking and taking drugs, even over-the-counter medication
These children were born addicted to cocaine
This child was left by her cocaine addicted mother
Fetal Alcohol Syndrome (FAS)
• A series of physical and cognitive abnormalities in children due to their mother drinking large amounts of alcohol during pregnancy
Smoking and Birth Weight
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.
The Beginnings of Life:
The Newborn
Infant Reflexes• Rooting—turning the head and
opening the mouth in the direction of a touch on the cheek
• Sucking—sucking rhythmically in response to oral stimulation
• Babinski—fanning and curling toes when foot is stroked
Infant Reflexes
• Moro—throwing the arms out, arching the back and bringing the arms together as if to hold onto something (in response to loud noise or sudden change in position of the head)
• Grasping—curling the fingers around an object
Temperament
• A person’s characteristic emotional reactivity and intensity
Temperament• A baby’s temperament is
apparent after just a few hours of birth
–“easy” babies – eat and sleep regularly
–“difficult” – unpredictable, intense, & irritable
• Newborns are able to see, but are nearsighted.
• -prefer faces over other stimuli in the environment.
• Prefer the sounds of their parent’s voices over others
Physical Development in Infancy and
Childhood
Infant, Toddler, Child
• Infant: First year
• Toddler: From about 1 year to 3 years of age
• Child: Span between toddler and teen
Neural Development
Maturation
• Biological growth processes that enable orderly changes in behavior
Motor Development
• Includes all physical skills and muscular coordination
• When did you first roll over, sit up, walk, ride a bike???
Motor Development
Social Development in Infancy and
Childhood
Stranger Anxiety
• The fear of strangers an infant displays around 8 months of age
• Lasts until approx. 2 1/2
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 adversely affect attachment, however, differences in normal child-rearing practices have no affect
• Daycare does not affect attachment
• Temperament, chronic stress, and rejection can affect attachment
• Cultural expectations can also play a role
Familiarity
• Sense of contentment with that which is already known
• Infants are familiar with their parents and caregivers.
Responsiveness
• Responsive parents are aware of what their children are doing.
• Unresponsive parents ignore their children--helping only when they want to.
Securely or Insecurely Attached
• Securely attached – children will explore their environment when primary caregiver is present
• Insecurely attached – children will appear distressed and cry when caregiver leaves. Will cling to them when they return
Harry Harlow• Did research with infant
monkeys on how body contact relates to attachment
• The monkeys had to chose between a cloth mother or a wire mother that provided food.
• The monkeys spent most of their time by the cloth mother.
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.