PSYC1001 Lecture 5: Developmental Psychology
12 Jun 2018
School
Department
Course
Professor
Stages of Prenatal Development
Genetic Sequences influenced by Environmental Factors
STAGES OF PRENATAL DEVELOPMENT
occurs between conception and birth
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Begins in fallopian tube when sperm penetrates egg and forms a zygote
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Takes about 266 days for the one-celled zygote to become a fetus of 200 billion cells
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Prenatal development:
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From conception through implantation
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14 days
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Germinal period:
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From 3rd week through 8th week
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Formation of major organs
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Embryonic period:
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From 9th week until birth (38 weeks)
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Organ systems function; organism grows
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Fetal period:
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Three periods:
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Zygote travels towards uterus
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Divides and forms blastocyst
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16 to 64 cells
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First 14 days
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GERMINAL PERIOD
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Blastocyst implants in the uterine wall
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Layers of cells differentiate to become different parts of the body
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3rd to 8th week
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EMBRYONIC PERIOD
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Fetus capable of responding to light
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Able to hear
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Sound level in the uterus is 75db
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Mother's voice and heartbeat best heard
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Limit of viability = 24 weeks
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6 months
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Third trimester!
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Fetus begins putting on weight in the form of fat just beneath the skin
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7 months
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Period of rapid growth and refinement of organ and brain systems
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Fetus more responsive
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Behaviour becomes increasingly regular and integrated
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Fetuses become viable between 22-28 weeks
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Summary: Last 7 months
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FETAL PERIOD
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GENETIC SEQUENCES INFLUENCED BY ENVIRONMENTAL FACTORS
Organ systems and the brain are particularly susceptible during periods of rapid development
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Timing
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Dose
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Duration
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Effects depend on:
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Teratogens = any disease, drug or other environmental agent that can harm a developing embryo or fetus
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E.g. of teratogens… smoking, alcohol, drugs, bacteria on raw fish, cheese, meat, soft serve ice cream (E.coli etc.),
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2C - Developmental Psychology
Thursday, March 8, 2018
8:59 PM
PSYCH 1001 Page 1
Document Summary
Begins in fallopian tube when sperm penetrates egg and forms a zygote. Takes about 266 days for the one-celled zygote to become a fetus of 200 billion cells. Layers of cells differentiate to become different parts of the body. Fetus begins putting on weight in the form of fat just beneath the skin. Period of rapid growth and refinement of organ and brain systems. Teratogens = any disease, drug or other environmental agent that can harm a developing embryo or fetus. Organ systems and the brain are particularly susceptible during periods of rapid development. E. g. of teratogens smoking, alcohol, drugs, bacteria on raw fish, cheese, meat, soft serve ice cream (e. coli etc. E. g. of teratogens smoking, alcohol, drugs, bacteria on raw fish, cheese, meat, soft serve ice cream (e. coli etc. poison, toxoplasmosis, cat litter, radiation, viruses, pollution and co2, heavy metals etc. Case study: half aussie women drink while pregnant.
