1. LIFE-SPAN DEVELOPMENT2
A Topical Approach to
LIFE-SPAN DEVELOPMENT
Biological Beginnings
John W. Santrock

2. The Evolutionary Perspective
Natural Selection and Adaptive Behavior
Evolutionary psychology—emphasizes importance of adaptation, reproduction, and “survival of the fittest” in shaping behavior

3. Evolutionary Developmental Psychology
The Evolutionary Perspective
Evolutionary Developmental Psychology
Extended “juvenile” period
Aspects of childhood as preparations for adulthood
Some characteristics of childhood adaptive
Evolved psychological mechanisms

4. Evaluating Evolutionary Psychology
The Evolutionary Perspective
Evaluating Evolutionary Psychology
Remains just one theoretical approach
Evolution does not dictate behavior
Biology allows broad range of cultural possibilities

5. DNA: The Collaborative Gene
Genetic Foundations
DNA: The Collaborative Gene
DNA—complex molecule that contains genetic information
Genes—units of hereditary information composed of DNA
Chromosomes—threadlike structures that contain sequences of genes

6. Cells, Chromosomes, Genes, and DNA
Genetic Foundations
Cells, Chromosomes, Genes, and DNA

7. Mitosis, Meiosis, and Fertilization
Genetic Foundations
Mitosis, Meiosis, and Fertilization
Mitosis
Cellular reproduction in which cell’s nucleus duplicates itself with two new cells
Meiosis
Specialized form of cell division that occurs to form eggs and sperm (gametes)
Reproduction
Process that, in humans, begins when a female gamete (ovum) is fertilized by a male gamete (sperm)
Zygote
Single cell formed through fertilization

8. Genotypes and Phenotypes
Genetic Foundations
Genotypes and Phenotypes
Genotype
Person’s genetic heritage; actual genetic material
Phenotype
Way an individual’s genotype is expressed in observed and measurable characteristics

9. Genetic Principles Dominant-Recessive Genes Principle Sex-Linked Genes
Genetic Foundations
Genetic Principles
Dominant-Recessive Genes Principle
Sex-Linked Genes
Genetic Imprinting
Polygenetic Inheritance

10. How Brown-Eyed Parents Can Have a Blue-Eyed Child
Genetic Foundations
How Brown-Eyed Parents Can Have a Blue-Eyed Child

11. Responsiveness of Genotypes to Environmental Influences
Genetic Foundations
Responsiveness of Genotypes to Environmental Influences

12. Genetic Foundations
Reaction Range
Range of possible phenotypes for each genotype, suggesting importance of environment’s restrictiveness or richness
Canalization—process by which characteristics take a narrow path or developmental course

13. Chromosome and Gene-Linked Abnormalities
Genetic Foundations
Chromosome and Gene-Linked Abnormalities
Down Syndrome—chromosomally transmitted form of mental retardation
Caused by extra (47th) chromosome
Sex-linked Chromosome Abnormalities
Caused by problems with sex chromosomes

14. Sex-Linked Chromosome Abnormalities
Genetic Foundations
Sex-Linked Chromosome Abnormalities
Klinefelter Syndrome
Males have an extra X chromosome
Fragile X syndrome
Abnormality in the X chromosome
Turner syndrome
Females missing an X chromosome
XYY syndrome
Males have an extra Y chromosome

15. Heredity, Environment, and Individual Differences
Behavior Genetics
Behavior genetics—seeks to discover influence of heredity and environment on individuals
Twin study—behavioral similarity of identical twins compared with fraternal twins
Adoption study—whether adopted children are more like their adoptive parents or their biological parents

16. Genotype-Environment Correlations
Passive
Natural parents provide genetic heritage and rearing environment
Evocative
Child’s genotype elicits certain types of physical and social environments
Active
(niche picking)
Children seek out environments they find compatible and stimulating

17. Shared and Non-Shared Environmental Experiences
Heredity, Environment, and Individual Differences
Shared and Non-Shared Environmental Experiences
Shared environmental experiences—siblings’ common environmental experiences
Non-shared environmental experiences—child’s unique experiences, both within family and outside family, that are not shared by another sibling

18. Heredity, Environment, and Individual Differences
The Epigenetic View
Emphasizes development is result of an ongoing, bi-directional interchange between heredity and environment

19. The Heredity-Environment and Epigenetic Views

20. Conclusions about Heredity-Environment Interaction
Heredity, Environment, and Individual Differences
Conclusions about Heredity-Environment Interaction
Heredity and environment operate together
Relative contributions of heredity and environment are not additive
Many complex behaviors likely have some genetic loading

21. The Germinal Period Takes place in the first 2 weeks after conception
Prenatal Development
The Germinal Period
Takes place in the first 2 weeks after conception
Includes creation of zygote, continued cell division, and attachment of zygote to uterine wall

22. The Embryonic Period Occurs 2 to 8 weeks after conception
Prenatal Development
The Embryonic Period
Occurs 2 to 8 weeks after conception
Rate of cell differentiation intensifies, support systems for cells form, and organs appear

23. The Placenta and the Umbilical Cord
Prenatal Development
The Placenta and the Umbilical Cord

24. Prenatal Development
The Fetal Period
Begins 2 months after conception and lasts for 7 months until birth.
Growth and development continue, features and functions develop.

25. Teratogens and the Prenatal Environment
Prenatal Development
Teratogens and the Prenatal Environment
Teratogen—agent that causes a birth defect
Severity and type of damage influenced by:
Dose
Genetic susceptibility
Time of exposure

26. Prescription and Nonprescription Drugs
Prenatal Development
Prescription and Nonprescription Drugs
Psychoactive Drugs
Alcohol
Fetal alcohol syndrome (FAS)—abnormalities that appears in offspring of mothers who drink alcohol heavily during pregnancy
Nicotine
Cocaine
Marijuana
Heroin

27. Environmental Hazards
Prenatal Development
Environmental Hazards
Lead
Radiation
Certain pesticides
Petrochemicals
Pollutants
Toxic wastes

28. Infectious Diseases Rubella Syphilis Genital herpes AIDS
Prenatal Development
Infectious Diseases
Rubella
Syphilis
Genital herpes
AIDS

29. Incompatible Blood Types
Prenatal Development
Incompatible Blood Types
Blood group
Rh factor

30. Other Parental Factors
Prenatal Development
Other Parental Factors
Nutrition
Maternal Age
Emotional States
Stress

31. The Transition from Fetus to Newborn
Birth
The Transition from Fetus to Newborn
Considerable stress for baby
Adrenaline and noradrenalin secreted
First breaths may be the hardest ones

32. Childbirth Setting and Attendants
In U.S.
99 percent of births take place in hospitals
90 percent are attended by physicians
6 percent attended by midwife

33. Low Birth Weight Infants
Low Birth Weight—born after regular period of gestation but weigh less than 5 and a half pounds
Preterm—born three weeks or more before the pregnancy has reached full term
Small for date—birth weights below normal when length of pregnancy is considered

34. Consequences of Low Birth Weight
Brain injuries
Lung or breathing problems
Liver diseases
More likely to have later learning disability, attention deficit disorder

35. Birth
Apgar Scale
Widely used method to assess the health of newborns at 1 and 5 minutes after birth
Infants’ heart rate
Respiratory effort
Muscle tone
Body color
Reflex irritability

36. Brazelton Neonatal Behavioral Assessment Scale
Birth
Brazelton Neonatal Behavioral Assessment Scale
Given several days after birth to assess:
Neurological development
Reflexes
Reactions to people