HUMAN DEVELOPMENT

• Human development- scientific study of changes that occur in the human life span, from conception to death.
• Designs used for research age related changes.

  • longitudinal design
  • cross-sectional design
• Longitudinal design - follow individuals over time as they grow older
• Cohort effect - particular impact on development that occurs when a group of people share a common time period or common life experience.
• Cross-sequential design - a combination of the longitudinal and cross sectional design.
• cross sectional design- several different age groups are studied one at a time.
• longitudinal design- one group of people is studied over time, to see how they change over time
• nature- genetics, hereditary
• nurture- environmental influences
• genetics- science of heredity
• DNA- deoxyribonucleic acid, the molecule that carries genetic information. it contains amines
• 46 chromosomes found in the nucleus of the cell. 23 from each parent
• dominant genes- genes that are expressed in all cells of the organism. expressed in observable trait.
• recessive genes-

  • less active, only expressed if both alleles are recessive.
• Genotype- the genetic makeup of an organism, including the alleles it carries
• fertilization- sperm and egg unite to form a zygote
• zygote- fertilized egg, diploid, contains 23 chromosomes
• twins- identical and fraternal twins
• identical twins- monozygotic twins

  • came from one egg
• fraternal twins- dizygotic twins

  • two eggs are fertilized
• germinal period of pregnancy- 14 days to 2 weeks

  • zygote begins to divide.
• embryonic period- 2 weeks to 8 weeks of gestation, the embryo is a ball of cells with a yolk sac
• embryo- the developing organism from fertilization to birth, including the period of development in the womb
• critical periods- embryo begins to receive nourishment from the mother through placenta.

  • it becomes vulnerable to hazards such as diseases, and toxins.
• teratogen- a substance that causes birth defects in the fetus. such as drug, chemical, virus etc.
• fetal alcohol syndrome- caused by alcohol in pregnancy
• fetal period- 12-20 weeks of gestation, fetus is 1-2 inches long

  • time for miscarriage and spontaneous abortion
• reflexes- infants innate involuntary behavior patterns.
• piaget’s Theory of Cognitive Development: cognitive development is a gradual process that occurs in 4 stages
• sensorimotor stage (birth - age 2) – babies are born with no knowledge about their world; they rely on sensory experiences and motor skills to explore and understand their environment
• preoperational stage (ages 2–7): children begin to use symbols or words to represent objects and events in the real world. They can think logically but only within concrete situations.
• concrete operational stage (ages 7–11): children develop logical thinking abilities and can reason about concrete problems. They have difficulty understanding abstract concepts.
• formal operational stage (age 11+): adolescents develop the ability to reason abstractly and hypothesize about cause-and-effect relationships.
• formal operational stage (age 11+): adolescents and adults can think abstractly and hypothesize about complex ideas and relationships.
• Piaget believed that children construct their own theories about how the world works through active exploration and interaction with the environment.
• Vygotsky's theory of social learning emphasizes the role of culture and language in shaping human cognition.
• temperament- the way an individual reacts to the environment, including their emotional responses
• object permanence- the knowledge that an object exists even when it is not in sight.
• egocentrism- the inability to see the world through anyone else’s eyes but one’s own
• centration- Focusing only on one feature of some object rather than taking all features into consideration