The Development Of Children Chapter 2 The Human Heritage: Genes and the Environment The Human Heritage: Genes and the Environment

Bottom Line 1 - Terms to know in Ch 2 Mitosis and Meiosis Chromosomes: Males have XY and Females have XX chromosomes Genes DNA Dominant and Recessive Genes Mitosis and Meiosis Chromosomes: Males have XY and Females have XX chromosomes Genes DNA Dominant and Recessive Genes

Bottom Line 2 Concepts to know in Ch 2 Genetics + Environment = Characteristics Sex-linked characteristics Gene-environment interaction - bunnies! Genes and behavior - family, twin and adoption studies Causes of Genetic Abnormalities (Down Syndrome, PKU, Sickle Cell anemia, Klinefelter Syndrome) Genetics + Environment = Characteristics Sex-linked characteristics Gene-environment interaction - bunnies! Genes and behavior - family, twin and adoption studies Causes of Genetic Abnormalities (Down Syndrome, PKU, Sickle Cell anemia, Klinefelter Syndrome)

Down Syndrome Cause: 3 (vs. 2) copies of chromosome 21 Traits: Mentally/physically retarded and distinctive physical characteristics Incidence: 1:1000 births Outlook: Special education markedly improve intellectual, social, physical and creative functioning Cause: 3 (vs. 2) copies of chromosome 21 Traits: Mentally/physically retarded and distinctive physical characteristics Incidence: 1:1000 births Outlook: Special education markedly improve intellectual, social, physical and creative functioning

Phenylketonuria (PKU) Cause: Defective recessive gene resulting in retarded development of prefrontal cortex Traits: Severe retardation Incidence: 1:10,000 Outlook: Feeding PKU infants a diet avoiding milk, eggs, bread, fish reduces the severity of mental retardation Cause: Defective recessive gene resulting in retarded development of prefrontal cortex Traits: Severe retardation Incidence: 1:10,000 Outlook: Feeding PKU infants a diet avoiding milk, eggs, bread, fish reduces the severity of mental retardation

Sickle-Cell Anemia Cause: Recessive gene (victims are homozygous, but heterozygous subjects are also mildly affected) Traits: Abnormal blood cells cause circulatory problems (e.g., heart enlargement) and severe anemia Incidence: 8-9% of U.S. blacks Outlook: Crippling, but treatable with medication Cause: Recessive gene (victims are homozygous, but heterozygous subjects are also mildly affected) Traits: Abnormal blood cells cause circulatory problems (e.g., heart enlargement) and severe anemia Incidence: 8-9% of U.S. blacks Outlook: Crippling, but treatable with medication

Klinefelter Syndrome Cause: Extra X chromosome (i.e., XXY) Traits: Males fail to develop secondary sex characteristics (e.g., facial hair, voice change), are sterile, and most have speech and language problems Incidence: 1:900 males Outlook: May be treatable with testosterone replacement therapy Cause: Extra X chromosome (i.e., XXY) Traits: Males fail to develop secondary sex characteristics (e.g., facial hair, voice change), are sterile, and most have speech and language problems Incidence: 1:900 males Outlook: May be treatable with testosterone replacement therapy

Survival Strategies: Culture Cultural artifacts, such as tools and clothing, greatly extend the range of environments in which human beings can reproduce and thrive Cultural knowledge, such as the creation of “hazard prevention strategies,” serves to protect and support children to enable them to mature and reproduce Cultural artifacts, such as tools and clothing, greatly extend the range of environments in which human beings can reproduce and thrive Cultural knowledge, such as the creation of “hazard prevention strategies,” serves to protect and support children to enable them to mature and reproduce