Heredity Transmission of characteristics from parents to offspring Plays a key role in the development of traits Height, eye color, etc. Could be involved in many psychological disorders: Depression Schizophrenia Bipolar disorder Alcoholism
Genes and Chromosomes Genes- basic building blocks of heredity Determined by pairs- one gene from each parent Chromosomes Made up of genes Most normal human cells contain 46 chromosomes When this does occur- a disability may occur Down syndrome occurs when there is an extra chromosome on the 21st pair 22 of the 23 pairs for male and female are the same The 23rd pair will determine whether we are male or female
Nature-nurture debate Nature- refers to what people inherit from their parents Nurture- refers to a variety of factors such as education, culture, living conditions Debate over which (nature or nurture) has a greater impact on the kind of person that you become
Kinship studies Twin Studies- used to determine how much genetics determine who we are Identical twins share the same genetic makeup, so differences must be caused by the environment (nurture) Fraternal twins only share some of their genes so differences could be caused by genetics or the environment Identical twins are more likely to share disorders such as autism, substance abuse, and schizophrenia The problem with twin studies is that they grow up together and therefore, have the same genes but also the same environment
Identical twins Share the same genes and environment
Fraternal twins A million to one odds: one black baby and one white
Nature Vs. nurture debate Questions to think about: How are differences in intelligence, personality, and psychological disorders influenced by heredity and environment? Is sexual orientation biologically predisposed or learned? Should we treat depression as a disorder of the brain or a disorder of thought or both?