chapter 5

• dominant trait


  a genetic trait that is considered dominant if it is expressed in a person who has only one copy of that gene
• color blindness

  • a genetic (hereditary) condition (you are born with it)
  • Red/green and blue color blindness is usually passed down from your parents.
  • Carried on the X chromosome
  • More men are affected than women
• female chromosomes



  female have two X chromosomes
• Male Chromosomes


  Males have one X and one Y chromosome
• Chromosomes


  strands of hereditary material

  • Each human nucleus has 23 pairs (except egg and sperm have 23 single, unpaired)Genes: sections along each chromosome that controls the chemical reactions that direct development
• genetic principles

  • chromosomes
  • genes
• Monozygotic Twins

  • SINGLE FERTILIZED EGG
  • IDENTICAL GENES
  • IDENTICAL TWINS
• Dizygotic Twins

  • TWO EGGS
  • SHARE ONLY HALF THEIR GENES
  • FRATERNAL TWINS
• Cross-Sectional 


  compares groups of individuals with different ages at the same time
• Longitudinal Design


  follows a single group of individuals as they develop
• Sequential Design


  A researcher starts with people of different ages and studies them again at later times
• The Fetus and the Newborn

  • Zygote-fertilized egg cell
  • Embryo- unborn child until the end of the seventh week following conception
  • Fetus- 8 weeks after conception
• Infants’ Hearing

  • Habituation- decreased response to a repeated stimulus
  • Dishabituation-when a change in a stimulus increases a previously habituated response
• Jean Piaget 


  was a Swiss psychologist and genetic epistemologist. He is most famously known for his theory of cognitive development
• New processes

  • schema- an organized way of interacting with objects
  • assimilation- applying an old schema to new objects or problems
  • accomodation- modifying an old schema to fit a new object or problem
  • equilibration- the establishment of harmony or balance between assimilation and accomodation
• • sensorimotor(0-2) - coordination of senses with motor response.
  • Preoperational(2-7) - symbolic thinking, use of proper syntax and grammar express full concepts.
  • Concrete Operational(7-11) - concepts attached to concrete situations. they begin to understand time, space, and quantity.
  • Formal Operations(11+) - Theorica, hypothetical, and counterfactual thinking. abstract logic and reasoning. Strategy and planning become possible.
• identity development


  adolecence is a time of:

  • finding yourself
  • determining ¨who am I?¨
  • determining ¨who will I be?¨
• identity crisis


  anadolescent´s concern with decision about the future and the quest for self understanding
• identity development

  • identity diffusion: no clear sense of identity.
  • identity moratorium: considering the issues but not yet making decisions.
  • identity foreclousure: reaching firm decisions without much thought.
  • identity achievement: the outcome of havinf explored various possible identities and then making one´s own decision.
• gender roles


  also known as sex roles, the different activities that society expects of males and females
• parenting styles

  • authoritative parents- set high standards, impose controls, Set limits but adjust when appropriate
  • Authoritarian Parents- Set firm controls, Emotionally distant from child, Set rules without explaining the reasons behind them.
  • Permissive Parent- Warm and loving, Undemanding, More like a friend than a parent
  • Indifferent or Uninvolved Parents- Spend little time with their children, Do the minimum of providing food and shelter