Homework 4

Heredity and Behavior –Due August 25th.

  1. Define ADHD. What evidence is there of a genetic component to this disorder? (3 points).

ADHD stands for Attention Deficit Hyperactivity Disorder, which isa common problem to children and sometimes extent to adolescent. Itfactors into consideration numerous behavioral symptoms that includeimpulsiveness, hyperactivity and inattentiveness. Moreover, ADHD hasthree important sub groups, which are predominantly inattentive,predominantly hyperactive-impulse, and combined hyperactiveinattentive and impulsive. Some of the causes of the conditioninclude genetic make up. Research has shown that genetic make upshows the issue is based on genetics based on research carried out ontwins. It is attributed to thin tissues that are on the brain.

  1. In your own words, describe the two types of non-additive genetic effects (2 points).

Non-additive genetic effects can be defined as the interactionsthat exist among alleles both across and within gene loci. The twoeffects are dominance and epistasis. Dominance is single locus whileepistasis refers to alleles from different loci (across).

  1. Describe two pieces of evidence that indicate that genetic influences on cognitive ability change over a person’s life (2 points).

Access to resources and environmental conditions usuallyinfluences the future of a person. For example, a privileged childaccesses appropriate resources within a suitable environment meaningthat the individual is better positioned to become more superior whencompared to a person with similar or same genetic make up placed in adisadvantaged environment. In addition, availability of economiccapacity to an individual enables the individual to capitalize on thegenetic influences in advancing their own requirements/expectations.

  1. Discuss findings from two studies that support a genetic basis for autism (2 points).

According to Eapen (2011), there is a direct relationship betweengenes and autism. Eapen (2011) argues there are interactions betweenenvironmental, epigenetic and genetic factors in understandingautism. Moreover, Kumar&amp Christian (2009) conquers there areevidence that indicates autism is associated with genetic etiology.Even though numerous genetic bases exist, studies have employed anarray of techniques.

  1. Which of the following best represents a genotype-environment interaction in research on maze-bright and maze-dull rats? (e. none of the above)

    1. Enriched early environments improved performance in maze-dull rats but not maze-bright rats

    2. Maze-bright rats performed better than maze-dull rats regardless of upbringing

    3. The offspring of maze-bright rats are also maze-bright

    4. Maze-bright rats showed no improvement regardless of environment

    5. None of the above


Eapen, V. (2011). Genetic basis of autism: is there a way forward?Curr Opin Psychiatry, 24(3), 226-36

Kumar, R., &amp Christian, S. (2009). Genetics of autism spectrumdisorders. Curr Neurol Neurosci Rep., 9(3), 188-97.