Respond in a minimum of 200 words on or before Sunday, June 16th by 11:59 pm.
APPLY: Gilbert’s genetic makeup is homozygous for dark hair. Jan’s is homozygous for blond hair. What color is
Gilbert’s hair? How about Jan’s? What proportion of their children is likely to be dark-haired? Explain. (p. 56)
Referring to ecological systems theory (see Chapter 1, pages 25–27), explain why parents of children with
genetic disorders often experience increased stress. What factors, within and beyond the family, can help these parents
support their children’s development? (pp. 60–61)
Gilbert would have dark hair as his genes are homozygous or the same. In other words, Gilbert inherited two dark haired genes and no light haired genes so his hair will either be black or brown but not red or blonde. Jan is the same way as Gilbert she, though inherited the recessive version of the genes she has two of the same genes for light colored hair. Without the dark haired genes present there is only one hair color type Jan could be and that is light (blonde or red). If Jan and Gilbert had four children at least two would be heterozygous as they would inherit one recessive gene from Jan and one dominant gene from Gilbert and two children would have homozygous as they would take two of the same genes. Child A would have two dominant genes from his dad and so would be dark haired. Child B would have one dominant gene from her dad and one recessive gene from her mom. Since child B would have one of the dominant genes she would also have dark hair. Child C would be like Child B in that he would have two different genes being heterozygous and in being so he would also be dark haired. Child D would have homozygous, recessive genes like her mom and in being so would be light haired like her mom. All-in-all, three of their children would have dark hair. However, hair color is not the only thing inherited from the parents.
Parents who carry the genes for genetic disorders often experience stress because they know there is a chance that their children may come to have the disorders. Much like hair color genes genetic disorders are inherited the same way. Factors within the family that can assist the parents is their family history of disorders and outside the family history the parents can go to certain doctors and have their genes tested for certain disorders. Though it is new, genetic testing can be done and it can show parents what disorders they carry in their own DNA that they may give to their children. Of course couples can also go through genetic counseling too where a family tree is constructed and an action to problems is discussed. Other options after conception to ensure the child has less of a chance of developing a disorder the parents can arrange for a physical exam, reduce or eliminate toxins under their control, and get proper nutrition. If the parents do not like their chances they can discuss adoption instead.