What did I learn?

The following questions will help you review concepts presented in this module.

1. In this module, you learned that hair color might affect the outcome of drug testing. A dark-haired man and a blonde man use cocaine one night at the same time. Upon drug testing one month later, the dark-haired man is denied employment while the blonde man is hired. This happens because the dark-haired man:
   1. Has more keratin in his hair follicles
   2. Has less keratin in his hair follicles
   3. Has more melanin in his hair follicles
   4. Has less melanin in his hair follicles
2. Cocaine, a weak base, can be found in hair. Once in the bloodstream, cocaine can cross the capillary membranes to enter the hair follicle and bind to melanin. Its ability to bind to melanin, an acid, is because it can:
   1. Remove a hydrogen ion, H+, from the melanin
   2. Remove a hydroxide ion, OH-, from the melanin
   3. Add a hydroxide ion, OH-, to the melanin
   4. Add a hydrogen ion, H+, to the melanin
3. This module reminded you that drugs can enter the body in different ways. Drug addicts avoid using methods of administration that result in slow entry into the body or bloodstream because they need to feel the effect of the drug quickly. By which of the following forms of adminstration does a drug get into the bloodstream slowest?
   1. Injection into a vein
   2. Snorting it
   3. Smoking it
   4. Ingestion (by mouth)
4. A drug test is given to a woman applying for a job. The interviewer tells her that traces of cocaine were found in her hair. She claims that she has not used any of the drug. She said it must be because she was near someone who was smoking crack. Upon further investigation, the interviewer believes her because:
   1. Metabolites of cocaine were found in her hair shaft
   2. She had a high level of melanin in her hair
   3. There was no real pattern of cocaine binding to the hair
5. As discussed in this module, the bottom of the hair follicle contains a bulb with cells responsible for making hair.  Higher up in the bulb, the hair is more highly organized into three layers of cells.  The middle layer, or cortex, contains keratinocytes and melanocytes.  What do these cells do?
   1. Destroy keratin and melanin
   2. Destroy carotene and melatonin
   3. Make keratin and melanin
6. Hair color is explained in part by physics and chemistry.  The color of one’s hair is dependent upon the absorption and reflection of light (dictated by the presence of melanin).  Which hair color is the result of the most amount of reflected light?
   1. Blonde
   2. Brown
   3. Black

Now, check your answers here.