Correct answers are in bold, but be sure to read why the other answers are not correct.

1. Alcohol exposure to the developing fetus is harmful during this stage of pregnancy:
   1. the first trimester
      This is partly correct. Exposure of the fetus to alcohol causes damage to its development any time during pregnancy.
   2. the second trimester
      This is partly correct. Exposure of the fetus to alcohol causes damage to its development any time during pregnancy.
   3. the third trimester
      This is partly correct. Exposure of the fetus to alcohol causes damage to its development any time during pregnancy.
   4. all of the above
      Yes, you are correct! Exposure of the fetus to alcohol cause damage to its development any time during pregnancy. The brain is exquisitely sensitive to alcohol during fetal development, young adulthood, and even older ages!
2. The hippocampus is a region of the brain that is responsible for which functions:
   1. motor function
      No. Motor function is governed by the cerebral cortex. The main function of the hippocampus is to help you learn and remember.
   2. attention
      Not really. The cerebral cortex is important in attention. The main function of the hippocampus is to help you learn and remember.
   3. learning and memory
      Perfect. The main function of the hippocampus is to help you learn and remember.</strong
   4. executive function
      No. The cerebral cortex is important in executive functioning. The main function of the hippocampus is to help you learn and remember.>
3. Alcohol can easily pass from the mother’s blood to the fetus because of which property:
   1. polarity
      Not quite.  A polar molecule that is large won’t get through the mother’s bloodstream to the fetal bloodstream.  Only very small molecules (like ethanol) that have some lipophilic properties will get through.
   2. boiling point
      The boiling point has nothing to do with the molecule’s ability to cross a blood vessel. Only very small molecules (like ethanol) that have some lipophilic properties will get through.
   3. small molecular size
      Yes!  Only very small molecules (like ethanol), even if polar, will get through.
   4. viscosity
      The viscosity has nothing to do with the molecule’s ability to cross a blood vessel. Only very small molecules (like ethanol) will get through.
4. Reactive oxygen species are formed when:
   1. oxygen combines with hydrogen
      No. When oxygen combines with hydrogen it forms a hydroxyl molecule: OH
   2. oxygen “steals” an electron from another molecule
      Yes! A reactive oxygen species is formed when an oxygen “grabs” an electron from another molecule. This generates a very unstable form of oxygen like superoxide O2•- (it’s reactive!) because it has an unpaired electron in its outer shell.
   3. oxygen donates a proton to another molecule
      No. Oxygen does not have a proton to donate to any other molecule.
   4. oxygen reacts with another oxygen
      No. Under normal conditions, oxygen does not react with itself. However, the molecule O2 has 2 unpaired electrons, helping to form a double covalent bond between the two oxygen atoms.