Unit 2 Exam

1. In a water molecule, hydrogen and oxygen are held together by a(an) ______ bond.

  double covalent 
  ionic 
  nonpolar covalent 
  hydrogen 
  polar covalent 
 

2. An atom that emits energy in an attempt to attain a more stable state is said to be

  energetic 
  hyperexcitable 
  reactive 
  radioactive 
  inert 
 

3. Which of the following is an acid?

  NaOH 
  NaCl 
  HCl 
  H 2O
  CH 4
 

4. Why is water considered a polar molecule?

  The oxygen is found between the two hydrogens. 
  The negatively charged oxygen atom attracts the positively charged hydrogen atoms. 
  It remains liquid even at very low temperatures. 
  Its electrons spend more time with its oxygen than with either hydrogen. 
  Both hydrogens are at one end of the molecule, and oxygen is at the other end. 
 

5. What name is given to the following reaction?

glycerol + fatty acid → monoglyceride + water
  denaturation 
  hydrolysis 
  hydrogenation 
  catabolism 
  synthesis 
 

6. The primary structure of a protein is ______.

  an ∝ (alpha) helix or a pleated sheet 
  the amino acid sequence of the polypeptide chain 
  composed of two or more polypeptide chains 
  maintained by hydrogen bonds 
  irregular folding 
 

7. What name is given to the following reaction?

galactose + glucose → lactose + water
  hydrolysis 
  hydrogenation 
  glycolysis 
  dehydration synthesis 
  gluconeogenesis 
 

8. What is the name given to the reaction that breaks peptide bonds?

  synthesis 
  hydrogenation 
  hydrolysis 
  anabolism 
  denaturation 
 

9. Table sugar is ______.

  glucose 
  maltose 
  lactose 
  sucrose 
  fructose 
 

10. Which of the following is a function of the plasma membrane?

  control center of the cell 
  protein synthesis 
  fat synthesis 
  regulation of the passage of material into and out of the cell 
  intracellular digestion 
 

11. Which organelle is responsible for photosynthesis?

  smooth endoplasmic reticulum 
  mitochondrion 
  ribosome 
  chloroplast 
  nucleolus 
 

12. ______ are the major lipids of plasma membranes.

  Steroids 
  Triglycerides 
  Prostaglandins 
  Mosaics 
  Phospholipids 
 

13. When digested, nucleic acids are broken down into ______.

  fatty acids 
  monosaccharides 
  glycerols 
  nucleotides 
  amino acids 
 

14. The esophagus and trachea are both open to the ______.

  pharynx 
  posterior oral cavity 
  posterior nasal cavity 
  larynx 
  epiglottis 
 

15. The function of the sphincter at the downstream end of the stomach is to ______.

  retain acid chyme in the stomach until pepsin digestion is complete 
  release acid chyme into the duodenum in periodic squirts 
  release bile into the duodenum when chyme is present 
  release bile and pancreatic secretions into the duodenum when chyme is present 
  release pancreatic secretions into the duodenum when chyme is present 
 

16. The stomach’s gastric glands secrete ______.

  mucus only 
  digestive enzymes only 
  hydrochloric acid only 
  digestive enzymes and hydrochloric acid 
  mucus, digestive enzymes, and hydrochloric acid 
 

17. Which of the following nutrients begins undergoing digestion only when it reaches the small intestine?

  fat 
  protein 
  starch 
  complex carbohydrate 
  polypeptide 
 

18. A balloon permeable to water but not to glucose contains a 10% glucose solution. A beaker contains a 5% glucose solution. Which of the following is true?

  The solution in the beaker is hypertonic relative to the solution in the balloon. 
  The solution in the balloon is isotonic; the solution in the beaker is hypertonic. 
  When placed in the beaker, the balloon will lose water by osmosis. 
  When placed in the beaker, the balloon will experience neither a net gain nor a net loss of water. 
  The solution in the balloon is hypertonic relative to the solution in the beaker. 
 

19. Osmosis can be defined as ______.

  the diffusion of water 
  the diffusion of nonpolar molecules 
  active transport 
  the diffusion of a solute 
  endocytosis 
 

20. The fragrance of bread baking in a kitchen spreads to other rooms by

  active transport 
  osmosis 
  diffusion 
  selective permeation 
  magic 
 

21. The number of electrons surrounding an atom’s nucleus never changes.

  True 
  False 

22. Phosopholipids are found in cell membranes.

  True 
  False 
 

23. When choosing the healthiest type of fat to include in a diet, an individual should include more saturated fat than unsaturated fat because saturated fat appears to decrease the risk of heart disease.

  True 
  False 
 

24. Animal and plant cells contain organelles.

  True 
  False 
 

25. Because they are not soluble in water, fats are digested in a different way than proteins and carbohydrates.

  True 
  False