1. The following four chemical elements make up 99% of the atoms in the body.

a. Sodium, potassium, calcium and chlorine.

b. Oxygen, nitrogen, hydrogen and carbon.

c. Nitrogen, potassium, oxygen and hydrogen.

d. None of the above. The four main chemical elements make up only 75% of the atoms of the body.

2. The following is true about protons, neutrons and electrons:

a. Protons have one positive charge and about the same mass as an electron.

b. Electrons have one negative charge and have about the same mass as a neutron.

c. Protons and neutrons have about the same mass.

d. All of the above.

3. Covalent bonds are:

a. Formed by the attraction of cations to anions.

b. The second strongest chemical bond between atoms.

c. Formed when the electron in the outer orbit of each of two atoms is shared between the atoms.

4. The following is a carboxyl group:

a. -OH

b. -COOH

c. NH₃

d. C₆H₁₂O₆

5. A solution with pH 9:

a. has a 10⁹ M hydrogen ion concentration

b. is alkaline

c. is acidic

d. is neutral

6. Carbohydrates have the formula:

a. 2C_nH_nO_n

b. C_nH_nO_n

c. C_nH_2nO_n

d. C_2nH_nO_2n

7. The subunit in the glycogen molecule is:

a. sucrose

b. ribose

c. glucose

d. fructose

8. The following is a 5 carbon monosaccharide:

a. glucose

b. sucrose

c. glycogen

d. ribose

9. The following are true of fatty acids except:

a. In saturated fatty acids the carbons in the fatty acid chain all have double bonds.

b. In a mono-unsaturated fatty acid one double bond is present between carbons.

c. In a polyunsaturated fatty acid more than one double bond is present in the carbon chain.

d. They contain a carboxyl group

10. The ring structure of a steroid is represented by which figure?

a. c.

b. d.

11. Proteins are made up of amino acids. There are how many different amino acids in the body?

a. 33

b. 64

c. 20

d. 50,000 or more

12. The compartment labeled A is a: (study Fig 3-4 of your handout).

a. mitochondrion

b. nucleolus

c. microfilament

d. rough endoplasmic reticulum

13. The compartment labeled B is:

a. mitochondria

b. granular (rough) endoplasmic reticulum

c. microfilament

d. nucleolus

14. The main function of mitochondria is:

a. DNA synthesis

b. protein processing and packaging

c. ATP production

d. RNA synthesis

15. The main function of the Golgi apparatus is:

a. DNA synthesis

b. protein processing and packaging

c. ATP synthesis

d. RNA synthesis

16. The following are true of plasma membranes except:

a. They are made up of a double layer of lipid molecules in which proteins are embedded

b. The lipid membranes include phospholipids and cholesterol.

c. The plasma membrane has RNA binding sites on the inside surface of the membrane resembling rough endoplasmic reticulum

d. The plasma membrane has both integral membrane proteins and peripheral membrane proteins

17. The attached illustrates a: (Fig 3-9 of your handout).

a. desmosome

b. tight junction

c. gap junction

Will be on exam but I have no trial questions. Make up your own! Should have some Tuesday, AM.

18. DNA is made up of a double helix of nucleotides. Each nucleotide in DNA consists of:

a. A sugar, a base and a phosphate group.

b. A sugar, an amino acid and a phosphate group

c. A base, an amino acid and a phosphate group.

d. None of the above.

19. The differences between RNA and DNA in the human cell include the following:

a. RNA is a double helix

b. RNA contains the sugar ribose and DNA contains deoxyribose

c. DNA contains the base uracil. RNA does not.

d. There is an RNA polymerase but no DNA polymerase.

20. Purine and pyrimidine bases are bound by hydrogen bonds in the DNA double helix. There are two typical base pair combinations. They include:

a. Guanine to cytosine

b. Adenine to guanine

c. Adenine to thymine

d. a and d

21. In the DNA double helix shown the bases are paired by dashed lines which represent what kind of bonds?

a. covalent bonds

b. ionic bonds

c. james bond

d. hydrogen bonds

22. In DNA base pairing, the purine and pyrimidine bases pair up. The following bases pair up with each other in the DNA molecule:

a. adenine to thymine, guanine to uracil.

b. adenine to guanine, thymine to cytosine.

c. adenine to guanine, cytosine to uracil.

d. adenine to thymine, guanine to cytosine.

23. An RNA polymerase does the following:

a. Joins together aligned RNA nucleotides during RNA synthesis.

b. Breaks down RNA into individual nucleotides.

c. Joins amino acids together that are bound to tRNA during protein synthesis.

d. Converts guanine to cytosine.

24. Transcription is:

a. The synthesis of protein in the cytoplasm from separate amino acids.

b. The synthesis of RNA in the nucleus from a DNA template.

c. The addition of sugars to proteins in glycoprotein synthesis.

25. The following is true regarding ribosomes:

a. They contain no protein.

b. They contain no RNA.

c. They have two tRNA binding sites.

d. They are found only on rough endoplasmic reticulum.

ANSWERS

1. b

2. c

3. c

4. b (somewhat challenging)

5. b

6. c

7. c

8. d (somewhat challenging)

9. a (d somewhat challenging)

10. Fig 2-12

11. c

12. Fig 3-4, know this

13. Fig 3-4, know this

14. c

15. b

16. c (I would not include d in your exam)

17. Fig. 3-9

18. a

19. b (somewhat challenging)

20. d

21. d

22. d (redundant question to 20)

23. a

24. a

25. c (you will learn in chap 7)

1. The backbone that hooks nucleotides together in RNA and DNA is called the __________________ backbone.

2. A molecule of similar repeating units is called a ________.

3. Glycogen, protein, and RNA are examples of these:

a. true

b. false

4. Bacteria are prokaryotic cells because they lack a nucleus.

a. true

b. false

5. The following molecules are involved in unwinding DNA:

a. DNA gyrase

b. DNA helicase

c. DNA unwindase

d. a, b and c

e. a and b only

6. A strand of DNA or RNA that is synthesized from a DNA template strand is called a __________ strand.

7. Because DNA strands are only made in the 5' to 3' direction, the lagging strand

has shorter pieces of DNA called ___________.

8. In the growth cycles of the cell the phases are G1, S, G2 and M. The following is true of G1 and G2:

a. The G stands for growth.

b. DNA is replicated in these phases.

c. a and b

d. None of the above

9. The subunit of RNA that binds to the DNA promotor site is:

a. The kappa subunit

b. The sigma subunit

c. The sticky subunit

10. Gene activator proteins:

a. Help the RNA polymerase recognize the promotor region of DNA so that the RNA polymerase can bind to it.

b. Are often used to turn on housekeeping genes.

c. Are made up of strings of nucleic acids

d. a and c

11. A signal molecule changes the shape of activator and repressor proteins:

a. true

b. false

ANSWERS:

1. sugar-phosphate

2. polymer

3. true

4. true

5. e

6. complementary

7. Ozaki fragments

8. d

9. b

10. a

11. a

1. A regulatory protein controls the expression of a gene or the activity of another protein.

a. true

b. false

2. The heme group in the hemoglobin molecule is an example of a __________.

3. Amino acids are joined by _______ bonds between amino groups and carboxyl groups to form peptide chains.

4. The following influence protein shape:

a. hydrogen bonds

b. hydrophobic and hydrophilic regions

c. covalent bonds

d. all of the above

e. a and c only

5. There are how many possible groups of three bases to code for amino acids?

a. 20

b. 16

c. 64

6. Each amino acid has at least one tRNA molecule with an anticodon for that amino acid:

a. true

b. false

7. To get protein synthesis started, the mRNA must have:

a. A start codon

b. An S-D sequence

c. An activator protein

d. a and b

e. a, b and c

8. The arrival and movement of the components in protein synthesis is supervised by proteins called ________ factors.

9. The first amino acid in a newly formed protein is:

a. N.Y.Met

b. fMet

c. MetLife

d. none of the above

Answers:

1. a

2. cofactor

3. covalent

4. d

5. c

6. a

7. d

8. elongation

9. b