Exam 1 Chapter 2

1) Which of the following statements about the atom  C is FALSE?

B) It has 12 neutrons in its nucleus.

3) Antacids neutralize acid by the following reaction. Identify the salt in the following equation:

C) MgCl2

4) Which of the following statements is FALSE?

B) Water molecules are formed by hydrolysis.

5) Which of the following is the type of bond holding K+ and I- ions in KI?

A) ionic bond

6) Which of the following is the type of bond between molecules of water in a beaker of water?

C) hydrogen bond

7) What is the type of bond holding hydrogen and oxygen atoms in the H2O molecule?

B) covalent bond

8) Identify the following reaction:  Glucose + Fructose → Sucrose + Water

A) dehydration synthesis reaction

9) Identify the following reaction: Lactose + H2O → Glucose + Galactose

B) hydrolysis reaction

10) Identify the following reaction: HCl + NaHCO3 → NaCl + H2CO3

C) exchange reaction

11) Identify the following reaction: NH4OH ⇌ NH3 + H2O

D) reversible reaction

12) Which type of molecule contains the alcohol glycerol?

B) phospholipids

13) Which type of molecule is composed of (CH2O) units?

A) carbohydrate

14) Which type of molecule contains -NH2 groups?

D) protein

15) Which type of molecule NEVER contains a phosphate group?

A) triglycerides

16) Based upon the valence numbers of the elements magnesium (2) and hydrogen (1), predict how many covalent bonds would form between these atoms to achieve the full complement of electrons in their outermost energy shells.

B) two

18) Which of the following statements regarding protein structure is FALSE?

C) Tertiary structures are formed only from covalent bonds.

19) Which of the following pairs is mismatched?

D) KH2PO4 ⇌ K+ + H2PO4- — acid

21) What is the type of bond between the hydrogen of one molecule and the nitrogen of another

molecule?

C) hydrogen bond

22) What is the type of bond between carbon, hydrogen, and oxygen atoms in organic molecules?

B) covalent bond

23) What is the type of bond between ions in salt?

A) ionic bond

24) A scientist wants to perform a test that will indicate whether a nucleic acid sample is composed of RNA or DNA. Testing for the presence of which of the following is most appropriate in this situation?

D) uracil

25) If you viewed one single protein using a microscope, you would observe multiple ________ structures.

B) secondary

26) Two antiparallel strands of DNA combine to form a double helix. The specific interactions that permit this phenomenon occur by way of ________ bonds between ________.

B) hydrogen; nitrogenous bases

27) Structurally, ATP is most like which type of molecule?

D) nucleic acid

28) What do genes consist of?

D) nucleic acids

29) Which molecule is composed of a chain of amino acids?

C) protein

30) Which are the primary molecules making up plasma membranes in cells?

B) lipids

31) The antimicrobial drug imidazole inhibits sterol synthesis. This would most likely interfere with

C) eukaryotic plasma membranes.

36) Most amino acids found in cells demonstrate what type of chirality?

A) L-iosmers

38) An E. coli culture that has been growing at 37°C is moved to 25°C. Which of the following changes must be made in its plasma membrane?

D) The number of unsaturated chains must increase.

39) Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope 35S. After a 48-hour incubation, the 35S would most likely be found in the S. cerevisiae's

E) proteins.

40) Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope 32P. After a 48-hour incubation, the majority of the 32P would be found in the S. cerevisiae's

A) plasma membrane.

41) Starch, dextran, glycogen, and cellulose are polymers of

B) glucose.

42) Which of the following is a base?

C) NaOH → Na+ + OH-

43) Two glucose molecules are combined to make a maltose molecule. What is the chemical formula for maltose?

D) C12H22O11

44) Desulfovibrio bacteria can perform the following reaction: S6- → S2-. These bacteria are

D) oxidizing sulfur.

45) If an amino acid contained a hydrocarbon as its side group, in which of the following categories could it be appropriately designated?

C) nonpolar