Biol 212

What kinds of bonds are broken when water is boiled?

• Hydrophobic bonds

• Polar covalent bonds

• Hydrogen bonds

• Nonpolar covalent bonds

What kinds of bonds are broken when table salt (NaCl) dissolves in water?

•  

  Ionic bonds

  
  

• Hydrogen bonds

• Polar covalent bonds

• Nonpolar covalent bonds

How many single covalent bonds can a carbon atom make?

• 4

• 1

• 2

• 8

Covalent bonds join atoms together in molecules.  Some bonds are polar while others are nonpolar. The atoms joined by a nonpolar bond generally have .......

• Similar electronegatively

• No electronegativity

• Dissimilar electronegativity

Black tea has a reported pH of about 5, while Coke Classic is 2.4.  Which between the two is more acidic?

•  

  Coke Classic

  
  

• Black tea

• Cannot tell from the information given

What properties make water an excellent solvent?

• Non-polarity, bent molecular shape, covalent bonding

•  

  Polarity, bent molecular shape, hydrogen bonding

  
  

• Non-polarity, bent molecular shape, hydrogen bonding

• Polarity, bent molecular shape, covalent bonding

There are 20 different amino acids. What differentiates one amino acid from another?

• Different side chains (R-groups) attached to a carboxyl carbon

• Different side chains (R-groups) attached to an α carbon atom

• Different structural and optical isomers

• Different side chains (R-groups) attached to the amino groups

A peptide bond is formed between two amino acids when the following functional groups are covalently linked by dehydration synthesis/ condensation reaction.....

• Carboxyl and phosphate groups

• Sulfhydryl and phosphate groups

• Hydroxyl and carbonyl groups

• Amino and carboxyl groups

The amino acids of the protein keratin are arranged predominantly in an α-helix. This secondary structure of an α-helix is stabilized by ________.

• peptide bonds

• hydrogen bonds

• covalent bonds

• ionic bonds

The tertiary structure of a protein is the ________.

•  

  order in which amino acids are joined in a polypeptide chain

  
  

• bonding together of several polypeptide chains by weak bonds

• organization of a polypeptide chain into an α-helix or β-pleated sheet

• unique three-dimensional shape of the fully folded polypeptide