Question

2) At a pH greater than that of its isoelectric point, the structure of glycine is a) H-CH-COOH b) H-CH-C00- c) H-CH-CO e) H-CH-COO COOH b) H-CH-C00- c) H-CH-COOH d) H-CH-COO NH2 NH2 NH2 NH3 NH 3) Which of the following structures can be destroyed by the dena structures can be destroyed by the denaturation of a protein? a) Only primary and tertiary structures of a protein. b) Only secondary, tertiary y secondary, tertiary, and quaternary structures of a protein. c) Only primary, secondary, and tertiary structures of a protein. d) Only primary, secondary, and quaternary structures of a protein. e) Only secondary and tertiary structures of a protein. The secondary structure of proteins is the result of a) Hydrogen bonding between a backbone -C=O group and an R group. b) Hydrogen bonding between a backbone -C=0 group and a backbone -N-H group. c) Hydrogen bonding between an R group and a backbone -N-H group. d) Hydrogen bonding between two different R groups. e) hydrophobic interactions between two different Rgroups. Which of the following interactions can stabilize the tertiary structure of proteins? a) Disulfide bonds. b) Hydrogen bonding. c) Salt bridges. d) Hydrophobic interactions. e) All of the above. 6) Which of the following describes the way in which two or more polypeptide chains fit together in a protein? <) a) Primary structure of a protein b) Secondary structure of a protein c) Tertiary structure of a protein d) Quaternary structure of a protein e) Hydrophobic structure of a protein Scanned with CamScanner

Answer 1

sol:-

isoelectric point = tha point in which amino acid does not move in electric field.means neutral ion formation. so neutral structure of gylcine will be at isoelectric point.

2):- (b)

H-CH-cool zwitter ion. NH2
3):- denaturation :- breaking of secondary and tertiary structure of protein

so, (e) only secondary and tertiary structure of protein.

4):-secondary structure of protein is the result of hydrogen bonding between a backbone -C=O group and a backbone of -N-H group.

5):-teriary structure is stabilised by following interaction:-

• hydrogen bonding
• disulfide bonds
• hydrophobic interaction
• salt bridges

6):-two or more polypeptide fit togather in protein of quaternary structure of protein