Exam 1 Questions Flashcards
What are the major molecular interactions that stabilize alpha helical structures in proteins?
H-bonds are the major molecular interaction involved in the formation of alpha helix.
What atoms are involved in hydrogen bonding?
H-bonds are formed between the O and NH- in a peptide linkage with NH- and O in another peptide linkage either one helical turn above or below.
How can glyceraldehyde be converted into a component of a typical biological membrane?
Glyceraldehyde can be reduced to glycerol, a key part of phospholipids that are abundant in biological membranes.
Why are plant lipids liquid at room temperature, but animal lipids solid?
Plant lipids contain polyunsaturated fatty acids with multiple double bonds with a bent structure. This makes them more fluid than animal lipids containing very little polyunsaturated fatty acids. More fluid lipids result in a lower melting temperature.
How can soaps be used to remove greases from dirty clothes?
Sodium salt of fatty acid is dissociated to form negatively charged fatty acid and positively charge sodium ion. Being ampiphilic molecules, a group of fatty acids will form a micelle with hydrophillic acid groups facing outside in contact with water, and hydrophobic hydrocarbon tails aggregated in the center. The hydrophobic interior merges with the hydrophobic grease and then is washed away by water.
How can cholesterol affect the property of a biological membrane?
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