Shown here are the structures of fructose and glucose. These two molecules are
Which of the following statements correctly describes geometric isomers?
They have variations in arrangement around a double bond
They have an asymmetric carbon that makes them mirror images
They have the same chemical properties
They have different molecular formulas
Their atoms and bonds are arranged in different sequences
Research indicates the Ibuprofen, a drug used to relieve inflammation and pain, is a mixture of two enantiomers; that is, molecules that
have identical three-dimensional shapes
are mirror images of one another
lack an asymmetric carbon
differ in the location of their double bonds
differ in electrical charge
Research indicates that Albuterol, a drug used to relax bronchial muscles, improving airflow and thus offering relief from asthma, consists only of one enantiomer, the R- form. Why is it important for this drug to consist of only one enantiomer form, rather than a mixture of enantiomers?
Different enantiomers may have different or opposite physiological effects
It is impossible to synthesize mixtures of enantiomers
It is much less expensive to synthesize one enantiomer at a time
Albuterol is an example of a compound for which only one enantiomer exists
Only the R-form of Albuterol has been studied; until more information is available, physicians prefer to use the pure R- form.
Which of the following is TRUE of both starch and cellulose?
They are both polymers of glucose
They are geometric isomers of each other.
They can both be digested by humans
They are both used for energy storage in plants
They are both structural components of the cell wall
Which of the following is true of cellulose?
It is a polymer composed of sucrose monomers
It is a storage polysaccharide for energy in plant cells
It is a storage polysaccharide for energy in animal cells
It is a major structural component of plant cell walls
It is a major structural component of animal cell plasma membranes.
Humans can digest starch but not cellulose because
the monomer of of starch is glucose, while the monomer of cellulose is galactose
human has enzymes that can hydrolyze the beta glycosidic linkages of starch but no the alpha glycosidic linkages of cellulose
Humans have enzymes that can hydrolyzes the alpha glycosidic linkages of starch but not the beta glycosidic linkages of cellulose
humans harbor starch-digesting bacteria in the digestive tract
the monomer of starch is glucose, while the monomer of cellulose is maltose
All of the following statements concerning saturated fats are true except
They are more common in animals than in plants
They have multiple double bonds in the carbon chains of their fatty acids
They generally solidify at room temperature
They contain more hydrogen than unsaturated fats having the same number of carbon atoms
They are one of several factors that contribute to atherosclerosis.
The R group or side chain of the amino acid serine is -CH2 -OH. The R group or side chain of the amino acid alanine is -CH3. Where would you expect to find these amino acids in a globular protein in aqueous solution?
Serine would be in the interior, and alanine would be on the exterior of the globular protein.
Alanine would be in the interior, and serine would be on the exterior of the globular protein.
Both serine and alanine would be on the interior of the globular protein.
Both serine and alanine would be on the exterior of the globular protein.
Both serine and alanine would be in the interior and exterior of the globular protein.
If one strand of a DNA molecule has the sequence of bases 5' ATTGCA3' the other complementary strand would have the sequence
5' UAACGU 3'
Why are human sex hormones considered to be lipids?
They are essential components of cell membranes.
They are steroids, which are not soluble in water.
They are made of fatty acids
They are hydrophilic compounds
They contribute to atherosclerosis
If 2 molecules of the general type showing in this figure were linked together carbon 1 of one molecule to carbon 4 of the other, the single molecule that would result would be