Condensation and Hydrolysis Reactions
Which molecule is not a carbohydrate?
lipids A lipid is a hydrophobic polymer, not a carbohydrate.
How many molecules of water are used to completely hydrolyze a polymer that is 11 monomers long?
10
Which of the following statements about the formation of polypeptides from amino acids is true?
A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.
Which complex carbohydrate contains only a-1,4-glycosidic linkages?
Amylose Amylose is formed from a-1,4-glycosidic linkages of glucose.
Which of the following is not attached to the central carbon atom in an amino acid?
An oxygen The central carbon atom in an amino acid is bonded to an amino functional group, a carboxyl functional group, a side chain, and hydrogen.
Carbohydrates
Broken down to glucose to provide energy. Body's main source of energy
Which part of an amino acid is always acidic?
Carboxyl functional group The carboxyl group (COOH) contains two oxygen atoms that tend to pull electrons away from the hydrogen atom, so this group tends to lose a proton and is acidic.
Which of these is a polysaccharide?
Cellulose is a carbohydrate composed of many monomers.
Plant cell walls consist mainly of _____.
Cellulose Cellulose is a polysaccharide that is a major component of the tough walls that enclose plant cells.
The most abundant organic compound on Earth. Is
Cellulose, a component of plant cell walls, is the most abundant organic compound found on earth.
Which of the following complex carbohydrates is listed with its correct function?
Cellulose: structural component of plant cell walls Cellulose is indeed the main structural component of plant cells walls.
Sucrose is formed when glucose is joined to fructose by a(n) _____.
Glycosidic linkages Glycosidic linkages join simple sugars to form polysaccharides.
Which of these classes of biological molecules does NOT include polymers?
Lipids
Which of these is a source of lactose?
Milk Lactose is the sugar found in milk.
Which of the following statements about monosaccharide structure is true?
Monosaccharides can be classified according to the spatial arrangement of their atoms.
Which monomers make up RNA?
Nucleotide Nucleotide monomers make up nucleic acids.
Which polysaccharide contains a modified monosaccharide?
Peptidoglycan The N-acetylglucosamine and N-acetylmuramic acid units that make up peptidoglycan are composed of modified glucose monomers.
chitin
Polysaccharide found in arthropod exoskeletons and fungal cell walls.
Which polymers are composed of amino acids?
Proteins. Proteins are composed of amino acids joined together.
All carbohydrates have the general formula Cn(H2O)n.
This formula only applies to simple sugars, which are equal parts carbon and water. Complex sugars, which do not have this general formula, are also carbohydrates.
True or false? Peptidoglycan is a polysaccharide found only in bacteria.
True
True or false? Enzymes in the digestive tract catalyze hydrolysis reactions.
True Enzymes in the digestive tract break down food molecules, which is a process that occurs by hydrolysis.
Glycogen is ____
a polysaccharide found in animals Animals store energy in the form of glycogen.
Starch and cellulose _____.
are polymers of glucose
Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?
as a disaccharide
Which polysaccharide is an important component in the structure of many animals and fungi?
chitin
Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
dehydration reactions assemble polymers; hydrolysis reactions break polymers apart.
Which of the following is NOT a polymer?
glucose, but starch cellulose DNA are polymers
Humans can digest starch but not cellulose because _____.
humans have enzymes that can hydrolyze the α-glycosidic linkages of starch but not the β-glycosidic linkages of cellulose
glucose + glucose —> _____ by _____.
maltose + water ... dehydration synthesis Maltose is the disaccharide formed when two glucose molecules are linked by dehydration synthesis.
Polymers that contain sugars ...
may store hereditary information. (b) may store energy. (c) may protect cells. Polymers that contain sugars do all, they also lubricate the path of roots through soil and they glue plant cells together.
A molecule with the chemical formula C6H12O6 is probably a _____.
monosaccharide
The four main categories of large biological molecules present in living systems are _____.
proteins, nucleic acids, polysaccharides, and lipids