Chapter 5: Structure & Function of Large Biological Molecules

The components of nucleic acids are __________. a nitrogenous base and a phosphate a nitrogenous base and a pentose sugar a nitrogenous base, a pentose sugar, and a phosphate a nitrogenous base and a hexose sugar a nitrogenous base, a hexose sugar, and a phosphate

a nitrogenous base, a pentose sugar, and a phosphate

The subunits (monomers) in cellulose are linked together by __________. ionic bonds peptide bonds phosphodiester linkages ester linkages glycosidic linkages

glycosidic linkages

The secondary structure of a peptide backbone is stabilized by __________ forming either a(n) __________ or a(n) __________. hydrogen bonds; α helix; β pleated sheet ionic bonds; α helix; β pleated sheet covalent bonds; α helix; β pleated sheet covalent bonds; β helix; α pleated sheet hydrogen bonds; β helix; α pleated sheet

hydrogen bonds; α helix; β pleated sheet

One characteristic shared by sucrose, lactose, and maltose is that __________. they are all polysaccharides they all contain fructose they are all monosaccharides they are all indigestible by humans they are all disaccharides

they are all disaccharides

__________ is always involved in hydrolysis reactions. None of the listed responses is correct. Water ATP H+ and OH- Synthesis

water

Which of the following is a polymer? Triacylglycerol, or fat Testosterone, a steroid hormone Glucose, an energy-rich molecule Fructose, a component of sucrose Cellulose, a plant cell wall component

Cellulose, a plant cell wall component

A shortage of phosphorus in the soil would make it especially difficult for a plant to manufacture __________. cellulose proteins sucrose fatty acids DNA

DNA

Generally, animals cannot digest (hydrolyze) the glycosidic linkages between the glucose molecules in cellulose. How then do cows get enough nutrients from eating grass? The flat teeth and strong stomach of herbivores break the cellulose fibers so that the cows get enough nutrition from the cell contents. They have to eat a lot of it. Microorganisms in their digestive tracts hydrolyze the cellulose to individual glucose units. All of the listed responses are correct. Cows and other herbivores are exceptions and make some cellulose-digesting enzymes.

Microorganisms in their digestive tracts hydrolyze the cellulose to individual glucose units.

The peptide bond is __________. -a covalent bond joining amino acids together to form a polypeptide -a hydrogen bond joining amino acids together to form a polypeptide -a hydrogen bond joining nucleotides together to form a nucleic acid -a covalent bond joining nucleotides together to form a nucleic acid -a covalent bond joining simple sugars together to form a polypeptide

a covalent bond joining amino acids together to form a polypeptide

Sickle-cell anemia is a disease that is caused by __________ in the __________ of the protein. multiple amino acid changes; primary structure an amino acid change in the α subunit; primary structure a single amino acid change; primary structure abnormal hemoglobin; quaternary structure a single amino acid change; secondary structure

a single amino acid change; primary structure

Protein molecules are polymers (chains) of __________. sucrose molecules amino acid molecules DNA molecules fatty acid molecules purines and pyrimidines

amino acid molecules

Sugars have a(n) __________ group that interacts with a _________ group that forms ring structures when the dry molecule is placed in water. carbonyl (-C=O); hydroxyl (-OH) hydroxyl (-OH); hydroxyl (-OH) amino (-NH2); hydroxyl (-OH) carbonyl (-C=O); carboxyl (-COOH) carboxyl (-COOH); hydroxyl (-OH)

carbonyl (-C=O); hydroxyl (-OH)

Which type of protein shields a newly forming protein from cytoplasmic influences while it is folding into its functional form? Enzymes Antibodies Receptor proteins Chaperonins Fibrous proteins

chaperonins

At a conference, the speaker's grand finale was sautéing mealworms (insect larvae) in butter and serving them to the audience. They were crunchy (like popcorn hulls) because their exoskeletons contain the polysaccharide __________. collagen cellulose linoleic acid chitin glycogen

chitin

The molecule with four fused rings that is found in animal membranes and is the precursor of vertebrate sex hormones is __________. testosterone a phospholipid glycerol cholesterol estrogen

cholesterol

When comparing saturated and naturally occurring unsaturated fats, the unsaturated fats have __________ and are __________ at room temperature. trans double bonds; liquids single bonds; solids single bonds; liquids cis double bonds; liquids cis double bonds; solids

cis double bonds; liquids

The type of bond that forms to join monomers (such as sugars and amino acids) into polymers (such as starch and proteins) is a(n) __________ bond. peptide van der Waals covalent ionic hydrogen

covalent

In living organisms, DNA exists as a __________ with the strand(s) __________. double helix; running antiparallel triple helix; as a twisted coil double helix; running parallel single strand; coiled into a helix triple helix; running parallel

double helix; running antiparallel

A polysaccharide that is used for storing energy in human muscle and liver cells is __________. starch glucose chitin cellulose glycogen

glycogen

The sex hormones estrogen, progesterone, and testosterone belong to which class of molecules? Nucleic Acids Amino Acids Proteins Carbohydrates Lipids

lipids

The proper three-dimensional shape and folding of a protein is assisted by _________. molecules called chaperonins escorts a self-assembly process complex nucleic acids complex lipids

molecules called chaperonins

The lipids that form the main structural component of cell membranes are __________. phospholipids cholesterol proteins carbohydrates triacylglycerols

phospholipids

Macromolecules, the molecules of life, include all of the following except __________. proteins carbohydrates trace elements All of the molecules listed are macromolecules. nucleic acids

trace elements

In a dehydration synthesis reaction, __________ is always formed as a by-product of the reaction. H+ and OH- heat ATP water None of the listed responses is correct.

water

Sugars are molecules that have __________ C:H:O and are called __________. a 1:2:1 ratio of; carbohydrates less C and H than O in; lipids equal amounts of; carbohydrates a 2:1:2 ratio of; carbohydrates more C and H than O in; proteins

a 1:2:1 ratio of; carbohydrates

Nitrogenous bases are classified as either purines or pyrimidines. Examples of purines are __________. thymine and cytosine guanine and cytosine adenine and guanine adenine and uracil adenine and thymine

adenine & guanine

Carbohydrates are used in our bodies mainly for __________. energy storage and release structural molecules, such as hair and fingernails lipid storage membrane construction building genetic material

energy storage and release

The tertiary structure of a protein includes all of the following interactions except _________ bonds. peptide ionic hydrophilic disulfide bridge hydrophobic

peptide

The sequence of amino acids in a protein is called the __________ structure of the protein. tertiary None of the listed responses is correct. primary secondary quaternary

primary