BIOL 1100 ch. 3
Identify the functional groups. DNA and RNA are functional groups. Amino and carboxyl are functional groups. Lipids and proteins are functional groups.
amino and carboxyl are functional groups
A function of cholesterol that does not harm health is its role _____. the most abundant male sex hormone All of cholesterol's effects cause the body harm. in calcium and phosphate metabolism as the primary female sex hormone as a component of animal cell membranes
as a component of animal cell membranes
The structure in the figure is HOC with another O attached to the carbon by double bond. This carbon is attached to CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH3. Which of the following statements regarding the molecule illustrated in the figure is true? Molecules of this type are usually liquid at room temperature. It is an entirely nonpolar molecule. It would be highly soluble in water. It is a saturated fatty acid.
it is a saturated fatty acid
A molecule with the chemical formula C6H12O6 is probably a glycerol. lipid. hydrocarbon. monosaccharide
monosaccharide
Part complete What do fats, steroids, and waxes have in common? (a) Moderate polarity. (b) Low solubility in water. (c) They occur in membranes. Both (a) and (c). Both (b) and (c).
(b) low solubility in water
important info
. A monosaccharide cannot be hydrolyzed any further. 2. Lactose, the sugar in milk, is a disaccharide, because it can be split into two monosaccharides. 3. A carbohydrate that yields many monosaccharides when hydrolyzed is a polysaccharide . 4. A simple sugar is composed of equal parts carbon and water, which gave rise to the general name of any sugar as a carbohydrate .
There are 5 functional groups in the figure. Group A is OH, group B is CO where oxygen is attached to carbon by double bond, group C is COOH where the first oxygen is attached to the carbon by double bond and the second oxygen is attached to the carbon by single bond , group D is NH2, group E is SH. Which functional group shown in the figure is characteristic of alcohols? A B C D E
A
Select the statement that is incorrect. View Available Hint(s) Complex sugars are carbohydrates. All carbohydrates have the general formula Cn(H2O)n. Simple sugars are carbohydrates. Simple sugars contain only carbon, oxygen, and hydrogen atoms.
All carbohydrates have the general formula Cn(H2O)n.
Which of the following hydrocarbons has a double bond in its carbon skeleton? C2H2 C2H6 C2H4 C3H8
C2H4
There are five structures in the figure: structure A is CH3NH2, structure B is CH3SH, structure C is CH3CH2COH where the oxygen is attached to carbon by double bond, structure D is CH3OP with one oxygen attached to phosphorus by double bond and 2 oxygen atoms attached to phosphorus by single bond, both with a charge of 1 minus; structure E is H3CCH2OH. Which molecule shown in the figure contains a functional group that cells use to transfer energy between organic molecules? A B C D E
D
There are five structures in the figure: structure A is H2NOH, structure B is CH4, structure C is CH3CHOH where oxygen is attached to the second carbon by double bond and the hydrogen is attached to the oxygen, structure D is H2CO where oxygen is attached to carbon by double bond, structure E is H2CCHOH where 2 carbons are attached by double bond. Which of the structures illustrated in the figure contain(s) a carbonyl functional group? A C and D C D C and E
D
important
Nucleic acid polymers are made up of nucleotide monomers. Carbohydrate polymers are made up of simple sugar monomers. Protein polymers are made up of amino acid monomers.
The figure shows four types of the protein structure: primary, secondary, tertiary, and quaternary. These figures show the four levels of protein structure: primary, secondary, tertiary, and quaternary structure. Which level of protein structure is characteristic of some, but not all, proteins? Tertiary level of protein structure Quaternary level of protein structure Secondary level of protein structure
Quaternary level of protein structure
Which of these is NOT a lipid? steroids phospholipid RNA wax cholesterol
RNA
Testosterone and estradiol are male and female sex hormones, respectively, in many vertebrates. How do these molecules differ from each other? Testosterone and estradiol are structural isomers but have the same molecular formula. Testosterone and estradiol are enantiomers of the same organic molecule. Testosterone and estradiol have different functional groups attached to the same carbon skeleton. Testosterone and estradiol are cis-trans isomers but have the same molecular formula.
Testosterone and estradiol have different functional groups attached to the same carbon skeleton.
Part complete What could happen if a mutation in a gene caused a hydrophobic amino acid in a polypeptide to be replaced by a hydrophilic amino acid? The shape of the protein would not be affected if only one amino acid in the primary structure is changed. The new amino acid would not form the same interactions with hydrophobic R groups, and the protein's shape would likely be affected. There would be no effect as long as the protein had quaternary structure, because primary structure does not affect that level. The hydrophilic amino acid could not form the proper peptide bond in its new location, so both the shape and function of the protein would be affected.
The new amino acid would not form the same interactions with hydrophobic R groups, and the protein's shape would likely be affected.
Your body contains tens of thousands of different proteins, each with a specific structure and function. The unique three-dimensional shape of each of these diverse proteins is based on several superimposed levels of structure. Which of the following statements is an accurate description of proteins? The primary structure of a protein is the order of amino acids in a polypeptide, as coded for in the DNA of a gene. The 20 amino acids found in proteins differ in the composition of their R groups, which may be either polar or charged. Secondary structures, which include the alpha helix or beta pleated sheet, are held together by interactions between R groups. Tertiary structure is the overall shape of a polypeptide, which may be stabilized by hydrophobic interactions, hydrogen bonds, ionic bonds, and peptide bonds. Quaternary structure is only found in proteins that have four identical polypeptide subunits.
The primary structure of a protein is the order of amino acids in a polypeptide, as coded for in the DNA of a gene.
Part complete Why are the vertebrate sex hormones estradiol and testosterone considered to be lipids? Their carbon skeletons are composed of primarily C-C and C-H bonds. They are essential components of cell membranes. They are made of fatty acids. They are hydrophilic compounds.
Their carbon skeletons are composed of primarily C-C and C-H bonds.
Which of the following statements concerning saturated fats is true? They are generally solid at room temperature. They contain fewer hydrogen atoms than unsaturated fats having the same number of carbon atoms. They are more common in plants than in animals. They have multiple double bonds in the carbon chains of their fatty acids.
They are generally solid at room temperature.
Which of the following is true regarding saturated fatty acids? They are the predominant fatty acid in corn oil. They are the principal molecules in lard and butter. They are usually produced by plants. They have double bonds between the carbon atoms of the fatty acids. They are usually liquid at room temperature.
They are the principal molecules in lard and butter.
Proteins are polymers of _____. CH2O units nucleotides glycerol amino acids hydrocarbons
amino acids
Which of the following statements concerning unsaturated fats is true? They contain more hydrogen than do saturated fats having the same number of carbon atoms. They are more common in animals than in plants. They generally solidify at room temperature. They have double bonds in their fatty acid chains.
They have double bonds in their fatty acid chains.
Part complete Identify the level(s) of protein structure present in this molecule. Four subunit polypeptides arranged into a functional molecule. Select all that apply. primary secondary tertiary quaternary
all of them
Changing a single amino acid in a protein consisting of 433 amino acids would always alter the primary structure of the protein and sometimes alter its tertiary structure or function. always alter the primary and tertiary structure of the protein but never alter its function. always alter the primary structure of the protein but never alter its tertiary structure or function. sometimes alter the primary and tertiary structure of the protein but always alter its function.
always alter the primary structure of the protein and sometimes alter its tertiary structure or function.
The structure in the figure is H2NCHCNHCHCOH where R-radicals are attached to the first and the third carbons, oxygens attached to the second and to the fourth carbons by double bonds. Bond A is between the first nitrogen and the first carbon. Bond B is between the first carbon and the second carbon. Bond C is between the second carbon and the second nitrogen. Bond D is between the second nitrogen and the third carbon. Bond E is between the third carbon and the fourth carbon. At which bond in the figure would water need to be added to achieve hydrolysis of the dipeptide, back to its component amino acids? A B C D E
c
The large diversity of shapes of biological molecules is possible because of the extensive presence of _____ in the molecules. View Available Hint(s) carbon hydrogen sulfur nitrogen oxygen
carbon
Palm oil and coconut oil are more like animal fats than are other plant oils. Because they __________ than other plant oils, they may contribute to cardiovascular disease. View Available Hint(s) contain more sodium contain more double bonds are less soluble in water contain less hydrogen contain fewer double bonds
contain fewer double bonds
What is another name for a condensation reaction? monomerization water formation catabolism dehydration hydrolysis
dehydration
There are 20 different amino acids. What makes one amino acid different from another? different side chains (R groups) attached to an α carbon different side chains (R groups) attached to the amino groups different side chains (R groups) attached to the carboxyl carbon different asymmetric carbons
different side chains (R groups) attached to an α carbon
Which of the following chemical equations describes a hydrolysis reaction? monosaccharide + monosaccharide + H2O → disaccharide monosaccharide + monosaccharide → disaccharide + H2O disaccharide → monosaccharide + monosaccharide + H2O disaccharide + H2O → monosaccharide + monosaccharide
disaccharide + H2O → monosaccharide + monosaccharide
Sucrose is formed when glucose is joined to fructose by a(n) __________. View Available Hint(s) ester linkage phosphodiester linkage ionic bond glycosidic linkage peptide linkage
glycosidic linkage
Humans can digest starch but not cellulose because humans have enzymes that can hydrolyze the β glycosidic linkages of starch but not the α glycosidic linkages of cellulose. the monomer of starch is glucose, whereas the monomer of cellulose is glucose modified by the addition of a nitrogen-containing group. humans harbor starch-digesting bacteria in the digestive tract, but not cellulose-digesting bacteria. humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.
humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.
Most organic compounds contain carbon and _____. View Available Hint(s) nitrogen sulfur phosphate hydrogen oxygen
hydrogen
The secondary structure of a protein results from _____. hydrophobic interactions hydrogen bonds bonds between sulfur atoms peptide bonds ionic bonds
hydrogen bonds
What is the name of the process during which a bond between two monomers is broken? condensation hydrolysis dehydration combustion
hydrolysis
The characteristic that all lipids have in common is that __________. View Available Hint(s) they do not have a high energy content they are all acidic when mixed with water they are all made of fatty acids and glycerol none of them dissolves in water they all contain nitrogen
none of them dissolves in water
Which of these is rich in unsaturated fats? beef fat butter olive oil lard a fat that is solid at room temperature
olive oil
What type of bond joins the monomers in a protein's primary structure? ionic peptide S - S hydrogen hydrophobic
peptide
Tertiary structure is NOT directly dependent on _____. peptide bonds hydrogen bonds hydrophobic interactions ionic bonds bonds between sulfur atoms
peptide bonds
h bonds maintain the primary structure of a protein? hydrogen bonds peptide bonds ionic bonds disulfide bonds
peptide bonds
The four main categories of large biological molecules present in living systems are __________. View Available Hint(s) proteins, DNA, RNA, and steroids nucleic acids, carbohydrates, monosaccharides, and proteins monosaccharides, lipids, polysaccharides, and proteins proteins, nucleic acids, polysaccharides, and lipids RNA, DNA, proteins, and carbohydrates
proteins, nucleic acids, polysaccharides, and lipids
This figure is an example of a(n) _____. The figure shows an organic compound, which consists of a glycerol molecule and three fatty acids attached to it. These fatty acids have no double bond. steroid saturated fat protein nucleic acid unsaturated fat
saturated fat
The α helix and β pleated sheet are examples of which level of protein structure? primary secondary tertiary quaternary primary, secondary, tertiary, and quaternary
secondary
Some regions of a polypeptide may coil or fold back on themselves. This is called __________, and the coils or folds are held in place by __________. View Available Hint(s) tertiary structure ... hydrogen bonds secondary structure ... peptide bonds primary structure ... covalent bonds secondary structure ... hydrogen bonds tertiary structure ... covalent bonds
secondary structure....covalent bonds
The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are the α form. Which of the following could amylase break down? chitin starch starch and chitin cellulose
starch
Which functional group is NOT present in this molecule? COOHCHNH2, with an -CH2OH group attached to the 2nd carbon atom. sulfhydryl carboxyl amino hydroxyl
sulfhydryl
Interactions between the side chains (R groups) in a polypeptide are most important in stabilizing which of the following? primary structure quaternary structure secondary structure tertiary structure
tertiary structure
Which feature of large biological molecules explains their great diversity? The many classes of large biological molecules The diversity of elements found in large biological molecules The many ways that monomers of each class of biological molecule can be combined into polymers
the many ways that monomers of each class of biological molecule can be combined into polymers
Lactase is an enzyme composed of a single polypeptide that hydrolyzes the disaccharide lactose to produce monosaccharides. The optimal pH for lactase activity is 6. Transfer of lactase to pH 5 results in a substantial decrease in enzyme activity, likely due to the disruption of the primary and secondary structure of the enzyme. the secondary and tertiary structure of the enzyme. the secondary, tertiary, and quaternary structure of the enzyme. only the primary structure of the enzyme
the secondary and tertiary structure of the enzyme
A dehydration reaction (or condensation reaction) is the process in which __________. View Available Hint(s) water molecules are produced as a polymer is formed from monomers water molecules are used as a source of raw material to break down polymers to monomers water molecules are attracted to each other the bonds between the individual monomers of a polymer are broken by the addition of water molecules None of the listed choices is correct.
water molecules are produced as a polymer is formed from monomers
Dr. Haxton told one of his students, "To move in the bloodstream, fats need the help of phospholipids." What would a good student say? Right. Fats are too polar to travel alone in water. You have it backwards. Fats help phospholipids to travel. Sorry, Dr. Haxton! Help comes from cholesterol, not phospholipids. Not so. Fats are small enough to travel easily without help. Yes. Nonpolar molecules aren't compatible with water.
yes. nonpolar molecules arent compatible with water