Chapter Three Chemical Building Blocks of Life Flashcards
Chapter Three
Biological polymers are often made using dehydration (or condensation) reactions. During these dehydration reactions which of the following occurs?
Multiple select question.
An H atom is removed from one molecule and an -OH group is removed from another molecule.
A molecule of water is removed from the reactants.
Two separate molecules are joined together by a covalent bond.
A molecule of water is added to the reactants.
A larger molecule is converted into two smaller molecules.
An H atom is removed from one molecule and an -OH group is removed from another molecule.
A molecule of water is removed from the reactants.
Two separate molecules are joined together by a covalent bond.
Amylopectin
Glycogen
Branched polymer with shorter average chain length and fewer branches
Important storage polymer in animals
Glycogen
Branched polymer with longer average chain length and more branches
Important storage polymer in plants
Unbranched polymer with longer average chain length
Unbranched polymer with shorter average chain length
Branched polymer with shorter average chain length and fewer branches
Important storage polymer in plants
Branched polymer with longer average chain length and more branches
Important storage polymer in animals
Each glucose molecule has seven energy-storing Blank______.
Multiple choice question.
C-H
bonds
O-H
bonds
C-O
bonds
C-C
bonds
C-H bonds
____ is the general term for carbohydrates composed of two monosaccharides.
disaccharides
Select all statements that are true about structural isomers.
Multiple select question.
They have the same molecular formula.
They are composed of the same number and type of atoms.
They are always mirror images of each other.
They differ in the actual structure of their carbon skeleton.
They have the same molecular formula.
They are composed of the same number and type of atoms.
They differ in the actual structure of their carbon skeleton.
A general (all-inclusive) term for organic molecules that have the same molecular formula, but that differ in their structure or in the spatial arrangement of their atoms, is
______
A general (all-inclusive) term for organic molecules that have the same molecular formula, but that differ in their structure or in the spatial arrangement of their atoms, is
isomers
In humans, how is glucose transported in the blood?
Multiple choice question.
Combined with a molecule of fructose to form sucrose
Combined with many other glucose subunits to form a polysaccharide
As a simple monosaccharide
Combined with a molecule of galactose to form lactose
As a simple monosaccharide
The building blocks of nucleic acids are monomers called
___
nucleotides
Choose all statements that describe pyrimidines?
Multiple select question.
They are nitrogenous bases
They include cytosine, thymine, and uracil.
They are found in DNA only.
They are single-ring molecules.
They are single-ring molecules.
They are nitrogenous bases
They include cytosine, thymine, and uracil
Hydrocarbons are nonpolar due to which of the following?
Multiple choice question.
They have localized regions of positive and negative charge.
They are held together entirely by covalent bonds.
They are electrically neutral.
Carbon has a much higher electronegativity than hydrogen.
The electronegativities of carbon and hydrogen are very similar.
The electronegativities of carbon and hydrogen are very similar.
Which of the following statements about enantiomers are true?
Multiple select question.
They have different molecular formulas but the same spatial arrangement of their atoms.
They have the same number of carbon atoms but different carbon skeletons.
They have the same carbon skeleton but differ in how the groups attached to the skeleton are arranged in space.
They are mirror images of each other.
They have the same carbon skeleton but differ in how the groups attached to the skeleton are arranged in space.
They are mirror images of each other.
In most plants, how is glucose transported from one part of the plant to another?
Multiple choice question.
It is combined with several different monosaccharides to form a polysaccharide.
It is combined with many other glucose subunits to form a polysaccharide.
It is transported as a simple monosaccharide.
It is combined with another monosaccharide to form a disaccharide.
It is combined with another monosaccharide to form a disaccharide.
Which describes purines?
Multiple select question.
They are found in both DNA and RNA.
They are nitrogenous bases.
They include adenine and cytosine.
They are single-ring molecules
They are double-ring molecules
They are found in both DNA and RNA.
They are nitrogenous bases.
They are double-ring molecules.
Select all statements that are true about structural isomers.
Multiple select question.
They have the same molecular formula.
They are composed of the same number and type of atoms.
They differ in the actual structure of their carbon skeleton.
They are always mirror images of each other.
They have the same molecular formula.
They are composed of the same number and type of atoms.
They differ in the actual structure of their carbon skeleton.
Small groups of atoms that are attached to larger molecules, giving them specific chemical properties, are called
____
functional groups
A subcategory of stereoisomers that are mirror-images of each other are called
___
enantiomers
Recharge Answer Mode
Fill in the Blank QuestionYour Answer incorrect
Fill in the blank question.
A molecule that has mirror-image versions is called a
____. It is also known as an enantiomer.
chiral
Which of the following are isomers of glucose found in nature?
Multiple select question.
Maltose
Lactose
Fructose
Sucrose
Galactose
Starch
Glucose
Fructose
Galactose
Glucose
The rest are disaccharides
Glucose and galactose are Blank______.
Multiple choice question.
enantiomers
structural isomers
stereoisomers
isotopes
structural isomers
stereoisomers
Which term refers to a small group of atoms that are attached to larger molecules, providing them with specific chemical properties?
Multiple choice question.
Organic group
Isomer
Functional group
Monomer
Functional group
The sequence of amino acids in a protein is specified by which of the following?
Multiple choice question.
The alternating sugar-phosphate groups in the DNA backbone
The sequence of nucleotides in a segment of DNA
Special protein-synthesizing enzymes
The overall 3-dimensional shape of the protein
The sequence of nucleotides in a segment of DNA
Cytosine is a pyrimidine
Thymine is a purine
Guanine is a pyrimidine
Adenine is a purine
Cytosine is a pyrimidine
Adenine is a purine
What type of bond connects adjacent nucleotides in a single strand of a nucleic acid?
Multiple choice question.
Hydrogen
Ionic
Glycosidic
Peptide
Phosphodiester
Phosphodiester
A nucleotide is made of three components: a 5-carbon sugar, a phosphate, and a(n)
_________ ________
nitrogenous base
Choose all statements that describe pyrimidines?
Multiple select question.
They include cytosine, thymine, and uracil.
They are found in DNA only.
They are single-ring molecules.
They are nitrogenous bases
They include cytosine, thymine, and uracil.
They are single-ring molecules.
They are nitrogenous bases
Which of the following describe monosaccharides?
Multiple select question.
Monosaccharides are the simplest carbohydrates.
Monosaccharides are composed of carbon, hydrogen, and oxygen.
All naturally occurring monosaccharides have five or six carbon atoms.
Monosaccharides are the simplest carbohydrates.
Monosaccharides are composed of carbon, hydrogen, and oxygen.
=Long polymers made of monosaccharides that have been linked through dehydration reactions are called
___
polysaccharides
The simplest starch is
____. It is composed of long unbranched chains.
amylose
Select the characteristics of a hydrolysis reaction.
Multiple select question.
A large molecule is broken down into two smaller molecules.
Water is removed in the reaction.
Water is consumed in the reaction.
Two smaller molecules are joined together by an ionic bond.
A large molecule is broken down into two smaller molecules.
Water is consumed in the reaction.
Which monosaccharide is the main component of chitin?
Multiple choice question.
Simple glucose
Fructose
Galactose
N-acetylglucosamine
N-acetylglucosamine
Two main varieties of nucleic acids are
and
DNA and RNA
At its 3’ end, a polynucleotide chain has a(n) Blank______.
Multiple choice question.
phosphate group
nitrogenous base
amino acid
-OH group
-OH group
Organic molecules with the same molecular formula may exist in different forms called which of the following?
Multiple choice question.
Polymers
Isomers
Monomers
Isotopes
Isomers
Which of the following statements about enantiomers are true?
Multiple select question.
They have the same number of carbon atoms but different carbon skeletons.
They are mirror images of each other.
They have the same carbon skeleton but differ in how the groups attached to the skeleton are arranged in space.
They have different molecular formulas but the same spatial arrangement of their atoms.
They are mirror images of each other.
They have the same carbon skeleton but differ in how the groups attached to the skeleton are arranged in space.
Glucose and galactose are Blank______.
Multiple choice question.
structural isomers
enantiomers
stereoisomers
isotopes
stereoisomers
Proteins are composed of monomers called _____
and nucleic acids are composed of monomers called
_____
.
amino acids and nucleotides
Which of the following are disaccharides?
Multiple select question.
Lactose
Galactose
Sucrose
Maltose
Fructose
Glucose
Lactose
Sucrose
Maltose
From the list below, select all that are polysaccharides.
Multiple select question.
Cellulose
Fructose
Starch
Cholesterol
Starch
Cellulose
Triglycerides or triacylglycerols are also known as Blank______.
Multiple choice question.
steroids
fats
sugars
proteins
phospholipids
fats
Of the following list, choose the functions of proteins in living cells.
Multiple select question.
They help the body recognize and destroy foreign microbes and cancer cells.
They are the immediate source of energy for most cell activities.
They catalyze chemical reactions.
They play a key role in moving materials within cells.
They carry genetic information from one generation to the next.
They transport oxygen in the blood of vertebrates
They catalyze chemical reactions.
They play a key role in moving materials within cells.
They help the body recognize and destroy foreign microbes and cancer cells.
They transport oxygen in the blood of vertebrates
The peptide bond Blank______.
Multiple choice question.
is a single bond that can be fully rotated
has a partial double-bond character that prohibits rotation
is a unique double bond that allows partial rotation
has a partial double-bond character that prohibits rotation
Which of the following are common steroids?
Multiple select question.
Cholesterol
Triglycerides
Estrogen
Testosterone
Phospholipids
Estrogen
Testosterone
Cholesterol
Which of the following are lipids?
Multiple select question.
Fats
Starch and glycogen
Nucleotides
Steroids
Steroids and Fats
Which group of molecules forms the core of all biological membranes?
Multiple choice question.
Steroids
Polynucleotides
Polysaccharides
Phospholipids
Fats
Phospholipids
pWhich of the following describes the structure of a phospholipid?
Multiple choice question.
A nonpolar head and two long, polar tails
Two polar heads and a long nonpolar tail
A polar head and two long, nonpolar tails
Two nonpolar heads and a long polar tail
A polar head and two long, nonpolar tails
There are 20 different amino acids that commonly occur in proteins. Humans cannot synthesize some of those amino acids and must get them from their diets. How many such essential amino acids are there?
Multiple choice question.
3
8
12
15
8
Which of the following is an accurate description of a triglyceride?
Multiple choice question.
A three-carbon chain where each carbon is bound to a hydroxyl group
Three glycerol molecules joined to one fatty acid
A hydrocarbon chain bound to 3 carboxyl groups
One glycerol molecule joined to three fatty acids
One glycerol molecule joined to three fatty acids
When two amino acids are linked together, a peptide bond is formed between the
_____ group of one and the
_____ group of the other. Please only fill blanks with the names of the groups without specifying which atom they are attached to.
amino, carboxyl
Alpha helices create regions of the protein that are
_____ while beta sheets create regions that are
____
cylindrical, planar
The covalent bond that joins two amino acids is called a(n)
____ bond
peptide
a ___ ___ consists of a long chain hydrocarbon with a carboxyl group
fatty acid
A double bond has a
__ when the carbon chain is on the opposite side before and after the double bond.
trans
The structure of a phospholipid can best be described as which of the following?
Multiple choice question.
Glycerol joined to 3 fatty acids and a phosphate group
A 5-carbon sugar joined to a nitrogenous base and a phosphate group
Five interlocking carbon rings joined to a phosphate group
A 5-carbon sugar joined to a nitrogenous base and 2 phosphate groups
Glycerol joined to 2 fatty acids and a phosphate group
Glycerol joined to 2 fatty acids and a phosphate group
Keratin, fibrin, and collagen are all proteins that function in Blank______.
Multiple choice question.
storage
transport
muscle contraction
support
support
A protein’s final structure can include which of the following?
Multiple choice question.
Regions shaped like an α-helix and regions shaped like a β-pleated sheet.
Regions shaped like a β-pleated sheet only
Regions shaped like an α-helix only
Reason: A protein may contain some regions shaped like an α-helix and some regions shaped like a β-pleated sheet.
Regions shaped like an α-helix and regions shaped like a β-pleated sheet.
Select the characteristics of chaperone proteins.
Multiple select question.
They have been found in virtually every organism that has been examined.
They are not required for viability.
They are used both to accomplish the original folding of proteins and to restore the structure of incorrectly folded proteins.
Cells increase the production of many chaperone proteins when they are exposed to high temperatures.
They are used both to accomplish the original folding of proteins and to restore the structure of incorrectly folded proteins.
Cells increase the production of many chaperone proteins when they are exposed to high temperatures.
They have been found in virtually every organism that has been examined.
The 20 common amino acid are classified into five chemical classes based on which of the following?
Multiple choice question.
Their carboxyl groups
The number of peptide bonds they form
Their amino groups
Their central carbon atom
Their R groups
Their R groups
Which statement accurately describes amino acids in living things?
Multiple choice question.
A cell typically has about 50% l-amino acids and 50% d-amino acids.
Proteins contain l-amino acids and d-amino acids are generally very rare.
Proteins contain d-amino acids and l-amino acids are never found in living cells.
Proteins contain l-amino acids and d-amino acids are never found in living cells.
Proteins contain l-amino acids and d-amino acids are generally very rare.
During protein synthesis, amino acids are linked together using a
___. As a result, a covalent bond is formed.
dehydration
Where are the peptide bonds located in a polypeptide?
Multiple choice question.
Between the R groups of 2 different amino acids in the polypeptide chain
incorrect
Between the amino group of one amino acid and the carboxyl group of another
At the N-terminus of the polypeptide chain
Between 2 adjacent polypeptides
Between the amino groups of 2 different amino acids in the polypeptide chain
Between the amino group of one amino acid and the carboxyl group of another
Which of the following accurately describes the chemical structure of a typical amino acid found in a protein?
Multiple choice question.
A central carbon is bound to a carbonyl group, an amino group, and two R groups.
A central carbon atom is bound to an amino group, carboxyl group, a side chain, and a hydrogen atom.
A central carbon is double bonded to both an amino group and a carboxyl group.
Reason: Carbons in amino acids are not double bonded, the central carbon forms four bonds.
A central carbon atom is bound to an amino group, carboxyl group, a side chain, and a hydrogen atom.
What type of reaction is responsible for linking amino acids together to form polypeptides?
Multiple choice question.
Polymerization synthesis
Dehydration synthesis
Peptide synthesis
Reason: Peptide bonds are formed by dehydration synthesis.
Hydrolysis
Dehydration
Why do cells increase the production of many chaperone proteins when they are exposed to high temperatures?
Multiple choice question.
Heat provides the energy needed for chaperone proteins to function correctly.
Heat provides the energy needed to synthesize chaperone proteins.
High temperatures cause proteins to unfold and more chaperones are needed to help them refold correctly.
As temperature increases, new proteins are manufactured at a faster rate and more chaperones are needed to help them fold correctly.
High temperatures cause proteins to unfold and more chaperones are needed to help them refold correctly.
Each kind of protein has a unique sequence of
_____ ____________
amino acids
In general, where are nonpolar and polar amino acids found in a folded protein?
Multiple choice question.
Non-polar - interior; polar - exterior
correct
Non-polar - C-terminus; polar - N-terminus
Non-polar - exterior; polar - interior
Non-polar - N-terminus; polar - C-terminus
Non-polar - interior; polar - exterior
Which type of interaction involves the formation of a covalent bond between two different amino acid side chains?
Multiple choice question.
Hydrophobic exclusion
Hydrogen bond
Van der Waals attraction
Ionic bond
Disulfide bridge
Disulfide bridge
Individual polypeptides within a protein are referred to as which of the following?
Multiple choice question.
Amino acids
Motifs
Monomers
Subunits
Subunits
In cells of E. coli, a special class of chaperone proteins, called
_____ associate to form a large cylinder-shape container that can refold improperly folded proteins.
chaperonins
You are studying a protein and notice that it contains two regions made of beta-sheets connected by an alpha-helix. This type of recurring structure that can be found in proteins with very different functions is called a Blank______.
Multiple choice question.
conserved structure
primary structure
motif
domain
motif
If the interactions that maintain the 3-dimensional shape of a protein are disrupted so that the polypeptide chains completely unfold, how is this protein described?
Multiple choice question.
It is unpolymerized.
It is denatured.
It is linearized.
It is polymerized.
It is ionized.
It is denatured.
Protein denaturation may be caused by an increase in which of the following?
Multiple select question.
Temperature
The concentration of chaperone proteins
pH
Ionic concentration
pH
Ionic concentration
