Biology Ch3
Biological polymers are often made using dehydration (or condensation) reactions. During these dehydration reactions which of the following occurs (choose all that apply)?
- 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
Which of the following statements about enantiomers are true?
- 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.
The 4 main groups of biological macromolecules are nucleic acids,
- lipids - carbohydrates, complex carbohydrates, or polysaccharides - proteins or polypeptides
Select the characteristics of a hydrolysis reaction.
-A large molecule is broken down into two smaller molecules. -Water is added to the reaction.
At its 3' end, a polynucleotide has a(n)
-OH group
Select all statements that are true about structural isomers.
-They are composed of the same number and type of atoms. -They differ in the actual structure of their carbon skeleton. -They have the same molecular formula.
If a DNA double helix is composed of 20% A, then the percentage of T is
20
When a carbohydrate is formed by linking two monosaccharides by a condensation reaction, we get water plus which of the following?
A disaccharide
is often referred to as the "energy currency of the cell." Please do not spell the entire name of the molecule, use its acronym.
ATP
The two purine bases in DNA are
Adenine Guanine
Which nitrogenous bases are present in RNA?
Adenine Guanine Uracil Cytosine
ATP contains the nitrogenous base ____________, the pentose sugar ribose, and 3 ______________ groups.
Adenine Phosphate
Regarding the chemical nature of nitrogenous bases in DNA, which of the following are correct?
Adenine is a purine Cytosine is a pyrimidine
Which polysaccharides function primarily to store energy?
Amylose Amylopectin Glycogen
In humans, how is glucose transported in the blood?
As a simple monosaccharide
Choose all similarities between starch and cellulose?
Both are found in plants. Both are polysaccharides.
How is information stored in a molecule of DNA?
By varying the sequence of the four types of nucleotides that make up each strand.
Which of the following bonds is essentially nonpolar? C--N C--H C--O O--H N--H
C--H
The framework or backbone of biological molecules consists predominantly of which of the following atoms?
Carbon
Why do hydrocarbons make good fuels?
Carbon-hydrogen bonds store considerable energy.
Which of the following functional groups are polar?
Carboxyl Carbonyl Amino Hydroxyl
From the list below, select all that are polysaccharides.
Cellulose Glycogen Chitin Starch
In a DNA molecule, nitrogenous bases that pair up with each other are said to be which of the following?
Complementary
The genetic code of cells is stored in molecules of
DNA
This molecule stores the genetic information in cells.
DNA
Which of the following molecules have the ability to serve as templates to produce precise copies of themselves?
DNA
In living organisms, molecules of_______ are used to store and transmit the genetic information from one generation to the next, while molecules of _________ use the genetic information to actually assemble proteins.
DNA RNA
Identify the two major classes of nucleic acids.
DNA and RNA
The two classes of nucleic acids are
DNA and RNA
During this type of reaction, a molecule of water is removed.
Dehydration
Which sugar is found in the backbone of DNA molecules?
Deoxyribose
Carbon-oxygen and carbon-nitrogen bonds are described as which of the following?
Formed by an unequal sharing of electrons Polar covalent
A small group of atoms that are attached to larger molecules, providing them with specific chemical properties, is called which of the following?
Functional group
Which of the following are isomers of glucose found in nature?
Glucose Galactose Fructose
What types of bonds keep the two strands of DNA joined to each other?
Hydrogen
A molecule that only contains Blank 1Blank 1 hydrogen , Correct Unavailable and Blank 2Blank 2 carbon , Correct Unavailable is called a hydrocarbon.
Hydrogen carbon
Organic molecules with the same molecular formula may exist in different forms called which of the following?
Isomers
Which of the following statements about carbon are true?
It can form covalent bonds. It forms the framework of biological molecules.
Which of the following statements about carbon are true?
It forms the framework of biological molecules. It can form covalent bonds.
In most plants, how is glucose transported from one part of the plant to another?
It is combined with another monosaccharide to form a disaccharide.
Select the 4 main groups of biological macromolecules.
Lipids Proteins Carbohydrates Nucleic acids
Lactose intolerance is caused by which of the following?
Low levels of the enzyme that digests lactose
The molecules in the given diagram are which of the following (choose all that apply)?
Nitrogenous bases Pyrimidines
C--C and C--H bonds are best described as which of the following?
Nonpolar
What are the three basic components of a nucleotide?
Pentose sugar Phosphate group Nitrogenous base
What type of bond connects adjacent nucleotides in a single strand of a nucleic acid?
Phosphodiester
Which of these bonds is found in a single strand of DNA?
Phosphodiester
A long molecule built by linking together a large number of small, similar molecules termed monomers is which of the following?
Polymer
Which of the following molecules are composed of one or more nucleotides?
RNA ATP NAD+ DNA
Select the main difference between starch & cellulose.
Starch is composed of α-glucose subunits and cellulose is composed of β-glucose subunits.
Glucose and galactose can be described as which of the following?
Stereoisomers
Glucose and fructose can be described as which of the following?
Structural isomers
Hydrocarbons are nonpolar due to which of the following?
The electronegativities of carbon and hydrogen are very similar.
How are the nucleotides in a single polynucleotide chain linked together?
The phosphate group of one nucleotide is covalently linked to the sugar of the next nucleotide.
The sequence of amino acids in a protein is specified by which of the following?
The sequence of nucleotides in a segment of DNA
Which describes purines?
They are found in both DNA and RNA. They are double-ring molecules. They are nitrogenous bases.
Which of the following describes the D and L forms of an organic molecule?
They are mirror images of each other. They are enantiomers. They differ in how they rotate a plane of polarized light.
Choose all statements that describe pyrimidines?
They are nitrogenous bases They include cytosine, thymine, and uracil. They are single-ring molecules.
Which of the following statements best describes hydrocarbons based on their C-C and C-H bonds?
They are nonpolar.
Which of the following describes stereoisomers?
They have the same number and types of atoms. They are identical in terms of which atoms are bonded to each other, but differ in the spatial arrangement of their atoms.
During proper base pairing in DNA, adenine pairs with ____________ and cytosine pairs with ____________. (No abbreviations please).
Thymine Guanine
How are disaccharides formed?
Two monosaccharides are linked together through dehydration synthesis.
Proteins are composed of monomers called ________________, nucleic acids are composed of monomers called ____________________, and carbohydrates are composed of monomers called _________________(for example, glucose).
amino acids nucleotides or nucleotide monosaccharides
A molecule that has mirror-image versions is called a _________________molecule. It is also known as an enantiomer.
chiral
Nitrogenous bases that pair with each other in a DNA molecule are referred to as ___________ BASE-PAIRS
complementary
In order to obtain a stable outer shell of electrons, carbon forms four
covalent bonds
The nucleotides of DNA molecules contain the sugar, __________, as part of the backbone of the molecule.
deoxyribose, deoxy-ribose, or pentose
Transport forms of sugars are commonly made by linking 2 monosaccharides together to form a
disaccharide
A subcategory of stereoisomers that are mirror-images of each other are called
enantiomers
Which of the following are six-carbon sugars?
galactose glucose Fructose
Molecules consisting only of carbon and hydrogen are called
hydrocarbons
In a _______________reaction, water is added to break a specific covalent bond in a macromolecule.
hydrolysis or hydrolytic
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
The main sugar found in milk is the disaccharide
lactose
Polymers are long molecules made of many small, similar units called
monomers
The simplest carbohydrates are
monosaccharides
unique among macromolecules, _____________________ acids are able to serve as templates to produce precise copies of themselves
nucleic
The building blocks of nucleic acids are monomers called
nucleotides
What are the monomers of nucleic acids?
nucleotides
Organisms use sequences of __________ in their DNA to specify the sequences of ____________ ____________ in their proteins.
nucleotides, bases, or nitrogenous base amino acids
Organisms use sequences of ___________ in their DNA to specify the sequences of ___________ ______________in their proteins.
nucleotides, bases, or nitrogenous bases Amino Acids
The 5' end of a nucleotide chain is composed of a(n)
phosphate group.
In nucleic acids, adjacent nucleotides are covalently linked by ______ bonds.
phosphodiester
Long polymers made of monosaccharides that have been linked through dehydration reactions are called
polysaccharides
Match the following polymers with their monomers.
proteins <-> amino acids carbohydrates <-> monosaccharides nucleic acids <-> nucleotides
When a five or six-carbon sugar is dissolved in water, it generally forms which of the following structures?
ring
When a six-carbon sugar is dissolved in water, it generally forms
ring
In cells, DNA serves as a template for the synthesis of ________ , which directs the synthesis of __________.
rna proteins
Information is stored in DNA by varying the __________ of the four types of nitrogenous bases in each strand.
sequence or order
Information is stored in DNA by varying the ________________ of the four types of nitrogenous bases in each strand.
sequence or order
Information is stored in DNA by varying the _______________of the four types of nitrogenous bases in each strand.
sequence or order