CH 5 Macros and DNA (Textbook Q's) Flashcards
When comparing saturated and naturally occurring unsaturated fats, the unsaturated fats have __________ and are __________ at room temperature.
cis double bonds; liquids
If there are no double bonds between carbon atoms composing a chain, then as many hydrogen atoms as possible are bonded to the carbon skeleton. Such a structure is said to be ______ with hydrogen, and the resulting fatty acid is therefore called a _____ fatty acid.
If there are no double bonds between carbon atoms composing a chain, then as many hydrogen atoms as possible are bonded to the carbon skeleton. Such a structure is said to be saturated with hydrogen, and the resulting fatty acid is therefore called a saturated fatty acid.
An ______ fatty acid has one or more double bonds, with one fewer ______ atom on each double-bonded carbon. Nearly all double bonds in naturally occurring fatty acids are _____ double bonds, which cause a kink in the hydrocarbon chain wherever they occur.
An unsaturated fatty acid has one or more double bonds, with one fewer hydrogen atom on each double-bonded carbon. Nearly all double bonds in naturally occurring fatty acids are cis double bonds, which cause a kink in the hydrocarbon chain wherever they occur.
fats with double bonds are
liquids. Un-Saturated
____ double bonds are not naturally occurring fats.
trans double bonds are not naturally occurring fats.
_______ fats have single bonds and are solid at room temperature
saturated fats have single bonds and are solid at room temperature.
fats that have single bonds and are ____ at room temperature are called _____ fats.
fats that have single bonds and are solid at room temperature are called saturated fats.
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.
covalent
Monomers are joined together by a ______reaction in which two molecules are covalently bonded to each other through the _______.
Monomers are joined together by a dehydration reaction in which two molecules are covalently bonded to each other through the loss of a water molecule.
Van der Waals interactions do not link monomers together. They play a role in the______ structure of proteins.
Van der Waals interactions do not link monomers together. They play a role in the tertiary structure of proteins.
A hydrogen bond is a relatively weak bond between polar molecules. An ionic bond cannot form because sugars are not ions.
A hydrogen bond is a relatively weak bond between polar molecules. An ionic bond cannot form because sugars are not ions.
Sugars are molecules that have __________ratio of C:H:O and are called __________.
a 1:2:1 ratio of; carbohydrates
Sugars (Carbohydrates) molecule ratio:
For every one carbon molecule (C), there is one molecule of water (H2O). This means that the ratio of C:H:O is 1:2:1.
The components of nucleic acids are __________.
a nitrogenous base, a pentose sugar, and a phosphate
A nucleotide, in general, is composed of three parts:
A nucleotide, in general, is composed of three parts: a five-carbon sugar (a pentose), a nitrogen-containing (nitrogenous) base, and one or more phosphate groups
In a polynucleotide, each monomer has only one _______ group.
In a polynucleotide, each monomer has only one phosphate group.
the sugar in nucleic acids is a five-carbon sugar called a
the sugar in nucleic acids is a five-carbon sugar called a pentose sugar.
nucleic acid always have a
nucleic acid always have a pentose sugar.
The portion of a nucleotide without any phosphate group is called a
The portion of a nucleotide without any phosphate group is called a nucleoside.
The lipids that form the main structural component of cell membranes are __________.
phospholipids
______ are essential for cells because they make up cell membranes
Phospholipids are essential for cells because they make up cell membranes.
**how form fits function at the molecular level.
Phospholipids have a _____ head and two _____ tails. This permits the phospholipids to be arranged in a bilayer, or double layer, which forms a boundary between the cell and its external environment.
Phospholipids have a hydrophilic head and two hydrophobic tails. This permits the phospholipids to be arranged in a bilayer, or double layer, which forms a boundary between the cell and its external environment.
In living organisms, DNA exists as a __________ with the strand(s) __________.
double helix; running antiparallel
In the DNA molecule, The sugar-phosphate backbones are on the ______ of the helix, and the nitrogenous bases are paired on the _____ of the helix.
The sugar-phosphate backbones are on the outside of the helix, and the nitrogenous bases are paired on the interior of the helix.
In the DNA, the two strands are held together by ____ bonds, The sugar-phosphate backbones are on the_____ of the helix, and the nitrogenous bases are paired on the____ of the helix.
In the DNA, the two strands are held together by hydrogen bonds, The sugar-phosphate backbones are on the outside of the helix, and the nitrogenous bases are paired on the interior of the helix.
The molecule with four fused rings that is found in animal membranes and is the precursor of vertebrate sex hormones is __________.
cholesterol
______ are lipids characterized by a carbon skeleton consisting of four fused rings.
Steroids are lipids characterized by a carbon skeleton consisting of four fused rings. Different steroids are distinguished by the particular chemical groups attached to this ensemble of rings.
______, a type of steroid, is a crucial molecule in animals
Cholesterol, a type of steroid, is a crucial molecule in animals
One characteristic shared by sucrose, lactose, and maltose is that __________.
they are all disaccharides
A _______ is composed of many monosaccharide building blocks.
A polysaccharide is composed of many monosaccharide building blocks.
A _______ is a simple sugar containing three to seven carbons.
A monosaccharide is a simple sugar containing three to seven carbons.
Fructose is a six-carbon ______ sugar
Fructose is a six-carbon monosaccharide sugar
The sequence of amino acids in a protein is called the __________ structure of the protein.
primary
the precise primary structure of a protein is determined by __________. The primary structure in turn dictates secondary and tertiary structures, by means of the chemical nature of the backbone and the side chains (R groups) of the amino acids along the polypeptide.
the precise primary structure of a protein is determined not by the random linking of amino acids, but by inherited genetic information. The primary structure in turn dictates secondary and tertiary structures, by means of the chemical nature of the backbone and the side chains (R groups) of the amino acids along the polypeptide.
Proteins secondary structure is the result of
hydrogen bond formation.
Protein tertiary structure is the result of
tertiary structure is the result of R group interactions.
Protein quaternary structure is the result of
quaternary structure is the result of two or more peptides interacting with each other.
Protein molecules are polymers (chains) of __________.
amino acids molecule
DNA is a polymer of
DNA is a polymer of nucleotides.
Fatty acids are a component of
Fatty acids are a component of triacylglycerols (fats) and phospholipids.
Purines and pyrimidines are nitrogenous bases present in _______, the monomers of _______.
Purines and pyrimidines are nitrogenous bases present in nucleotides, the monomers of nucleic acids.
A protein is a biologically functional molecule that consists of one or more ______, each folded and coiled into a specific________.
A protein is a biologically functional molecule that consists of one or more polypeptides, each folded and coiled into a specific three-dimensional structure.
Diverse as proteins are, they are all unbranched polymers constructed from the same set of ____ amino acids.
20
Polymers of amino acids are called
polypeptides.
Carbohydrates are used in our bodies mainly for __________
energy storage and release
The secondary structure of a peptide backbone is stabilized by __________ forming either a(n) __________ or a(n) __________.
hydrogen bonds; α helix; β pleated sheet
______ bonds stabilize the α helix or β pleated sheet structures of proteins.
hydrogen
_____ bond interactions occur because of R group interactions and give the molecule its tertiary structure.
Ionic
______ are proteins that act as biological catalysts.
Enzymes are proteins that act as biological catalysts.
______ proteins usually function as structural proteins.
Fibrous proteins usually function as structural proteins.
_____ proteins bind signaling molecules such as endorphins that may change the behavior of a cell.
Receptor proteins bind signaling molecules such as endorphins that may change the behavior of a cell.
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)
The components of nucleic acids are __________.
a nitrogenous base, a pentose sugar, and a phosphate
A polysaccharide that is used for storing energy in human muscle and liver cells is __________.
glycogen
a covalent bond joining amino acids together to form a polypeptide
peptide bond
interactions that contribute to the tertiary structure of a protein
“Hydrophobic,” “hydrophilic,” “ionic,” and “disulfide bridge”
are solid at room temperature.
Saturated fats
The subunits (monomers) in cellulose are linked together by __________.
glycosidic linkages
The sequence of amino acids in a protein is called the __________ structure of the protein.
primary
Protein molecules are polymers (chains) of __________.
amino acid molecules
In a hydrolysis reaction, a polymer is __________, and in this process, water is __________.
a polymer is broken up into its constituent monomers; consumed
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.
Covalent bond. Monomers are joined together by a dehydration reaction in which two molecules are covalently bonded to each other through the loss of a water molecule.
In what polysaccharide form do plants store glucose to be available later as an energy source?
starch
The glucose monomers in cellulose are bonded in a ___ glycosidic linkage, whereas those in starch have an __ glycosidic linkage. The enzyme amylase is specific for the __ glycosidic linkage.
The glucose monomers in cellulose are bonded in a β glycosidic linkage, whereas those in starch have an α glycosidic linkage. The enzyme amylase is specific for the α glycosidic linkage.
The subunits (monomers) in cellulose are linked together by __________
glycosidic linkages
Nutritionally, saturated triacylglycerols are considered to be less healthful than unsaturated triacylglycerols. What is the difference between them?
For carbon skeletons of equal length, saturated triacylglycerols have more hydrogen atoms than unsaturated triacylglycerols do.
a droplet of phospholipid molecules is put in water, all the molecules point outward, toward the water. Phospholipids are forced into this orientation because phospholipids have __________.
a charged or polar end and an uncharged or nonpolar end
_____ consist of three (nonpolar) fatty acid tails attached to a glycerol molecule. ______ have two fatty acid tails and a hydrophilic head containing a negatively charged phosphate group.
Triacylglycerols consist of three (nonpolar) fatty acid tails attached to a glycerol molecule. Phospholipids have two fatty acid tails and a hydrophilic head containing a negatively charged phosphate group.
The phrase hydrogenated vegetable oils found on food labels means that unsaturated fats have been synthetically converted to saturated fats by the addition of
hydrogen.
Manufacturers make vegetable oils solid or semisolid at room temperature by __________.
adding hydrogen atoms to the fatty acid hydrocarbon chains, thereby converting carbon-carbon double bonds to single bonds
Some lipids are formed when fatty acids are linked to glycerol. These subunits are linked together by __________linkages.
ester
In making a fat, each of the three fatty acid molecules is bonded to a glycerol molecule by an ____ linkage type of covalent bond.
ester
____ linkages join nucleotides.
Phosphodiester
____ bonds link amino acids.
Peptide
_____ linkages join carbohydrate monomers.
Glycosidic
An ionic bond is
a chemical bond that occurs when electrons are transferred from a metal to a nonmetal, creating oppositely charged ions that attract each other
The overall three-dimensional shape of a single polypeptide is called its __________.
tertiary structure
The tertiary structure is determined by
hydrogen bonds, hydrophobic R groups, ionic bonds between R groups, van der Waals interactions, and disulfide bridges.
_____ breaks the intramolecular bonds, such as hydrogen bonds and van der Waals interactions, that hold the protein in its three-dimensional shape. Without the proper shape, the protein cannot function.
Denaturation
A polypeptide is a chain of amino acids that have been linked together by
dehydration reactions.
The α helix and β pleated sheet represent which level of protein structure?
secondary
Both the α helix and the β pleated sheet are localized regions of polypeptides held in a given structure by hydrogen bonds.
The peptide bond is __________.
a covalent bond (peptide bond) joining amino acids together to form a polypeptide
The “primary structure” of a protein refers to __________.
the sequence of amino acids along a polypeptide chain
______ are the monomers that make nucleic acid polymers, just as glucose is the ________(monomer) from which starch (polymer) is constructed.
Nucleotides are the monomers that make nucleic acid polymers, just as glucose is the monosaccharide (monomer) from which starch (polymer) is constructed.
pyrimidines found in the nucleic acid DNA?
Thymine and cytosine, uracil (in RNA)
Describes a difference between DNA and RNA?
- RNA molecules generally consist of a single polynucleotide chain, whereas DNA molecules generally consist of two polynucleotide chains organized into a double helix.
- Both molecules contain adenine, guanine, and cytosine, but DNA also contains thymine and RNA also contains uracil.
- They contain different sugars.
Each nucleotide consists of three parts: an organic molecule, called a _____ base; a 5-carbon sugar, called a ____; and a ____ group that serves in the ______ covalent bond that forms a bridge between adjacent nucleotides.
Each nucleotide consists of three parts: an organic molecule, called a nitrogenous base; a 5-carbon sugar, called a pentose; and a phosphate group that serves in the phosphodiester covalent bond that forms a bridge between adjacent nucleotides.
Complementary base pairing provides an accurate way to synthesize a new DNA molecule from an existing one and gives RNA molecules particular three-dimensional shapes necessary for their function.
Although the base pairing between two strands of DNA in a DNA molecule can be thousands to millions of base pairs long, base pairing in an RNA molecule is limited to short stretches of nucleotides in the same molecule or between two RNA molecules.
In a hydrolysis reaction, __________, and in this process, water is __________
a polymer is broken up into its constituent monomers; consumed
The meaning of hydrolysis is “_______.”
“to break with water.”
In what polysaccharide form do plants store glucose to be available later as an energy source?
Starch
Strengthens plant cell walls, composed of glucose monomers with B-glycosidic linkages
Cellulose -not digestible by humans
