chapter 3 - molecules of life
A carbohydrate is a macromolecule that contains carbon, hydrogen, and oxygen in what ratio?
1:2:1
What is a true statement about base pairings in a DNA molecule.
A always pairs with T and G always pairs with C.
Nucleic acids encode information in their sequence of nucleotides, represented by the letters A, T, G, C, and U. What set of nucleotides is used in DNA?
A, T, C, G
Nucleic acids encode information in their sequence of nucleotides, represented by the letters A, T, G, C, and U. What set of nucleotides is used in RNA?
A, U, G, C
How may a chaperone protein deficiency play a role in Alzheimer's disease?
By failing to facilitate protein folding, amyloid protein clumping in the brain cells may occur.
Which of the following correctly describes the role of chaperone proteins?
Chaperone proteins help new proteins fold correctly.
What are the examples of transmissible spongiform encephalopathies (TSEs)
Creutzfeldt-Jacob disease in humans, mad cow disease in cattle, kuru, scrapie in sheep
What are the disorders that may result from a chaperone protein deficiency.
Creutzfeldt-Jacob disease, Alzheimer's disease, Mad cow disease
What are the ways that DNA differs from RNA.
DNA is a double strand of complementary nucleotides, DNA uses deoxyribose sugar, and uses thymine as a base.
How do enzymes aid the process of dehydration synthesis?
Enzymes facilitate the positioning of the molecules so that the correct chemical bonds are stressed and broken.
What has happened to the protein in the diagram?
It has become denatured.
If a nucleic acid uses uracil as a nucleotide, then you would know that it is ______. If a nucleic acid uses thymine as a nucleotide, then you would know that it is ______.
RNA; DNA
What does it mean when an enzyme becomes denatured?
The enzyme changes shape due to environmental conditions and so can no longer function.
What is the importance of the four levels of protein structure?
The structure of a protein is very important because it determines the protein's function.
What are the reasons why A and T do not pair with either C or G in a DNA molecule.
Two little bases cannot pair together without distorting the helix, Two big bases cannot pair together without distorting the helix, The pairings could not form proper hydrogen bonds.
In DNA, the base __________ always pairs with the base thymine, and the base cytosine always pairs with the base __________.
adenine; guanine
A protein is composed of a long chain of monomers called _______________ acids.
amino
Peptide bonds are formed when ______ acids are joined together in the synthesis of a protein.
amino
The monomer present in proteins is a(n) _____, whereas the monomer present in lipids is a(n) _____.
amino acid; fatty acid
A single carbon atom bonded to a hydrogen atom, an R group, a carboxyl group, and amino group forms the basic structure of ______.
amino acids
What monomer makes up proteins?
amino acids
proteins
amino acids
Organic molecules, such as proteins and carbohydrates, consist of a ______-based core with special groups attached.
carbon
What elements must be present in a carbohydrate molecule?
carbon, hydrogen, and oxygen
A fatty acid contains a ______ and a ______.
carboxyl group & hydrocarbon
Cows and horses can digest the polysaccharide ____________ that is present in the cell walls of plants because cows and horses harbor microbes with specific enzymes necessary to break down that polysaccharide.
cellulose
What structural polysaccharide in plants can only be digested by some organisms that possess special enzymes?
cellulose
What is the term that describes the special proteins that help a protein fold correctly?
chaperone proteins
What steroids are a type of lipid.
cholesterol, estradiol, testosterone
Which of the following that are lipids.
cholesterol, phospholipids, waxes, steroids
The white blood cells shown in the image can make ______ proteins that attack invaders.
defensive
During a ____________ , reaction a hydrogen is removed from one molecule and a hydroxyl group from another molecule, together the two form water.
dehydration
When a hydroxyl group (OH) is removed from one monomer and a hydrogen (H) is removed from another monomer, forming a covalent bond between the two monomers, the process is called ______ synthesis.
dehydration
When a protein changes shape it can no longer function and is said to be
denatured
What is a simple carbohydrate that is composed of two monosaccharides linked together?
disaccharide
What are the types of proteins?
enzymes ,transport proteins ,structural proteins, contractile proteins, defensive proteins
A long chain of carbon and hydrogen atoms ending in a carboxyl group is a(n) ______.
fatty acid
lipids
fatty acids
What is true about plant fats called oils.
fatty acids contain double bonds, unsaturated, liquid at room temperature
A nucleotide is composed of
five-carbon sugar, phosphate group, an organic nitrogen base
Cholesterol is a lipid composed of ______.
four carbon rings
Special groups that are attached to organic molecules and that have specific chemical properties are called _____ groups.
functional
The polysaccharides glycogen, cellulose, and starch are complex carbohydrates composed of ______ monomers.
glucose
The two nitrogenous bases that form the rungs of the double helix in DNA are connected to one another by ___________ bonds
hydrogen
Trans fats can be produced by industrially adding ______ to unsaturated fats.
hydrogen
What are the components of an amino acid?
hydrogen atom, functional group, carboxyl group, central carbon atom, amino group
The secondary structure of a protein is determined by ______.
hydrogen bonds that form between different parts of the polypeptide causing it to fold
A polymer can be broken down when a water molecule comes in and breaks the covalent bond between monomers in a process called ______.
hydrolysis
What are the principal functional groups called?
hydroxyl, phosphate, amino, carbonyl, carboxyl
Fats are ______ molecules composed of ______ acids bound to a glycerol backbone.
lipid; fatty
________________ are macromolecules that contain many C-H bonds for long-term energy storage and are nonpolar and therefore insoluble in water.
lipids
What are the factors that can cause a protein to become denatured.
lowering the pH, and increasing the temperature
Large organic molecules such as proteins, lipids, carbohydrates, and nucleic acids are collectively called ______.
macromolecules
Saturated fats differ from unsaturated fats because saturated fats have the ______ number of hydrogen atoms and no ______ bonds between carbon atoms.
maximum; double
What is the sequence of how a chaperone protein works?
misfolded protein enters inside the chaperone, visiting protein is induced to unfold and refold again before it leaves, polypeptide chain has then refolded into a different shape, and correctly folded protein leaves the chaperone
Macromolecules are made of smaller units called ______.
monomers
Polymers are built of smaller subunit molecules known as ______.
monomers
The subunits of macromolecules like proteins, carbohydrates, and nucleic acids are called ______.
monomers
What statement is true about the relationship between monomers and polymers?
monomers are small subunits of polymers
A type of carbohydrate called a simple sugar is composed of one subunit and is called a ______.
monosaccharide
carbohydrates
monosaccharides
Nucleotides are the monomers that make up ______.
nucleic acids
Which of the main macromolecules are responsible for storing genetic information?
nucleic acids
What are the four main types of macromolecules found in organisms?
nucleic acids, proteins, lipids, carbohydrates
Carbon-based molecules that are formed by living organisms and that have special groups attached are referred to as ______ molecules.
organic
The type of covalent bond that links amino acids together in a protein is called a(n) ______ bond.
peptide
Phospholipids consist of a polar head made of a ______________ group and two nonpolar fatty acid tails.
phosphate
What special type of lipid forms layers called membranes that surround cells and cell compartments?
phospholipids
________________ are triglycerides that contain a phosphate group rather than a third fatty acid, giving it a polar head and two nonpolar tails.
phospholipids
Starch and cellulose are polysaccharides found in __________, while glycogen and chitin are polysaccharides found in ________________ and fungi
plants; animals
Nucleic acids consist of long ______ chains.
polynucleotide
Another word for a protein made of a long chain of amino acids connected to one another by peptide bonds is
polypeptide
The quaternary structure of a protein forms when two or more ______ chains associate together.
polypeptide
Carbohydrates that are the most complex because they are composed of chains of simple sugars are called ______.
polysaccharides
The sequence of the amino acids in a polypeptide chain is called the ______ structure of a protein.
primary
An infectious protein that is presumed to be the cause of many transmissible spongiform encephalopathies (TSEs) is called a
prion
The three-dimensional shape of a(n) ______ determines its specific function.
protein
Enzymes are generally ______ that speed up chemical reactions by positioning the molecules so they can be stressed and broken.
proteins
Functional polypeptides are more commonly called
proteins
What type of macromolecule functions in structural support, transport of materials, defense of the organism, and as enzymes in chemical reactions?
proteins
When a protein is composed of more than one polypeptide chain, it is referred to as having a ______ structure.
quaternary
Alpha helices and beta pleated sheets are examples of the ______ structure of a protein.
secondary
RNA consists of a ______ strand of nucleotides, and DNA consists of a ______ strand of nucleotides.
single; double
Synthetic testosterone is known as an anabolic
steroid
In cells, macromolecules called nucleic acids ______.
store genetic information
A disaccharide is a type of simple carbohydrate composed of two simple
sugars
The three-dimensional structure of a single polypeptide chain as determined by polarity of amino acids is called the ______ structure of a protein.
tertiary
A triglyceride is a molecule that contains
three fatty acids and a glycerol molecule.
What directly and primarily determines how a protein functions?
three-dimensional shape
Hydrogenation, a process of adding hydrogens to unsaturated fats produces ______, which can extend the shelf life of a product containing these types of fats.
trans fats
The red blood cells shown in the image contain a ______ protein
transport
At room temperature, ______ fats are liquid, while ______ fats are solid.
unsaturated; saturated
Hydrolysis is the process of adding _______________, to a polymer causing it to break into smaller subunits.
water
In dehydration synthesis, monomers are linked with a covalent bond to build macromolecules, and a molecule of ______ is removed.
water
