Module 2: Biomolecules: DNA, Carbohydrates, Lipids, and Proteins
4 components of amino acid
1. NH3+ 2. H 3. COO- 4. R group
How many nucleotides per turn of B-DNA?
10
There are approximately __________________ bases per turn of a B-DNA double helix.
10
What is the pH of a solution that is a concentration of 3.2 x 10-5 M H+?
4.5
The base sequence of DNA, as written by convention, is in the _______________ direction.
5' to 3'
What is the complementary DNA sequence for 5′-GACTCTTGGTAT-3′? 5′-GACTCTTGGTAT-3′ 5′-CTGAGAACCATA-3′ 5′-ATACCAAGAGTC-3′ 5′-TATGGTTCTCAG-3′ 5′-ATAGGAACAGAG-3′
5′-ATACCAAGAGTC-3′
What is the complementary sequence to 5′-AAGCTTCCGGATATG-3′? 5′-AAGCTTCCGGATATG-3′ 5′-TTCGAAGGCCTATAC-3′ 5′-CATATCCGGAAGCTT-3′ 5′-GTATAGGCCAACGAA-3′ 5′-AAGCTTCCGGATATG-3′
5′-CATATCCGGAAGCTT-3′
What is the H+ concentration in a urine sample that has a pH of 7.2?
6.3 x 10-8 M
Which processes does the Central Dogma rule out? Making RNA or DNA from protein Making protein directly from DNA without an RNA intermediate Making RNA from DNA A and B B and C
A and B
How does a nucleotide differ from a nucleoside? Nucleosides are found in DNA, whereas nucleotides are found in RNA. Only nucleotides contain purines. Nucleosides contain only deoxyribose sugars. A nucleotide is a nucleoside with a phosphate ester linked to the sugar. None of the above
A nucleotide is a nucleoside with a phosphate ester linked to the sugar.
Which of the following statements accurately describe/s properties of prions? Prions cause misfolding of other proteins Prions cause toxic networks of misfolded proteins Prions can be transmitted by ingestion of prion- contaminated food A, B, and C none of the above
A, B, C
What are the normal functions of cholesterol in our bodies? Manage membrane fluidity Synthesize vitamin D Synthesize testosterone and progesterone A and C A, B, and C
A, B, and C
DNA Types:
A, right handed, shorter, dehydrated B, right handed, most DNA, longer Z, left handed
What are the four bases found in DNA?
AGCT
What are the four bases found in RNA?
AGCU
The feature(s) of DNA deduced by Watson and Crick include: two antiparallel polynucleotide chains coiled in a helix around a common axis. that the pyrimidine and purine bases lie on the inside of the helix. that the bases are nearly perpendicular to the axis. All of the above None of the above
All of the above
Describe the relationship between fatty acid chain length, saturation, and the melting point or fluidity of fatty acids.
As the chain length or number of carbon atoms increases, so does the melting point. Shorter chain fatty acids are more prone to be liquid, while longer chain fatty acids are more likely to be solid at room temperature. A saturated fatty acid is one that contains the maximum number of hydrogens attached, with no carbon-carbon double bonds. Unsaturated cis fatty acid chains have the lower melting points due to kinks in the molecules and not packing close together (lower van der waals interactions). Trans unsaturated fats have medium melting points and saturated fats have higher melting points compared to cis unsaturated chains.
The ____________ form of DNA is the predominant form in cells.
B DNA
What amino acids are not found in a-helices? Leucine Proline Glycine A and B B and C
B and C
What are the two essential fatty acids we need to get in our diet? Stearidonic acid or all-cis-6,9,12,15-octadecatetraenoic acid α-Linolenic Acid and ω-3 fatty acid Linoleic Acid and ω-6 fatty acid A and C B and C
B and C
bonds in DNA AND STRENGTH. Base pairs? Base stacking?
Base pairs (hydrogen) < base stacking (ver der waals)
Why are chicken fat, lard, and butter all solids at room temperature while canola oil and olive oil are liquids? Because chicken fat, lard, and butter all come from animal and dairy products. Canola and olive oils have more unsaturated and short chain fatty acids. Chicken fat, lard, and butter have more protein and suspended solids. chicken fat, lard, and butter are fats, not oils chicken fat, lard, and butter have more cholesterol.
Canola and olive oils have more unsaturated and short chain fatty acids.
Cricks three classifications of information transfer in cell: known, special, unknown
Crick proposes three classifications of information transfers, general, special and unknown. General transfers can occur in all cells. -DNA to DNA, DNA to RN RNA to Protein. Special transfers are those that do not occur in most cells, but may occur in special circumstances. -RNA to RNA -RNA to DNA -DNA to Protein. unknown transfers. -Protein to Protein -Protein---DNA -Protein- RNA.
The Central Dogma can be summarized as ___ makes ____ makes ______.
DNA, RNA, protein
Watson Crick Base Pairing DNA? RNA?
DNA: G-C A-T RNA G-C A-U
RNA viruses are an exception to the Central Dogma. True False
False
____________ is a test solution used to identify reducing and nonreducing sugars.
Fehling's
Proteoglycan
Glycoprotein found in cartilage
Mucin
Glycoprotein found in lubrication centers like lungs
Why are some amino acids considered essential amino acids? They are essential to humans' sense of smell. Human cells cannot synthesize them. They require further modification by human cells for protein synthesis. They are used in only a subset of proteins synthesized in human cells. None of the above.
Human cells cannot synthesize them.
Why is the peptide bond planar? Bulky side chains prevent free rotation around the bond. It exhibits partial double-bond character, preventing rotation. Hydrogen bonding between the NH and C=O groups limits movement. None of the above All of the above
It exhibits partial double-bond character, preventing rotation.
____________ are proteins that bind to specific carbohydrate structures.
Lectins
Name two amino acids that are positively charged at a neutral pH. Lysine and arginine Histidine and arginine Cysteine and arginine Lysine and proline Glutamine and histidine
Lysine and arginine
The class of glycoproteins made up of a core protein linked through a serine or threonine to carbohydrates that is made in large amounts in humans infected by the common cold virus is called _________________.
Mucin
Which of the following amino acid residues would most likely be buried in the interior of a water-soluble, globular protein? Aspartate Serine Phenylalanine Lysine Glutamine
Phenylalanine
The charge of an amino group when the pH is one pH unit below the pKa.
Positive
Protein Structure:
Primary: Linear sequence Secondary: Protein folding into alpha helix (no glycine or proline)/beta pleated sheets (glycine and proline) Tertiary: Three dimensional structure Quaternary: 2+ proteins to form a complex subunit
What is the difference between saturated and unsaturated fatty acids? Saturated fatty acids are bound by water whereas unsaturated fatty acids do not bind water. Saturated fatty acids have many double bonds in their hydrocarbon chains whereas unsaturated fatty acids have no double bonds in the hydrocarbon chain. Saturated fatty acids have only single bonds between the carbons in the hydrocarbon chain whereas unsaturated fatty acids have one or more double bonds between carbons in the hydrocarbon chain. Saturated fatty acids are always a solid at room temperature and unsaturated fatty acids normally exist as an oil. Saturated fatty acids are found only in plants and unsaturated fatty acids only in animal fat
Saturated fatty acids have only single bonds between the carbons in the hydrocarbon chain whereas unsaturated fatty acids have one or more double bonds between carbons in the hydrocarbon chain.
_______________ is a simple motif of RNA structure.
Stem loop
The overall structure of an individual protein is referred to as ____________.
Tertiary
What is the Central Dogma Detail
The Central Dogma is a model of information flow in living systems that explains that genetic information flows from DNA to RNA and finally to protein. The process starts with semi-conservative replication of DNA. The genetic information is encoded in the specific sequence of nucleotides in the DNA strand. Next, transcription (DNA→mRNA) occurs and a compliemntary strand of RNA is produced. Finally, translation at ribosomes (mRNA →protein) produce a specific polypeptide sequence that specifies function.
What fat is not a normal part of our diet? Saturated fats Poly-unsaturated fats Omega-3 fatty acids Trans fats, or fats with trans isomers w/double bonds Omega-6 fatty acids
Trans fats, or fats with trans isomers w/double bondsggg
Which has more storage potential? Glycogen or triacylglycerols?
Tria, a few weeks vs 6-12 hours for glycogen
What is the major lipid used for energy storage in our bodies? Triacylglycerides Phosphatidic acid Cholesterol Phosphoglycerides Sphingolipids
Triacylglycerides
Hair can be reshaped into curls or straightened in a process called "perming". One way this is done is by treating hair with a chemical called ammonium thioglycolate, which is a reducing agent, followed by wrapping the the hair around a curler or ironed out straight by flatirons. After the hair has been reshaped it is treated with an oxidizing agent to stabilize the new shape. What amino acids are these chemical treatments affecting and how do they allow hair to be reshaped?
When a solution of ammonium thioglycolate is applied to the hair, the excess ammonia present in the solution helps the hair enlarge so that the reagents can work their way through each strand of hair, enabling it to break open disulfide bridges. For a curly perm, the hair is wound around a curling rod and covered with an oxidizing solution like hydrogen peroxide. The disulfide bonds are reformed with the hair in the new curl formation created by the curling rods. The breaking of the sulfide bridges also create instability and weaken the hair over time.
All fatty acids have these structures in common: a polar carboxylic acid head and charged, polar side chain a polar carboxylic acid head and an uncharged, nonpolar hydrocarbon chain a polar carboxylic acid head and an unsaturated, nonpolar hydrocarbon chain a polar carboxylic acid head and a saturated, nonpolar hydrocarbon chain a polar phosphate head and an uncharged, nonpolar hydrocarbon chain
a polar carboxylic acid head and an uncharged, nonpolar hydrocarbon chain
An example of secondary structure in a protein
alpha helix
According to convention, ____________ is the terminus drawn on the left side of a peptide.
amino
An example of primary structure in a protein
amino acid sequence
____________ is a flat polycylic molecule that is absent in prokaryotic membranes.
cholesterol
The 4 deoxyribonucleoside triphosphates found in the cell are:
dATP, dGTP, dTTP, dCTP
This monosaccharide is found in table sugar:
glucose
____________________ is a branched starch molecule use for storage of glucose in muscle tissue.
glycogen
An example of protein motif
helix turn helix
____________: The type of bond found between an oxygen on one water molecule and hydrogen on a different water molecule
hydrogen
What is the central dogma?
hypothesis proposed by Francis Crick to describe the flow of information from DNA to protein
What are prions? an intracellular organelle used for protein degradation proteins located on virus capsids infectious disease causing proteins cancer specific proteins a self replicating protein
infectious disease causing proteins
Electrostatic interactions between atoms with opposite electrical charges are also called ____________.
ionic bond/salt bridge
____________: Chiral type of amino acids found in proteins.
l amino acids
A nitrogen containing an aromatic base attached to a ribose is a __________________.
nucleoside
IN B DNA the base pairs are ______________ to the helix axis
perpendicular
____________: This amino acid residue disrupts the α helix because its side chain contains a unique ring structure that restricts bond rotations.
proline
This sugar, found in RNA
ribose
_______________: A transient copy of genetic information.
rna
Changes in ____________ create amyloid fibers which are insoluble and are the source of mad cow disease, and Alzheimer's, and Parkinson's diseases.
secondary sctructure
A disaccharide made of the monosaccharides glucose and fructose is:
sucrose
The axis of a double helix can be over-wound by a mechanism called ____________________.
super coiling
____________: The number of hydrogen bonds formed between G and C.
three
DNA is made from the bases adenine, guanine, cytosine, and ____________.
thymine
The configuration of most α-carbon atoms of amino acids linked in a peptide bond is: cis circular parallel trans perpendicular
trans
The transfer of information from DNA to RNA is called ____________.
transcription
The chemical forces that contribute to the stability of the DNA due to the base stacking present in the DNA helix are hydrogen bonds. van der Waals interactions. disulfide bonds. A and C None of the above
van der Waals interactions.
The distance when two atoms no longer repulse each other yet have the strongest attraction is known as the____________ radii or contact distance.
van der waals
____________: Another name for dipolar ions.
zwitterions