The ketone group of D-fructose can form a reversible intramolecular bond with either the hydroxyl group attached at carbon 5 or 6 to form what is known as a
hemiketal
If the intramolecular bond formed for frutose in question 1 connects to the ketone and the hydroxyl group at carbon 5, we form a circular molecule which can be referred to as a
furanose
in protein, what level of structure refers to the three-demensional arrangement of all the atoms in a multiple polypeptide chains.
quarternary
What makes a reducing sugar?
alcohol/ acid?? ask someone
recognize an omega-3 fatty acid, sphingomyelin, steriod, triacylglcerol, and a glycophospholipid
..
What lipids contain fatty acids as part of their structure
all of the above, phospholipids, cerebrosides, DPPC
The titration for M would show
2 platues
should i memorize amino acids again?
Cellulose is connected by which of the following glycosidic bonds?
B- 1,4
The amino acid H plays an important role physiologically in protein structure because
it serves as proton shuttle??
If the pH of a solution is 12, then the concentration of hydrogen ions in that solution
10-12
Whats a membrane lipid composed of sphingosine, fatty acid, and a simple sugar
cerobroside
Premature infants lack palmitoyl phospatidyl cholines (DPPC) are at risk of develop the repiratory distress syndrone, because
DPPC serve as a surfactant to decrease the surface tension of water in alveoli
Which of the following about Positron emission tomography is correct
a radioactive tracer is incorporated into biologically active molecule such as glucose
Whats the number of carbons in fatty acids that are not commonly found in nature?
NOT SURE IF THESE ARE RIGHT CHECK
In addition to phospholipids and cholesterol, this is a major type of membrane lipid.
glycolipid
water is remarkably cohesive as each water molecule can form as many as
4 hydrogen bonds, 2 as a donor and 2 as a acceptor
archaebacteria have modified their lipids to accommodate their environment through
saturated branches
which of the following is/are aqueous compartments enclosed by a lipid bilayer
cytoplasm
Some proteins are anchored to the membrane by being covalently attached to a ------- group by a thioester linkage to a specific cysteine residue
phosphatidate
Which of the followings is the correct order for membrane permeability of different species
H2O>Indole>Tryptophan>glucose> Na+
Which of the following is not a polar amino acid?
P
The pKa of lactic acid is 3.8 and acetic acid is 4.8
acetic acid is a weaker acid
A buffer solution of pH 5.0 has a ration of HA/A- =10. What is the pKa of the acid.
6
A buffer solution
not always has a pH of 7
Which group consists only of amino acids with aromatic side chains
W,F, and Y
Which amino acid contains no chiral atoms
Glycine
Hydrophobic interactions may occur between the R groups of which of the following amino acids.
valine and leucine
This amino acid displays a free amino group in the peptide PHE-LYS-ARG-SER-HIS
PHE
Refer to the following information, what is the predominant form of the amino acid abbreviated D at pH 1?
Positive
The net charge on the amino acid H in a solution at pH 4 is closest to
+1
Which amino acid has an R-group which contains only C and H?
Isoleucine
The net charge on the amino acid K in a solution at pH 6 is closest to
+1
Consider a reaction that produces a significant amount of H+ and is to be carried out at pH 6.1. Would you use a 6.0 pka acid and 7.3 pka amino acid
Acid A (6.0)
What groups are present in A at a pH of 11?
COO- and NH2
The peptide bond
-is usually found in the trans conformation
-does not has free rotation angle of phi and psi
-is shorter than a typical single bond but longer than a double bond
-the six atoms of the peptide bond group at planar.
a-helices are different from B-sheets because
the hydrogen bonds are parallel to axis in a-helices and the hydrogen bonds are perpendicular to axis in B-sheets
Urea denatures the native state of a protein by
interfering with H-bonds
What type of amino acid has the highest melting point, a liquid like or solid one and how do you tell?
a solid one (long with few double bonds)
Tm depends on the GC and AT content of a DNA molecule true or false?
true
Name of molecules that are reducing sugars
Glucose, fructose, galactose
How many chiral carbons are there for glucose in a ring structure.
5
cellulose is indigestible to most animals because
animals do not have the enzymes needed to hydrolyze the beta-glycosidic linkages between the monomer units.
porins are
"inside out" proteins
When the first oxygen binds to Fe in heme of Hb, the Fe is drawn INTO the plane of the porphyrin ring
false
Which of the followings about Fe in heme is correct
the oxidation of ferric ion promotes the superoxide ion production
the second law of thermodynamics states
the total entropy of a system and its surroundings always increases for a spontaneous process
The oligonucleotide pAGGUCCAUUGAA is best described as
an RNA oligonucleotide with 5' phosphate
The fetal hemoglobin has higher affinity to O2 than maternal because
fetus hemoglobin has lower affinity to BPG
The Bohr effect refers to
-more oxygen was released at a lower pH
In a nucleotide, when the nitrogenous base is rotated such that it does not sit over the ribose ring, the base is said to be in what position.
anti
What is the approximate mass of a protein containing 300 amino acids?
33kDa
In general which of the following bonding is the strongest
