1.How many water molecules are lost from the condensation
of 100 amino acids into a polypeptide?
2.Amino acids are connected via __________ bonds, which
occur between the carboxyl group of one amino acid and the
amino group of another.
3 . In how many different ways can the amino acids leucine,
glutamate, and glycine be arranged?
4 .A new drug is developed which selectively cleaves covalent
bonds between two sulfur atoms of non-adjacent amino acids
in a polypeptide chain. Which level of protein structure in
affected molecules would be most directly affected by the
drug?
5.Albumin is a large protein which circulates freely in human plasma. Another
type of protein, called aquaporins, act as a channel for water to enter and exit a
cell, and are located within the lipid bilayer of a cell’s plasma membrane. Based
on their physiological locations, how would the tertiary structure of these two
proteins mostly likely compare?
a. Albumin has more of nonpolar core with nonpolar out layer while
aquaporins have a more polar core with polar outer layer.
b. Albumin has more of nonpolar core with polar outer later while
aquaporins have more polar core with nonpolar outer layer.
c. Albumin has more polar core with non polar outer layer while
aquaporins have a more of non polar core with polar outer layer
d. Albumin has more polar core with polar outer layer while aquaporins
have a more of non polar core with non polar outer layer
6.The major protein component of human hair is α-keratin.
Hair ‘straighteners’ are commonly used tools which use heat
to iron hair into temporarily lying flat and straight. What is
the best biological explanation for this phenomenon?
a. Hair straitner denatures protein by disrupting the PH
b. Hair straitner disrupt hydrogen bonds in α-keratin
c. Hair stratner disrupt ionic bonds between α-keratin
molecules
d. Hair straitner disrupt disulphide bridges in α-keratin
7.A group of researchers isolate ‘Protein X’ from the wall of a human
stomach with the intent of learning how to synthesize stomach tissue
in the lab. Subsequently, they determine the exact sequence of amino
acids of the protein in its unfolded state, and create a functional
mRNA template to translate Protein X in vitro. They manage to
translate an exact copy of the polypeptide chain in the lab, but then
realize that it takes several days for the protein to fold into its final
tertiary structure. In vivo, they observe that several thousand copies
of Protein X are folded from polypeptide chains every minute. What
is NOT a plausible explanation for this difference in folding times?
a. The in vitro study lacks key enzymes
b. The temperature in vitro is too low
c. The in vitro study lacks key tRNA molecule
d. The in vitro PH is too high
8.A certain genetic disorder prevents the production of
signalling molecules which direct the intracellular trafficking
of proteins. If the disease exclusively affects the signal which
directs proteins to the proteasome, what primary effect
would most likely be observed?
a. Increased synthesis of proteins
b. Decreased degradation of proteins
c. Increased degradation of proteins
d. Decreased synthesis of proteins
9 .If the Golgi apparatus were damaged by an ingested toxin,
what aspect of protein synthesis would be most affected?
a. Translation
b. Beta sheet formation
c. Protein glycosylation
d. Alpha helix formation
A nonsense mutation has occurred in the DNA segment
which codes for “protein A”. After it has been transcribed and
translated, what is the most likely product formed from this
mutated region?
a. A small, truncated, nonfunctional “protein A”
b. A product that differs in only a single amino acid from
“protein A”
c. A product that differs in only a single base pair from “protein
A”, but with entirely different amino acids
d. A normally shaped, fully functional “protein A”
10 .Outline factors which does not affect pKa
value of an amino
acid
11. The following piece of double stranded DNA encodes a very
short peptide. In the space below, write the sequence of
mRNA that would be synthesized by RNA polymerase from
this piece of DNA if the bottom strand is the template. Then
write the protein sequence in one-letter code that would be
synthesized by the ribosome from that mRNA using the first
reading frame (use Genetic Code Table below).
i. 5’-ATGGCTGGGTGCTTTTAA-3’
ii. 3’ –TACCGACCCACGAAAATT-5’
12 .An element is a substance consisting of atoms that have the same number of protons in their atomic nuclei, such as gold, oxygen, and carbon.
2. A compound is formed when two or more different elements chemically react and bond together to form a new substance with different physical and chemical properties than its constituent elements.
3. Organic compounds are compounds that contain carbon atoms bonded to hydrogen atoms, often found in living organisms and their products, such as sugars, proteins, fats, and DNA.
4. Polar covalent bonds are formed by the unequal sharing of electrons between two atoms with different electronegativities, resulting in a partial positive charge on one atom and a partial negative charge on the other atom.
5. Hydrogen bonds can be found in body structures such as DNA and proteins, where they play important roles in maintaining the structure and function of these molecules.
6. Hydrogen bonding is a type of noncovalent bond that occurs between a hydrogen atom bonded to a highly electronegative atom like oxygen or nitrogen and another electronegative atom in a nearby molecule. This results in an attractive force between the molecules and can contribute to the properties of substances like water.
7. The two types of covalent bonding are polar covalent bonding and nonpolar covalent bonding.
8. Molar volume is the volume occupied by one mole of a substance, typically measured at standard temperature and pressure (STP).
9. i. To make 50 mL of 70% ethanol solution, you would need to calculate the amount of ethanol needed. Let x be the volume of 99% ethanol required, then the amount of ethanol in the final solution is 0.7 * 50 mL = 0.35 * x. Solving for x gives x = 66.67 mL of 99% ethanol.
ii. You would add (50 mL - 66.67 mL) = -16.67 mL or 16.67 mL of distilled water (depending on whether you want to add water first or ethanol first to the container).
iii. To prepare the 50 mL of 70% ethanol solution, you would mix 16.67 mL of distilled water with 66.67 mL of 99% ethanol in a container and stir well.
10. At STP, one mole of any gas occupies 22.4 L of volume. Therefore, 5 moles of CO2 gas would occupy (5 mol) * (22.4 L/mol) = 112 L of volume.
11. At Room Temperature and Pressure (RTP), one mole of any gas occupies 24.5 L of volume. Therefore, 80 L of NH3 gas would contain (80 L) / (24.5 L/mol) = 3.27 moles of NH3 gas.
12. Optical isomerism is a type of stereoisomerism that occurs when a molecule has a chiral center and exists in two non-superimposable mirror-image forms (enantiomers) that have different optical properties, such as the ability to rotate plane-polarized light in opposite directions.
13. Metamerism is a type of structural isomerism that occurs when two or more compounds have the same molecular formula but differ in the arrangement of their alkyl groups attached to a nitrogen or oxygen atom.
14. Chain isomerism occurs when compounds have the same molecular formula but differ in the length or branching of their carbon chains, while functional isomerism occurs when compounds have the same molecular formula but differ in their functional groups or the way they bond.
15. The IUPAC nomenclature for branching hydrocarbon structures involves identifying the longest continuous carbon chain (parent chain) and numbering its carbons to give the substituents (branches) the lowest possible numbers. The branches are named by adding the prefix of the substituent and the suffix "-yl," while the parent chain is named by adding the appropriate prefix and suffix based on the number of carbons in t
17.
18. Carbon is able to make large molecules due to its ability to form covalent bonds with up to