uark Honors Biochemistry True False 2024 Dr. Thallapuranam exam 1

Homeostasis in an equilibrium process that occurs in living organisms

Homeostasis in an equilibrium process that occurs in living organisms

True

The systolic blood pressure reflects the contraction of the heart

True

All organic compounds are biochemicals but all biochemicals are not organic compounds

False: All biochemicals are organic compounds but all organic compounds are not biochemicals

The diastolic arterial blood pressure reflects the pressure between heart beats

True

The normal body temperature in humans is typically in the range of 98 C°to 100 C°

False: The normal body temperature in humans is typically in the range of 98 F°to 100F°

The structure of cells is largely due to proteins

True

Ribozyme is a protein

False: Ribozyme is RNA

Enzymes are derived from vitamins

False: Coenzymes are derived from vitamins

Lipids are reserve sources of cellular energy

True

Nucleic acids represent hereditary materials in cells

True

Water molecule has a bent chemical structure

True

Interactions between biomolecules is largely non-covalent

True

The dielectric constant of water is greater than that of ethanol

True

pH of cytoplasm of healthy cells is ~ 7.2-7.4

True

The force of attraction/repulsion between biomolecules is proportional to the square of the distance separating them

False: The force of attraction/repulsion between biomolecules is inversely proportional to the square of the distance separating them

The bond angle in the structure of water is greater than that in H2S

True

The electronegativity of the oxygen atom is lower than that of sulfur atoms

False: The electronegativity of the oxygen atom is greater than that of sulfur atom

The tendency of ethanol to form hydrogen bonding is lower than that of water

True

Electronegative atom, in a hydrogen bond, covalently bonded to the hydrogen atom is the hydrogen bond acceptor

False: Electronegative atom, in a hydrogen bond, non-covalently bonded to the hydrogen atom is the hydrogen bond acceptor

The unit of the magnitude of charge in a charged atom is Coloumbs

True

Newton is a M.K.S unit of energy

False: Newton is a M.K.S unit of force

Higher the dielectric constant of a solvent greater is its ability to screen charges

True

The units of the Coloumb/Force constant is N.C2.m_2

False: The units of the Coloumb/Force constant is N.C-2.m2

Water is a polar molecule

True

Hydrophilic biochemicals exhibit a tendency to interact with water

True

Natural amino acids are those that constitute proteins

True

There are 18 natural amino acids

False: There are 20 natural amino acids

Glycine is presumably the natural amino acid that has the least molecular mass as compared to its counter-part amino acids

True

Valine is a hydrophobic amino acid

True

The sidechain of alanine is a hydroxyl methyl group

False: The sidechain of alanine is a methyl group

Proline is the only natural amino acid

False: Proline is one of the natural amino acids

Both Ser and Asn are both hydroxyl group containing natural amino acids

False: Asn has a beta-amide group

Both M and C are both sulfur containing amino acids

True

V-I-L is a tripeptide comprising of Val-Ile-Lys

False: V-I-L is a tripeptide comprising of Val-Ile-Leu

His is a basic natural amino acid

True

Presence of Ser introduces a kink in the backbone of the structure of protein(s)

False: Presence of Pro introduces a kink in the backbone of the structure of protein(s)

Human hair is rich in cysteine

True

F contains phenolic group as the functional group

False: F contains phenyl/benzyl group as the functional group

Tyr contains indole group as its side-chain

False: Trp contains indole group as its side-chain

Arginine is a positively charged amino acid

True

A is considered as a hydrophobic natural amino acid

True

Isopropyl group is the functional group in Leucine

False: Isobutyl group is the functional group in Leucine

All aromatic amino acids are typically classified as hydrophobic amino acids

True

Histidine is frequently found in the active site of the enzyme

True

E is the single letter code of glutamine

False: Q is the single letter code of glutamine

The solvent dielectric signifies its ability to separate oppositely charged groups

True

Ethanol has a dielectric constant is 80

False: Ethanol has a dielectric constant is ~25

F,H, and W are aromatic amino acid

False: F,Y, and W are aromatic amino acids

The amino acids, D and E represent acidic amino acids

True

The amino acids N and Q are both polar uncharged amino acid

True

The pH of a 0.0001M solution of HCl is pH 3.0.

False: The pH of a 0.0001M solution of HCl is pH 4.0

The acid with a Ka value of 1 x10-5 is stronger the one with a Ka value of 1 x 10-3

False: The acid with a Ka value of 1 x10-5 is weaker the one with a Ka value of 1 x 10-3

Buffers are solutions containing mixtures of weak acid and a conjugate acid

False: Buffers are solutions containing mixtures of weak acid and a strong conjugate base

The amino acid, Serine, has a hydroxymethyl group as the functional group

True

Arginine has a guanidine group as the functional group

True

Zwitterions are molecular ions

True

Under physiological conditions, most amino acids exist as zwitterions

False: By definition, zwitterions are molecular ions whose net charge is zero. In this context, the acid and basic amino acids do not possess a net zero charge under physiological conditions. They either have a negative net charge or a positive charge, respectively. However, all neutral amino acids exist as zwitterions under physiological conditions.

At isoelectric point, an ionizable group has zero net charge

False: At isoelectric point, an amino acid (not an ionizable group) has a zero net charge.

Tyr is an essential amino acid

False: Tyr is not an essential amino acid

Complete proteins are rich in essential amino acids

True

D-mannose can potentially alleviate Urinary tract infections

True

D-allose is 6-carbon higher homologue of D-ribose

True

D-glucose and L-mannose are epimers

False: D-glucose and D-mannose are epimers

D-glucose and D-galactose are epimers

True

Galactosemia is a genetic disease manifested frequently in infants

True

UDP-Glucose is generic transporter of sugars

False: UDP-Glucose is dedicated transporter of glucose

Galactosemia individuals cannot convert galactose 1- phosphate to UDP galactose

True: The enzyme galactose -1 phosphate uridyl transferase is the defective enzyme and the products of the reaction are glucose 1—phosphate and UDP -galactose

Histidine is an essential amino acid in mammals

True

Galactosemia can be lethal if not adequately managed

True

UDP-Glucose is one of the reactants in the glycogen synthase pathway

True

Xylulose is an epimer of arabinose

False: Xylulose is not an epimer of arabinose

Tyrosine is an essential amino acid in mammals

False: Tyrosine is non-essential amino acid in mammals

Lyxose is the aldo pentose precursor of galactose

True

Lactose intolerance is typically not lethal

True

Psicose is a keto hexose

True

Erythrose is precursor of natural aromatic amino acids

True

Maltose is a disaccharide consisting on two glucose units

True

In the hydrogen bond between C=O and N-H, the nitrogen atom serves as the hydrogen bond donor

True

The sugar, D-mannose, is a preferred treatment to alleviate discomfort due to urinary tract infections

True

Maltose contains a alpha (1-4) glycosidic bond

True

Lactose is a milk sugar

True

Aldohexoses prefer to exist as furanose structures in solution

False: Aldohexoses prefer to exist as pyranose structures in solution

D-sorbose is a aldo hexose

False: D-sorbose is a keto hexose