Deck 1: Principles of Biochemistry

Question 1

Amino acids are the building blocks for which biomolecule(s)?

A) proteins
B) DNA
C) carbohydrates
D) micelles

Answer 1

proteins

Question 2

Plasmids are small, circular DNA molecules that are used in which of the following?

A) gene cloning
B) production of chromatin
C) cell movement
D) replication of nucleus

Answer 2

gene cloning

Question 3

The __________ differentiates amino acids from one another.

A) number of silane groups
B) number of phosphoryl groups
C) side chains attached to the central carbon
D) number of hydroxyl groups

Answer 3

side chains attached to the central carbon

Question 4

What is the function of the chloroplast in a plant cell?

A) detoxification of macromolecules
B) degradation of macromolecules
C) conversion of light energy to chemical energy
D) conversion of glucose to ATP

Question 5

Look at the bond energies O-H, N-H, and P-H in the table below. O-H is the hardest bond to break because it has the

A) greatest difference in relative affinities of the two atoms for electrons.
B) smallest difference in relative affinities of the two atoms for electrons.
C) smallest difference in atomic size.
D) largest difference in atomic size.

Question 6

Which two functional groups are involved in producing a peptide bond?

A) alcohol and amino
B) amino and thiol
C) methyl and amino
D) amino and carboxyl

Question 7

Enzymes function as reaction catalysts in cells. If the enzymes were removed from a cell, the rate of biochemical reactions would

A) increase.
B) remain the same.
C) decrease.
D) It is impossible to know.

Question 8

Given that methane (CH₄) has a bond angle of 109.5 $\degree$ and ethylene (C₂H₂) has a bond angle of 120 $\degree$ , what is the correct bond angle for acetylene (C₂H₂)?

A) 1.5 $\degree$
B) 160 $\degree$
C) 180 $\degree$
D) 360 $\degree$

Question 9

The correct definition of a pathway intermediate is a molecule that

A) is both a product and a reactant in a pathway.
B) lowers the activation energy of a reaction.
C) increases the rate of a reaction.
D) is only a reactant in a pathway.

Question 10

If the concentration of aspartate in the cell decreased, what would be the predicted outcome?

A) increased concentration of argininosuccinate
B) decreased concentration of citrulline
C) decreased concentration of fumarate
D) increased concentration of arginine

Question 11

Humans do not have the enzyme cellulase. Is it likely that a human could survive on a plant-only diet?

A) No, not enough ATP would be produced to generate energy.
B) No, not enough DNA would be produced to generate energy.
C) Yes, cellulase is not necessary to break down plant material.
D) Yes, ATP is not necessary to maintain life.

Question 12

A nucleotide consists of which of the following?

A) nitrogenous base, four-membered sugar and phosphate groups
B) phosphate base, four-membered sugar and sulfate groups
C) nitrogenous base, five-membered sugar and phosphate groups
D) carboxylic acid, four-membered sugar and phosphate groups

Question 13

Why are fewer polypeptide sequences encountered biologically than are theoretically possible?

A) There is no way to make all the theoretical possibilities.
B) The phosphodiester linkages don't allow for all the possibilities.
C) Not all have useful structural and functional properties.
D) Not all of the possibilities can be broken down.

Question 14

The essential ions calcium, magnesium, potassium, and sodium are all

A) anions.
B) cations.
C) transition metals.
D) halogens.

Question 15

Simple sugars are made of which of the following elements?

A) carbon, sulfur, and hydrogen
B) carbon, oxygen, and phosphate
C) carbon, oxygen, and helium
D) carbon, oxygen, and hydrogen

Question 16

The birth of modern biochemistry can be traced to the

A) end of the 19th century.
B) end of the 20th century.
C) beginning of the 19th century.
D) beginning of the 21st century.

Question 17

Even though amylose and cellulose contain the same repeating unit of glucose, they are very different in terms of function. Why?

A) A glycosidic bond cannot be cleaved.
B) The orientations of the glycosidic bond are different.
C) ATP cannot be generated from amylose.
D) There is no structural difference between the polymers.

Question 18

If the concentration of F is high in a cell, the pathway will MOST likely shift to produce

A) more C.
B) less C.
C) more A.
D) less D.

Question 19

The study of biochemistry attempts to explain

A) chemical processes at the atomic level.
B) biological processes at the molecular and cellular level.
C) the nature of life.
D) physical processes at the macromolecular level.

Question 20

If energy in the form of ATP is required to make a polymeric macromolecule, which of the following will happen if there is no ATP available?

A) The rate of polymer increases.
B) The polymer is broken down to release ATP.
C) The polymer continues to be made at the same rate.
D) The enzyme degrades to release ATP.

Question 21

Bioinformatics shows that 98% of human DNA is identical to that of chimpanzees. If human DNA contains 3.2 billion nucleotides, how many nucleotides are different between the two species?

A) 3.1 billion
B) 64 million
C) 3.1 million
D) 640 million

Question 22

What structural feature of DNA is attributed to the fact that the two DNA strands are antiparallel?

A) DNA is a left-handed helix.
B) DNA has the phosphate groups on the interior.
C) DNA is a right-handed helix.
D) DNA forms a pleated sheet.

Question 23

The amino acid sequence of a protein determines its structure. Which of the following statements is true?

A) Two proteins with similar amino acid sequence should have similar structures.
B) Two proteins with different amino acid sequences will have identical structures.
C) Two proteins with similar amino acid sequences will always have the same function in a cell.
D) It is impossible to determine how proteins will fold based on the amino acid sequence alone.

Question 24

Who received the Nobel Prize in 1962 for elucidating the molecular structure of DNA?

A) Albert Einstein
B) Linus Pauling
C) John Kendrew and Max Perutz
D) Maurice Wilkins, James Watson, and Francis Crick

Question 25

The RNA world model is based on the hypothesis that is stable.

A) RNA
B) DNA
C) uracil
D) adenine

Question 26

If a plasma membrane is hydrophobic, what kinds of amino acids are MOST likely to be found in the membrane?

A) hydrophilic amino acids
B) hydrophobic amino acids
C) polar amino acids
D) charged amino acids

Question 27

A single nucleotide base substitution in a wild-type DNA is an example of

A) random mutation.
B) transcription.
C) translation.
D) cloning.

Question 28

A segment of DNA containing 20 base pairs includes 8 adenine residues. How many uracil residues are present?

A) 12
B) 8
C) 0
D) 28

Question 29

The appearance of new gene speciation is an example of

A) gene multiplication.
B) gene singulation.
C) gene duplication.
D) random mutation.

Question 30

An inherited disease comes from the mutation of DNA in a cell.

A) somatic
B) germ-line
C) adipose
D) blood

Question 31

How does the molecule adenosine monophosphate fit into the seven hierarchical levels that define the chemical basis of life?

A) element/functional group
B) biomolecule
C) metabolism
D) organism

Question 32

A hydrogen bond can best be described as a

A) strong covalent interaction.
B) strong ionic interaction.
C) weak noncovalent interaction.
D) weak covalent interaction.

Question 33

When a ligand binds to a receptor, it causes the receptor to

A) degrade.
B) activate.
C) deactivate.
D) rapidly grow.

Question 34

The "central dogma of molecular biology" can best be described as the transfer of information between

A) nucleic acids and proteins.
B) fatty acids and proteins.
C) carboxylic acids and proteins.
D) nucleic acids and DNA.

Question 35

If a mutation was made to the gene for glucose-6-phosphate dehydrogenase that prevented it from functioning, a possible outcome would be the production of

A) more NADPH.
B) less NADPH.
C) more ATP.
D) less ATP.

Question 36

Given a DNA sequence of 3 ^' -CAT-5 ^' , what is the complementary sequence in mRNA?

A) 5 ^' -GUA-3 ^'
B) 5 ^' -AUG-3 ^'
C) 3 ^' -GUA-5 ^'
D) 5 ^' -GTA-3 ^'

Question 37

Why can a guanine not be paired with adenine?

A) Guanine is only found in RNA and adenine is found only in DNA.
B) Guanine can form three hydrogen bonds and adenine can form two.
C) Guanine can form only two hydrogen bonds and adenine can form three.
D) Guanine can only pair with thymine.

Question 38

A genome is a set of

A) proteins.
B) transcripts.
C) genes.
D) genetic code.

Question 39

Highly conserved gene sequences that encode proteins with the same function in different organisms are called genes.

A) orthologous
B) conserved
C) parallel
D) antiparallel

Question 40

The main difference between deoxyribonucleotides and ribonucleotides is that they have a different

A) number of carbons in the sugar ring.
B) functional group on the 2 ^' carbon.
C) number of phosphates on the 5 ^' carbon.
D) functional group on the 3 ^' carbon.

Question 41

What is the maximum number of covalent bonds a carbon atom can make?

A) 2
B) 4
C) 6
D) 8

Question 42

Pyruvate decarboxylase converts pyruvate into

A) carbon dioxide and acetaldehyde.
B) carbon monoxide and acetaldehyde.
C) water and glucose.
D) ethanol and carbon dioxide.

Question 43

An example of experimental biochemistry is trying an experiment and

A) quitting after it fails to prove your hypothesis.
B) continuing to try with no changes to protocol.
C) optimizing experimental design.
D) successfully proving your hypothesis after the first attempt.

Question 44

Which of the following is NOT a common functional group?

A) COOH
B) CH₃
C) SH
D) CHO

Question 45

Ribose is a

A) four-carbon sugar.
B) five-carbon sugar.
C) six-carbon sugar.
D) five-carbon acid.

Question 46

mRNA is used for what process in the cell?

A) as a template for protein synthesis
B) regulation of gene expression
C) regulation of RNA
D) replication of DNA

Question 47

The proposal that DNA is a double helix was based on what experimental evidence?

A) NMR
B) IR
C) HPLC
D) x-ray crystallography

Question 48

What is the cause of the overall negative charge of a molecule of DNA?

A) hydrogen bonding between base pairs
B) the phosphate backbone
C) the sugars
D) the antiparallel orientation of the DNA

Question 49

Hydrogen bonds form between hydrogen and

A) oxygen.
B) helium.
C) carbon.
D) hydrogen.

Question 50

Which of the following is an example of an ecosystem?

A) mammals
B) plasma membrane
C) insects
D) forest

Question 51

In structures of tRNA, base pairs form between

A) the same strand.
B) another strand of RNA.
C) a strand of DNA.
D) Base pairs do not form.

Question 52

Which of the following is an example of a metabolic pathway?

A) mitochondria
B) organelles
C) glycolysis
D) plasma membrane

Question 53

Mutations to proteins typically occur starting

A) at the protein itself.
B) with mRNA.
C) with tRNA.
D) with DNA.

Question 54

By convention, nucleic acid chains are written starting at the end.

A) amino
B) carboxyl
C) 3 ^'
D) 5 ^'

Question 55

A requirement for a covalent bond to form between two atoms is that

A) there are unpaired electrons on each atom.
B) the atoms are ions.
C) both the atoms must be metals.
D) one of the atoms must be a halogen.

Question 56

The correct name for the VSEPR arrangement around a carbon in methane is

A) linear.
B) trigonal bipyrimidal.
C) tetrahedral.
D) octahedral.

Question 57

The DNA double helix is stabilized by the interactions between nucleotides because of __________ between nucleotides.

A) hydrogen bonding
B) pi-pi stacking
C) sigma bonds
D) ionic interactions

Question 58

In DNA the phosphate groups are on the outside of the helix. Why does this stabilize the structure?

A) ionic interactions with the solvent
B) hydrogen bonding with itself
C) covalent binding to the solvent
D) It does not stabilize the structure.

Question 59

The process of fermentation uses sugar to produce which molecules?

A) alcohol and carbon monoxide
B) alcohol and carbon dioxide
C) acid and carbon monoxide
D) acid and carbon dioxide

Question 60

What side products of pyruvate are being converted into alcohol and carbon dioxide by yeast?

A) CO and NADH
B) CO₂ and NADH
C) CO₂ and NAD⁺
D) CO and NAD⁺

Question 61

Identify the following biomolecules.

Question 62

Identify the following functional groups.

Question 63

What process describes using mRNA templates to produce proteins?

A) DNA transcription
B) DNA replication
C) DNA translation
D) mRNA translation

Question 64

Cell signaling and cell membranes are examples of functions performed by which biomolecule?

A) amino acid
B) nucleotide
C) simple sugar
D) fatty acid

Question 65

Enzymes and chromosome are found where in the bacterial cell?

A) nucleoid
B) pili
C) cytoplasm
D) capsule

Question 66

The function of chloroplasts in plant cells is to convert

A) heat energy to light energy.
B) heat energy to chemical energy.
C) light energy to chemical energy.
D) chemical energy to heat energy.

Question 67

Proteins are a polymer of __________, whereas nucleic acids are polymers of _.

A) nucleotides; fatty acid esters
B) nucleotides; amino acids
C) amino acids; nucleotides
D) sugars; nucleotides

Question 68

What process replicates DNA to make more DNA?

A) DNA transcription
B) DNA replication
C) DNA translation
D) RNA transcription

Question 69

List three examples of how biochemistry has made advancements in the lives of many humans.

Question 70

Triacylglycerols are neutral molecules made of

A) three fatty acid esters covalently linked to glycine.
B) three fatty acid esters covalently linked to glycerol.
C) two fatty acid esters covalently linked to glycine.
D) three acyls covalently linked to glycerol.

Question 71

Which of the following is the correct formula for glucose?

A) C₅H_{1 0}O₅
B) C₆H_{1 2}O₆
C) C₅H_{1 2}O₆
D) C₆H_{1 0}O₆

Question 72

What process converts DNA to RNA?

A) DNA transcription
B) DNA replication
C) DNA translation
D) RNA transcription

Question 73

Cyclic pathways contain several metabolites that regenerate during each turn of the cycle. Another way to describe a metabolite is that it functions as a

A) reactant or product.
B) catalysis.
C) transition state.
D) enzyme.

Question 74

ATP is an abbreviation for which energy currency molecule?

A) adenosine triphosphate
B) adenosine thymine
C) adenosine dinucleotide
D) amino triphosphate

Question 75

The figure below shows an example of which functional group?

A) amino
B) hydroxyl
C) phosphoryl
D) methyl

Question 76

Which six elements make up 97% of the weight of most organisms?

Question 77

What is another way to describe the amphipathic nature of a fatty acid?

A) polar head and nonpolar tail
B) nonpolar head and polar tail
C) polar head and double bonds in tail
D) nonpolar head and double bonds in tail

Question 78

What are the three biochemical principles that together provide a framework for understanding life at the molecular level? How are they interrelated?

Question 79

Vitamin B₂ is a metabolite. Lack of vitamin B₂ can lead to blurred vision and a swollen tongue. Vitamin B₂ has such a strong effect on health because metabolites

A) are the catalysts that drive biochemical reactions necessary for life-sustaining processes.
B) are complex chemical reactions in cells.
C) process essential genetic information needed for life.
D) are needed for construction of microtubules.

Question 80

What does chromatin in eukaryotic nucleus contain?

A) DNA packaged with proteins.
B) RNA packaged with proteins.
C) ATP packaged with proteins.
D) DNA packaged with ATP.