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Q.1)	Which statement is NOT a postulate of cell theory?

A.	The smallest unit of life is a cell

B.	All cells arise from pre-existing cells

C.	All living things are made of cells

D.	All cells evolved from many different of ancestral cells

E.	Cells grow, develop, and reproduce to pass on hereditary information

Q.2)	Which of the following statements concerning prokaryotes is TRUE?

A.	They have no nucleus and hence no DNA

B.	They have no Golgi apparatus

C.	They include bacteria, yeast, and protozoans

D.	They are all able to live on inorganic energy sources

E.	Both (b) and (c) are correct

Q.3)	What type of microscope would you use to look at ribosomes within a cell?

Q.4)	Mollicutes are ­­­__________ which have __________

A.	Simple eukaryotes; cytoskeleton structures

B.	Prokaryotes; cytoskeleton structures

C.	Simple eukaryotes; no nucleus

D.	Prokaryotes; no cell membrane

E.	Eubacteria; lysosomes

Q.5)	You have grown a culture of human cells and discover that it is heavily contaminated with bacteria.  Which of the following procedures will most likely eliminate the bacteria without killing the human cells?

A.	Treating the culture with a drug that causes microtubules to fall apart

B.	Diluting a small portion of the contaminated culture with 1000 times as much fresh nutrient broth and regrowing the cells.

C.	Treating the culture with a drug that damages DNA

D.	Treating the culture with a drug that dissolves cell walls

E.	Treating the culture with a detergent that destroys cell membranes

Q.6)	Which of the following evidence does NOT support the Endosymbiotic Theory?

A.	Chloroplasts and mitochondria contain their own DNA, RNA, and ribosomes

B.	Chloroplasts and mitochondria divide by binary fission

C.	Antibiotics inhibiting transcription in bacteria similarly affect chloroplasts and mitochondria

D.	The outer membrane of chloroplasts and mitochondria contain enzymes and proteins similar to prokaryotes

E.	Protein synthesis inhibitors that affect eukaryotic ribosomes do not affect protein synthesis carried out by prokaryotic ribosomes

Q.7)	Which of the following amino acid side chain is likely to form a hydrogen bond with water?

A.

Leucine

B.	Tryptophan

C.

Valine

D.

Threonine

E.	Phenylalanine

Q.8)	Side chains of amino acids are involved in bonding in

A.	Primary structure

B.	Secondary structure

C.	Tertiary structure

D.	Quaternary structure

E.	Both (c) and (d)

Q.9)	The α helix and β sheet are found in many different proteins because they are formed by

A.	Hydrogen bonding between the amino acid side chains most commonly found in proteins

B.	Noncovalent interactions between amino acid side chains and the polypeptide backbone

C.	Ionic interactions between charged amino acid side chains

D.	Hydrogen bonding between atoms of the polypeptide backbone

E.	Hydrophobic interactions between the many nonpolar amino acids

Q.10)	What bonds allow for the free rotation (flexibility) of the polypeptide backbone which allows for the wide variety of unique protein conformations?

A.	Peptide bonds between amino acids

B.	Covalent bonds within an amino acid

C.	Weak hydrogen bonds among polar amino acids

D.	The bond between the N-terminus of one amino acid and the C-terminus of another amino acid

E.	None of the above

Q.11)	A hemoglobin molecule is a heterotetramer which means it

Q.12)	Disulfide (S-S) bonds

A.	Are formed by the cross-linking of methionine and cysteine residues.

B.	Are formed mainly in proteins that are retained within the cytosol.

C.	Stabilize but do not change a protein’s final conformation

D.	Can be broken by oxidation through agents such as mercaptoethanol

E.	Rarely form in extracellular proteins

Q.13)	Which of the following is NOT true of a protein domain?

A.	It is composed of at least two different polypeptide chains

B.	It is an independently folding globular element of a protein

C.	It is composed of structures such as α helices and β sheets

D.	It is commonly linked to another domain through relatively unstructured regions of the polypeptide chain

E.	It plays an important role in the ability of enzymes to bind to substrates

Q.14)	A protein family consists of proteins that

A.	Have conserved amino acid sequences

B.	Have conserved secondary structures

C.	Have similar functions

D.	Have conserved tertiary structures

E.	All of the above

Q.15)	Which model allows you to best visualize secondary structures such as α helices and β sheets of a protein?

A.	Space-filling

B.

Backbone

C.

Ribbon

D.

Wire

E.	None of the above

Q.16)	What is column chromatography directly used for?

A.	To separate of proteins or peptide fragments based on charge, size, shape, and affinity for other molecules

B.	To obtain a 3-D model of a protein

C.	To determine the exact amino acid sequence of a protein

D.	To characterize the specific function of an enzyme

E.	To determine the number of bonds that exists within a segment of polypeptide chain

Q.17)	What can be used to cleave polypeptide chains in order to determine their amino acid sequence via comparison to cDNA libraries?

A.

Kinases

B.

Trypsin

C.

Proteases

D.	Sodium dodecyl sulfate

E.	Both (b) and (c)

Q.18)	Antibodies (immunoglobulins) can be used

A.	To produce protein crystals for x-ray crystallography

B.	As molecular tags

C.	As chaperones

D.	To enhance DNA recombination

E.	None of the above

Q.19)	A ligand primarily interacts with

A.	Amino acid side chains of a protein

B.	the polypeptide backbone of a protein

C.	the N-terminus of a protein

D.	the α carbons of a protein

E.	regulatory DNA sequence during transcription

Q.20)	What is NOT true of lysozymes?

A.	Lysozymes lower the activation energy required for hydrolysis to occur

B.	Lysozymes distort the position of a sugar molecule bringing the substrate closer to a transition state

C.	Glutamic acid and aspartic acid side chains of the lysozyme’s active site are involved in oligosaccharide catalysis

D.	lysozymes bring two disaccharides closer together to encourage a reaction to occur

E.	All of the above are true.

Q.21)	Kinases are responsible for

A.	removal of phosphate group

B.	cleavage of substrate using water

C.	repeated condensation reactions with similar building blocks to form a grown chain

D.	addition of phosphate group

E.	hydrolysis of nucleotide triphosphate

Q.22)	Enzymes catalyze a chemical reaction by __________ the activation energy, because they provide conditions favorable for the formation of a __________ intermediate called the __________ .

A.	lowering; high-energy; transition state

B.	increasing; high-energy; transition state

C.	lowering; low-energy; transition state

D.	increasing; low-energy; alternative state

E.	lowering; high-energy; alternative state

Q.23)	Retinal is...

A.	is a molecule that confers functionality to the rhodopsin protein

B.	is a protein that is responsible for vision in human

C.	is a chaperone of rhodopsin

D.	is one of four domains of rhodopsin

E.	is produced in the presence of vitamin K

Q.24)	A myosin head is moving along a microtubule in the direction shown in the figure below What will happen if you suddenly remove all ATP from the system by adding an enzyme that hydrolyzes ATP?

A.	No change. Myosin head will continue to move from point A to point B.

B.	Myosin head will wander back and forth along the microtubule.

C.	Myosin head will move backwards (toward point A instead of B).

D.	Myosin head will stall on the microtubule.

E.	Myosin head will continue to move from point A to point B, but at a slower rate.

Q.25)	RNA in cells differ from DNA in that

A.	it contains the base uracil, which preferentially pairs with cytosine.

B.	it is single-stranded and cannot form base pairs.

C.	it is single stranded can can fold up into a variety of structures.

D.	the nucleotides are linked together in different way

E.	the sugar ribose contains fewer oxygen atoms than does deoxyribose

Q.26)	Which of the following statements about the genetic code are correct?

A.	One codon specifies more than one amino acid

B.	The genetic code consists of 64 codons

C.	All amino acids are specified by more than one codon

D.	The genetic code is different in prokaryotes and eukaryotes

E.	All codons specify an amino acid

Q.27)	Which of the following statements is true

A.	Ribosomes are large RNA structures composed solely of rRNA

B.	RNA polymerase II is responsible for the transcription of rRNA

C.	The large subunit of a ribosome contains the catalytic activity that joins amino acids together

D.	a ribosome consists of two equally sized subunits

E.	a ribosome binds no less than three tRNA at one time

Q.28)	KM is a measure of

A.	substrate affinity of an enzyme

B.	enzyme performance

C.	catalytic rate of an enzyme

D.	ratio of [enzyme-substrate complex] to[unbound enzyme][unbound substrate]

E.	rate of enzyme degradation

Q.29)	What is an example of a GTP-binding protein?

A.

lysozyme

B.

Ef-Tu

C.	myosin head

D.	M-phase promoting factor (MPF)

E.	hemoglobin

Q.30)	What are ways in which proteins can be regulated?

A.	Allosteric regulation

B.	Feedback regulation

C.	GTP-binding

D.	ATP-binding

E.	All of the above

Q.31)	Which one of the following is the main reason that a typical eukaryotic gene is able to respond to a far greater variety of regulatory signals than a typical prokaryotic gene?

A.	Eukaryotes have three types of RNA polymerase

B.	Prokaryotes RNA polymerases require general transcription factors

C.	The transcription of a euakryotic gene can be influenced by many proteins that bind far from the promoter.

D.	Porkaryotic genes are packaged into tightly packed nucleosomes

E.	The protein-coding regions of eukaryotic genes are longer than those of prokaryotic genes

Q.32)	Which statement if FALSE?

A.	Eukaryotes have three types of RNA polymerase; prokaryotes have one type of RNA polymerase

B.	Chromatin rearrangement involving histone proteins is important in the regulation of gene expression in both eukaryotes and prokaryotes

C.	Activator proteins and repressor proteins are invovled in gene regulation in eukaryotes and prokaryotes

D.	Eukaryotic RNA polymerases require general transcription factors, while prokaryotic RNA polymerases do not.

E.	Eukaryotic mRNA transcript requires processing prior to translation, while prokaryotic mRNA transcripts require no processing prior to translation.

Q.33)	What enzyme catalyzes the formation of peptide bonds during translation?

A.	transferase A

B.	aminoacyl tRNA synthase

C.	methylmercaptnol

D.	ribosomal ATPase

E.	peptidyl transferase

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