Exam 1

A  Covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the sharing of protons between charged atoms.

B  Covalent bonds involve the transfer of electrons between charged atoms; ionic bonds involve the sharing of electrons between atoms.

C  Covalent bonds require carbon whereas ionic bonds do not.

D  Covalent bonds involve the sharing of pairs of electrons between atoms; ionic bonds involve the sharing of single electrons between atoms

E  Covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the between charged atoms.

A  The infectious strain cannot be killed by heating

B  The harmless strain somehow revived the heat-killed pathogenic bacteria.

C  The heat-killed pathogenic bacteria “transformed” the harmless strain into a lethal one.

D  the mice had lost their immunity to infection with S. pneumoniae

A  bonding together of several polypeptide chains by weak bonds

B  unique three-dimensional shape of the fully folded polypeptide

C  organization of a polypeptide chain into an a-helix or β-Pleated sheet

D  order in which amino acids are joined in a polypeptide chain

E  overall protein structure resulting from the aggregation of two or more polypeptide subunits

A  translation, replication, transcription

B  replication, transcription, translation

C  translation, transcription, replication

D  replication, translation, transcription

A  The sugar

B  All nucleotide are the same

C  The phosphate group

D  The base

E  The sugar and the base

A  A pH gradient

B  A temperature gradient

C  A density gradient

D  A salt gradient

A  recognition of the substrate by the enzyme

B  the maximum velocity of the catalytic reaction

C  the rate of product release by the enzyme

D  the rate of the reaction at ½ the maximum rate

A  modifying the N-terminal tails of core histones

B  recruiting other enzymes

C  using the energy of ATP hydrolysis to move nucleosomes

D  denaturing the DNA by interfering with hydrogen-bonding between base pairs.

A  heterochromatization

B  epigenetic inheritance

C  barrier destruction

D  Euchromatin depletion

A  membrane association

B  protein degradation

C  nuclear translocation

D  protein secretion

A  feedback inhibition

B  allosteric activation

C  oxidative phosphorylation

D  substrate-level phosphorylation

A  ΔH – T ΔS >0

B  things are moving from higher to lower concentration

C  ΔH – T ΔS <0

D  ΔH and ΔS are both positive and TΔH >H

E  ΔH – T ΔS =0

A  take place when the cells are at unusually high temperatures

B  take place very slowly

C  are catalyzed by enzyme

D  maybe coupled to the hydrolysis of ATP

E  are aided by various metal ions that act as catalysts

A  Enzymes reduce activation energy for the reactions they catalyze

B  The activity of enzymes cannot be regulated by factors in their immediate

C  Enzymes are proteins that function as catalysts

D  Enzymes display specificity for a certain molecules to which they attach or which attach to them

E  An enzyme maybe used many times over for a specific reaction.

A  high Vmax

B  low affinity for their substrate

C  low velocity of reaction

D  . high affinity for their substrate

A  irreversible inhibition and destruction of the enzyme molecule

B  negative feedback and allosteric inhibition/activation

C  competitive and non-competitive inhibition

D  negative feed-forward inhibition and homosteric activation

E  non-competitive inhibition and positive feedback.

A  the synthesis of large molecules from small molecules is exergonic

B  entropy increases in a closed system

C  The Earth is an open system

D  life exists at the expense of greater energy than it contains

E  every chemical transformed represents a loss of energy

A  They use energy derived from ATP hydrolysis to change the relative position of the DNA and the core histone octamer

B  They chemically modify core histones to alter the affinity between the histone octamer and the DNA.

C  They chemically modify the DNA, changing the affinity between the histone octamer and the DNA

D  They remove histone H1 from the linker DNA adjacent to the core histone octamer.

A  The polypeptide remains denatured.

B  The polypeptide adopts a new, stable conformation.

C  The polypeptide forms solid aggregates and precipitates out of solution.

D  The polypeptide returns to its original conformation.

A  recruitment of remodeling complexes

B  increase in gene expression

C  displacement of histone H1

D  gene silencing

A  C3H603

B  C6H1005

C  C18H36018

D  C18H32016

E  C18H30015

A  chromosome

B  heterochromatin

C  nucleosomes

D  euchromatin

E  nuclear pores

A  genome.

B  gene

C  coding sequence

D  genetic code

A  Double-stranded genomes have equal amounts of A and T

B  Single-stranded genomes have a higher rate of mutation

C  using the formula : G-A=C+T

D  single-stranded genomes always have a large percentage of purines

A  5’UAACGU3’

B  5’UGCAAU3’

C  3’UAACGU5’

D  5’TGCAAT3’

E  5’TAACGT3’

A  fluorescence

B  phase-contrast

C  bring-field

D  transmission electron

E  scanning electron

F  confocal

A  in allosteric activator domain

B  in the exact center of the protein

C  somewhere outside of the catalytic domain

D  At either the N or C terminus

E  inside the catalytic domain

A  cellulose

B  Protein

C  DNA

D  starch

E  glucose

A  genomics

B  structural biology

C  systems biology

D  proteomics

A  a β-Pleated Sheet

B  a peptide bond

C  an amino group

D  a disulfide bond

A  2,3,5

B  1,4,5

C  1,2,4,5

D  2,3,5

E  2,4,5

A  wavelength

B  filtering

C  intensity

D  absorption

A  water

B  molecular oxygen

C  methane

D  propane

A  vesicle transport

B  membrane support

C  cell motility

D  cell division

A  RNA can carry information and catalyze chemical reactions

B  Fossil evidence of such a molecule was recently discovered.

C  RNA is the only type of molecule that can catalyze a chemical reaction.

D  Self-replicating molecules of RNA exist today, in human cells

A  160g

B  800g

C  400g

D  125g

E  200g

A  digesting large food particles

B  primarily producing proteins in the cytosol

C  primarily producing proteins for secretion

D  constructing an extensive cell wall or extracellular matrix

E  enlarging its vacuole

A  protein

B  sugar

C  fat

D  fiber

A  Both contain endoplasmic reticulum and Golgi bodies.

B  Both can reproduce on their own outside of the cell

C  Both contain ribosomes that are identical to ribosomes of the eukaryotic

D  Both contain DNA molecules

E  Both have bacteria-like polysaccharide cell walls

A  in or near the active site

B  Such mutations could occur anywhere with equal probability

C  in regions of the protein that determine packaging into the virus capsid

D  at a cofactor binding site

E  at an allosteric site

A  plasma membrane

B  Golgi network

C  nuclear envelope

D  Mitochondrial membrane

A  ATP

B  RNA

C  complex cells

D  Ribozyme

E  DNA

A  Life on Mars tolerates the much higher levels of radiation found on Mars than life on Earth, which could be poisoned by the radiation

B  Studies of the earliest Mars and Earth cells show that they can both survive for many years in the harsh vacuum of space

C  Life on Mars uses a different genetic code (DNA & RNA) than life on Earth

D  The cells on Mars gain energy by using minerals found only on Mars., not on Earth.

A  polar covalent bonds

B  van der Waals interactions

C  ionic bonds

D  nonpolar covalent bonds

E  hydrogen bonds.

A  genome partially or completely sequenced

B  amenability to genetic manipulation

C  rapid rate of reproduction

D  ability to grow under controlled conditions.

E  All of the above is correct.

A  10

B  It is impossible to tell from the information given.

C  20

D  80

E  40

A  polar covalent bond formed between the oxygen and a hydrogen of single water molecule

B  hydrogen bond formed between the hydrogen of one water molecule and the oxygen of another water molecule

C  ionic bonds formed between the hydrogen of one water molecule and the oxygen of another water molecule

D  covalent bond formed between the hydrogen of one water molecule and the oxygen of another water molecule

A  hydrogen bonds

B  van der Waals interactions

C  ionic bonds

D  covalent bonds

A  requires the use of two sets of filters. The first filter narrows the wavelength range that reaches the specimen and the second blocks out all wavelengths that pass back up to the eyepiece except for those emitted by the dye in the sample.

B  uses a light microscope with an optical component to take advantage of the different refractive indices of light passing through different regions of the cell

C  scans the specimen with a focused laser beam to obtain a series of two-dimensional optical sections, which can be used to reconstruct an image of the specimen in three dimensions. The laser excites a fluorescent dye molecule, and the emitted light from each illuminated point is captured through a pinhole and recorded by a detector.

D  requires coating the sample with a thin layer of a heavy metal to produce three dimensional images of the surface of a sample

E  employs a light microscope and requires that samples be fixed and stained in order to reveal cellular details

F  has the ability to resolve cellular components as small as 2 nm.