test 2 (chapter 5,6,8,) Flashcards
What is a gene composed of
DNA that transcribes to produce an RNA molecule during transcription.
what is mRNA and what does it do
Messenger RNA and it provides the information for the ribosome to catalyze protein synthesis in translation.
what is gene expression?
the synthesis of a specific protein with a sequence of amino acids that is encoded into a gene.
What is central dogma
the flow of genetic information from DNA to RNA to protein.
what is a cells genotype
its full collection of its genes it contains.
What is a cells phenotype
The set of observable characteristics from those genes.
semiconservative replication
after replication each parent strand has a new and an old strand
What is DNA pol 3
is required from DNA synthesis and adds deoxyribose nucleotides one by one on the 3’ -OH strand.
what are DNA pol 1 and 2 for
repair.
what is a histone
a protein that provides structural support for a chromosome.
What happens if DNA is supercoiled?
it is inaccessible.
How does DNA get un-supercoiled?
Topoisomerase(gyrase)
What does helicase do
break the DNA structure by destroying the hydrogen bonds.
What nucleotide has fewer hydrogen bonds?
AT
What is primer?
a free 3’ -OH group that start the DNA synthesis.
what is primer synthesized by
RNA primase.
Ligase
Seals the gaps between the Okazaki fragments on the lagging strand to create one continuous DNA strand
DNA pol 1
Exonuclease activity removes RNA primer and replaces it with newly synthesized DNA
Topoisomerase II (DNA gyrase)
Relaxes supercoiled chromosome to make DNA more accessible for the initiation of replication; helps relieve the stress on DNA when unwinding, by causing breaks and then resealing the DNA
Topoisomerase IV
Introduces single-stranded break into concatenated chromosomes to release them from each other, and then reseals the DNA
A segment of DNA that codes for a functional product
gene
What process converts one parental DNA strand into 2 identical offspring molecules
transcription
In DNA replication the newly added nucleotide is joined to the growing DNA strand by
DNA polymerase
DNA polymerase adds nucleotides specifically to the what prime side of the growing strand?
3 prime
Which one of the following enzymes joins DNA
strands, joins Okazaki fragments, and mends
gaps in the DNA backbone during excision repair
DNA Ligase
What carries the coded information for making
specific proteins from DNA to ribosomes?
mRNA
Which molecules recognize specific codons and
transport amino acids to translate those specific
codons?
tRNA
A group of three nucleotides on mRNA is called
a(n)
codon
Transcription begins when RNA polymerase
binds to the DNA at the
promoter
of the 61 codons how many are sense codons
61 (3 are the telomeres)
between 60 to 80 percent of genes are not regulated by the cell but are ______ in nature
constitutive
What is the process that turns on the transcription
of a gene or genes?
induction
A group of genes that are transcribed together
and controlled by one promoter defines a(n)
operon
Inhibition of the metabolism of alternative carbon
sources by glucose is called
catabolite repression
ionizing radiation causes
DNA strand breaks
Single-stranded RNA molecules that inhibit
protein production in eukaryotic cells are known
as
microRNAs
thymine dimers can be repaired by light repair enzymes called
photolyases
What is the most common type of mutation which
involves single base pairs?
base substitution
Mutations in which one or a few nucleotide pairs
are deleted or inserted in the DNA are called
frameshift mutations
Approximately what percentage of substances
found by the Ames test to be mutagenic are also
carcinogenic in animals?
90%
The process of bacteria passing their genes to
other microbes of the same generation is known
as
horizontal gene shift
Transformation is the transfer of DNA from a
donor to a recipient cell via
naked DNA in solution
The process in which bacterial DNA is transferred
from a donor cell to a recipient cell inside a
bacteriophage is called
transduction
The process for gene transfer which requires cell-
to-cell contact and a particular type of plasmid is
called
conjugtion
Which type of plasmids carry genes for sex pili
and for the transfer of the plasmid to another cell?
conjugative plasmids.
What are the small segments of DNA that can
move from one region of a DNA molecule to
another?
transposons
The building of complex organic molecules from
simpler ones is called
anabolism
The breakdown of complex organic compounds
into simpler ones is called
catabolism
Inhibitors that fill the enzyme’s active site and
compete with the normal substrate are
competitive
Enzymes increase the speed of a chemical
reaction by
lowering the activation energy
Many apoenzymes are inactive by themselves
and must be activated by
cofactors
The addition of phosphate to a chemical
compound is called
phosphorylation
In what process does the aerobic electron
transport chain participate?
oxidative phosphorylation
A molecule that undergoes reduction
gains electrons
the energy from catabolic reactions is used to produce
ATP
In which one of the following processes is light
energy converted to ATP, which is then used to
synthesize organic molecules?
photosynthesis
In which one of the following processes is light
energy converted to ATP, which is then used to
synthesize organic molecules?
2 pyruvic acids, 2 atp, and 2 NADH
In prokaryotes, how many ATP molecules are
produced from the breakdown of one glucose via
aerobic respiration
38
The pentose phosphate pathway provides a
means to break down glucose and
five carbon sugars
The FIRST step in the Krebs cycle is combination
of an acetyl group with oxaloacetic acid, leading
to the formation of
citric acid
In anaerobic respiration, the final electron
acceptor is
an inorganic molecule other than oxygen
Where does photosynthesis take place in
eukaryotic cells?
chloroplasts
In the light-dependent reactions of photosynthesis
ADP is converted to ATP
In the Calvin-Benson cycle
carbon dioxide is used to synthesize sugars
Photosynthesis in plants, algae, and
cyanobacteria produces
oxygen
use electrons from reduced inorganic
or organic compounds as a source of energy and
CO2 as a source of carbon
chemoautotrophs
In cyclic photophosphorylation, the electrons
return to chlorophyll
In lipid biosynthesis, glycerol is derived from
dihydroxyacetone phosphate formed during
glycolisis
If an amine group added to a precursor comes
from a preexisting amino acid, the process is
called
transamination
The five-carbon sugars of nucleotides are
derived from either the
pentose phosphate pathway; entener duodorff pathway
Metabolic pathways that function in BOTH
anabolism and catabolism are called ________
pathways
amphiobolic
In fermentation
the final electron acceptor is organic.
an optimum PH for most bacteria is near
7
A psychrophile has an optimal growth
temperature of about
15C
Organisms that require high salt concentrations
for growth are called
obligate halophiles
What is/are the energy source(s) utilized by
primary producers in the hydrothermal vents on
the ocean floor?
sulfur compounds
Addition of salts preserves foods because they
increase osmotic pressure
Chemoautotrophs and photoautotrophs derive
their carbon from
carbon dioxide
Some microorganisms use gaseous nitrogen
directly from the atmosphere in a process called
nitrogen fixation
An organism that uses oxygen when present but
can grow without oxygen is called a(n)
facultative anaerobe
Which organism is killed by atmospheric oxygen?
obligate anaerobe
One of the following enzymes found in some
bacteria which can break down toxic hydrogen
peroxide into water and oxygen is
catalase
Generation time can best be defined as
the time it takes for a cell to divide.
Bacterial growth is usually graphed using
________ axis scales.
logarithmic
