Final Exam
oxidation
loss of electrons
If two atoms are joined by a polar covalent bond, the shared electrons will tend to stay closer to the atom with which of the following characteristic?
The higher electronegativity
Which bond is stronger, ionic or covalent?
covalent
Telomerase is unique because it contains
an RNA molecule
What is an amino acid?
building blocks of proteins
What is a nonpolar covalent bond?
electrons are shared equally
What is a polar covalent bond?
unequal sharing of electrons
The enzyme that travels along the leading strand assembling new nucleotides on a growing new strand of DNA is
DNA polymerase III
If DNA ligase was nonfunctional, what would be a likely consequence?
DNA replication would occur, but the lagging strand would have numerous single-strand breaks.
When an acid is dissolved in water, how does it change the solution's pH?
It decreases the solution's pH by releasing protons in the solution.
protein motif
a reoccurring combination of secondary structures
A substance that increases [H+] and decreases pH when it dissociates in water is called a(n)
acid
A ____________is a substance or a mixture of substances that act to resist changes in pH.
buffer
secondary protein structure
coiling or folding of a polypeptide due to H-bonding between amino acids
reduction
gain of electrons
What is a nucleic acid?
polymer of nucleotides
quaternary protein structure
protein consisting of more than one amino acid chain
DNA polymerases cannot replicate
the 3' end of linear chromosomes.
f two atoms are joined by a polar covalent bond, the atom with the lower electronegativity will have a partial _____________ charge
+
Cohesion
when water sticks to itself
adhesion
when water sticks to other things
What is a disaccharide?
two sugars
what is the purpose of a buffer
minimize change in pH
tertiary protein structure
occurs when certain attractions are present between alpha helices and pleated sheets
dehydration synthesis
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
solvent
A liquid substance capable of dissolving other substances
Monomer
A simple compound whose molecules can join together to form polymers
Evaluate the statements below and determine which is the best explanation for why bacteria don't use telomerase.
Bacteria have circular chromosomes that do not shorten.
Hydrolysis
Breaking down complex molecules by the chemical addition of water
isomer
Compounds with the same formula but different structures.
what is the difference between DNA and RNA
DNA is double stranded and RNA is single stranded
Which of the following best describes the function of telomerase at the telomere?
It adds new DNA to the longer strand of the telomere overhang.
What does it mean when we say water is adhesive?
It is attracted to other polar molecules and ions.
What might result for a eukaryotic organism that lacked functional telomerase?
It would have shorter chromosomes with every round of mitosis, leading to abnormal cells.
Electrons that are closer to the nucleus always have which of the following?
Less potential energy
Before the lagging strand can begin assembling new DNA nucleotides, which of the following must occur?
Primase constructs a short RNA primer.
protein domain
Segment of a polypeptide chain that can fold into a compact stable structure and that usually carries out a specific function.
The enzyme that unwinds a segment of the DNA molecule is
helicase
Polymer
large compound formed from combinations of many monomers
primary protein structure
sequence of amino acids
hydrolysis reaction
splitting of a chemical bond by the addition of water