CH. 8
IDENTIFYING DNA AS THE GENETIC MATERIAL
CH. 5 & 6 REVIEW
• ANSWER THE FOLLOWING QUESTIONS:
• 1. What macromolecule group does DNA & RNA belong in?
• 2. What monomer do we use to assemble the macromolecule
group from question #1.
CH. 5 & 6 REVIEW
• ANSWER THE FOLLOWING QUESTIONS:
• 3. What is a nucleotide?
• 4. What would a nucleotide for DNA contain?
• 5. What would a nucleotide for RNA contain?
• Ch. 8.1 – Identifying DNA as the Genetic Material
• Griffith finds a “transforming principle.” - NOTES
• Ch. 8.1 – Identifying DNA as the Genetic
Material
• Griffith finds a “transforming principle.”QUESTION & ANSWER:
• 1. What was “transformed” in Griffith’s
experiment?
• 2. Explain how the results support the
experimenters conclusion.
• Ch. 8.1 – Identifying DNA as the Genetic Material
• Avery Identifies DNA as the transforming principle - NOTES
• Ch. 8.1 – Identifying DNA as the Genetic
Material
• Avery Identifies DNA as the transforming
principle – QUESTION & ANSWERS:
• 1. How did Avery and his group identify the
transforming principle?
• 2. Explain how the results support their
conclusions for the transforming principle.
• Ch. 8.1 – Identifying DNA as the Genetic Material
• Hershey & Chase confirm that DNA is the genetic material – NOTES
• Ch. 8.1 – Identifying DNA as the Genetic Material
• Hershey & Chase confirm that DNA is the genetic material –
QUESTIONS & ANSWERS:
• 1. Summarize how Hershey & chase confirmed that DNA is the
genetic material.
• 2. Summarize why the bacteriophage was an excellent choice for
research to determine whether genes are made of DNA or proteins?
• 3. Explain how the results support their conclusions.
•LESSON OBJECTIVE
•1. What did Hersey & Chase know about bacteriophages
that led them to use these viruses in their DNA experiments?
•
8.2 – Structure of DNA
•DNA is composed of 4 types of
nucleotides (monomer):
•Nucleotide composed of:
•__________________ group
•______________________
•______________________
• DNA is composed of 4 types of nucleotides con’t.
• Nucleotide in _________________ is composed of:
• ____________________________________________________ group
• __________________________________________________________
• ____________________________________________________ base
• _________________________________________________ = C
• _________________________________________________ = T
• _________________________________________________ = A
• _________________________________________________ = G
• Nucleotide in __________________ is composed of:
• ____________________________________________________ group
• ____________________________________________________ sugar
• Nitrogen base
• Cytosine = C
• ____________________________________ = U (replaces thymine)
• Adenine = A
• Guanine = G
• Letter abbreviations refer both to the base & to the nucleotides that contain
that base
• DNA is composed of 4 types of nucleotides con’t.
• CHARGAFF’S RULE:
• ________ = __________
• ________ = __________
• QUESTION:
• What is the only difference among the 4 DNA
nucleotides?
• Which part of a DNA molecule carries the genetic
instructions that are unique for each individual; the
sugar-phosphate backbone or the nitrogencontaining bases? Explain.
• Watson & Crick Developed an accurate
model of DNA - NOTES
• Watson & Crick Developed an accurate
model of DNA – QUESTION & ANSWER:
• What bases are considered pyrimidines &
purines?
• Pyrimidines = ____________________
• Purines = ________________________
• How did the Watson & Crick Model
explain Chargaff’s rules?
• Nucleotides always pair in the same way.
• DNA nucleotides of a single strand are
joined together by _________________
bonds connecting the _____________ of
one nucleotide to the _______________
of the next nucleotide.
• Alternating sugars & phosphates form
the sides of a double helix sort of like a
________________________________.
• DNA double helix is held together by
____________________ bonds between
the __________________ in the middle.
• Nucleotides always pair in the same way –
QUESTIONS & ANSWERS:
• What sequence of bases would pair with
the following sequence: T T A C G C G A C
• 8.3 – DNA Replication
• Replication _____________________
the genetic information
• Watson & Crick’s experiments
showed that one strand of DNA is
used as a ______________________
to build the other strand
• Guarantees that each strand of
DNA is identical.
• Proteins carry out the process of replication
• How :
• DNA is unzipped at numerous places (H bonds
broken)
• Free floating nucleotides pair with the exposed
bases (template strands)
• ________________________________ bonds the
nucleotides together to form the new strands that
are complementary to the template strand
(original strand).
• Creates 2 identical molecules of DNA.
• Each DNA molecule has an __________________
& a ____________________________________.
• Why DNA replication is called
_____________________________ replication.
• DNA Replication
• Replication is fast & accurate
• Replication is fast because the DNA
strand is opened at ______________ of
different points & allowing nucleotides
to be added at many spots at the same
time.
• ________________ is carried out at the
_____ time that nucleotides are added.
• DNA polymerase can detect _________
& make _________________________.
• Pg. 238, fig. 8.9 shows this process
• 8.4 TRANSCRIPTION
• _______________ carries DNA’s instructions
• ______________________________________
• Information flows from ________ to _______
to _____________________________
• Transcription converts a DNA message into
an intermediate molecule, called RNA.
• Translation interprets an RNA message into
a string of ____________________, called a
polypeptide.
• Either a single polypeptide or many
polypeptides working together make up a
__________________________.
• RNA carries DNA’S instructions con’t.
• Prokaryotic cells:
• Replication, transcription, and
translation all occur in the ___________
at approximately the ___________ time.
• Eukaryotic cells:
• Replication, transcription, and
translation occur in ________________
locations.
• Replication & transcription – ________
• Translation – occurs in the __________
• RNA carries DNA’s instructions con’t.
• RNA acts as an intermediate link between
_______ in the nucleus & _____________
synthesis in the cytoplasm.
• Gets used then destroyed.
• RNA is ____________________, contains ribose
sugar & has _________________ instead of
thymine
• A (DNA) = U (RNA)
• T(DNA)= A(RNA)
• G (DNA) = C (RNA)
• C (DNA) = G (RNA)
• Transcription makes ___ types of ____
• ___________________ is the process
of copying a sequence of DNA to
produce a complementary strand of
RNA.
• Part of the chromosome, called a
_______, is transferred into an ____
____________________________.
• Transcription is catalyzed by RNA
polymerase.
• Transcription produces 3 major types of
RNA molecules
• _________________ (messenger RNA) –
an intermediate message that is
translated to form a ________________
• ______ (ribosomal RNA) – forms part of
ribosomes, a cell’s protein factories
• ____ (transfer RNA) – brings __________
_____ from the cytoplasm to a ribosome
to help make the growing ___________.
• Pg. 241, Fig. 8.11 visualizes transcription
• Transcription vs. replication
• Similarities
• Happen in __________________________ of eukaryotic cells
• Need enzymes to begin the process
• ______________________________ the DNA double helix
• Complementary ______________________ to the DNA strand
• _______________________________________ by the cell
• Differences
• ________________ makes sure each new cell will have ____
complete set of genetic instructions & occurs only once during
each round of the cell cycle.
• ___________________ could make hundreds or thousands of
copies of certain proteins or the rRNA or tRNA molecules need
to make _______________ based on the demands of the cell,
using a ____________ stranded complementary rRNA strand.
• 8.5 TRANSLATION
• Amino acids are coded by ______________ base
sequences
• Translation is the process that converts, or
translates, an mRNA message into a
___________________________________.
• Could be ___ or _________ polypeptides to
make up a protein
• Language of nucleic acids:
• DNA – uses 4 nucleotides = A, G, C, & T
• RNA – uses r nucleotides = A, G, C, & U
• Language of proteins uses ________________
• Triplet Code
• Genetic code uses ____________, which is read in groups of ___
nucleotide bases
• Codon is a 3 nucleotide sequence that codes for a particular
___________________, referred to as the __________________.
• First 2 nucleotides are usually the ____________ important in
coding for an amino acid
• ________________________ – signals the start of translation
and the amino acid is _______________________________
• 3 _________ codons – signal the end of the amino acid chain.
• If reading frame is ______________, changes protein or even
can prevent a protein from being made.
• Almost all organisms, including viruses, follows the _________
______________________.
• This allows scientists to insert a gene from 1 organism into
another organism to make a functional protein.
• GENETIC CODE
• Genetic Code
• DETERMINE WHAT AMINO ACID SEQUENCES ARE CREATED FROM
THE FOLLOWING STRINGS OF NUCLEOTIDES
• 1) A U G A C C A A C A G C
• 2) A U G C C C C A A U G A
• Amino acids are linked to become a protein
• Review:
• mRNA is a short lived molecule that
carries ______________ from ________
in the nucleus to the ________________
• mRNA message is read in groups of 3
nucleotides called ___________________
• How it translates the codon into an amino
acid requires the use of _______ &
__________ molecules
• Amino acids are linked to become a protein
• Ribosomes are made of a combination of rRNA & proteins &
they catalyze the reaction that forms the bonds between amino
acids.
• _____________________ have a large & small subunit that fit
together & pull the mRNA strand through.
• Small unit holds the mRNA strand & the large subunit holds
onto the growing protein
• _____________ carries _____________________________
from the cytoplasm to the ribosome
• Has an L shape to the tRNA molecule, one end of the L is
attached to the specific amino acid & the other end of the
L, is called the ____________________, which recognizes a
specific codon.
• Anticodon is a set of 3 nucleotides that is complementary
to an ___________________________ codon.
• PG. 246, Fig. 8.16 Translation, Read pg. 247
• 8.6 – GENE EXPRESSION & REGULATION
• mRNA processing
• Important part of gene regulation in eukaryotic cells
is RNA processing.
• mRNA that is produced by transcription needs to be
edited
• _____________ are nucleotide segments that code
for parts of the __________________________.
• _________________ are nucleotide segments that
are located ______________________ the exons
• Introns are _________________________ from
mRNA before it leaves the nucleus.
• Exons are ______________________________
back together
• 8.7 MUTATIONS
• Some mutations affect a single gene & others affect the entire
chromosome
• ________________________ is a change in an organism’s DNA
• Types of gene mutations:
• __________________ mutation – a mutation in which _____
nucleotide is _____________________________ for another.
• DNA polymerase could find & correct mistake, if not may
permanently change an organism’s DNA
• __________________ mutation – involves the ____________
or _________________________ of a nucleotide in the DNA
sequence
• Affects the polypeptide more than a point mutation
(substitution)
• Causes the ___________________________ from point of
insertion or deletion to change the remaining ___________
• MUTATIONS
• ORIGINAL NUCLEOTIDE SEQUENCE:
•A U G C C G U U A A C G C G A U C C G G
• READS:
• MUTATED NUCLEOTIDE SEQUENCE:
•A U G C A C G U U A A C G C G A U C C G G
• READS:
• Types of chromosomal mutations:
• Gene _______________________________:
• During ____________ chromosomes do _______
align & the chromosomal segments are different sizes.
The chromosome receiving the __________ segment
would have part of the chromosome that is
_________________________________.
• Gene deletion:
• During crossing over chromosomes do not align & the
chromosomal segments are different sizes. The
chromosome receiving the _____________ segment
would have part of the chromosome that is
________________________________________.
• Translocation:
• A piece of one chromosome ____________________
to a nonhomologous chromosome.
• Mutations may or may not affect phenotype.
• _______________________ – Collection of all of an organism’s
physical characteristics.
• Ex: black hair, blue eyes, attached ear lobes.
• Chromosomal mutations
• Usually have ______________ affect on organisms
• Ex: may break a gene causing it ___________ to function
• Ex: may create a ______ hybrid gene with a new function
• Ex: may cause a gene to be more or less active
• Gene mutations – could have a bad affect, no affect, or create a
beneficial mutation
• Could change the ______________________ for an enzyme
& now it cannot accept the ______________________
• Could affect how protein ___________ & possibly destroying
the protein’s ____________________________
• Could create a premature ___, making protein nonfunctional
• Impact on offspring
• Mutations can happen in _______ cells & in _______ cells.
• Body cell mutations ___________ affect that individual
• Germ cell mutations may be passed to ______________
• Can be source of ________________________, which
is the basis of ______________________________.
• Will affect the ______________________ of offspring
• Could be ______________& the offspring do _____
develop properly or could die before reproducing
• Could be mutations not well suited to environment
& the alleles will be _________ from the population
• Could be a mutation that is well suited to
environment & the alleles will be _______________
in the population
• Mutations can be caused by several
factors
• ______________________ – agents in the
environment that can change DNA.
• Speed up the rate of replication _______
• ____________________ DNA strands
• Cause __________________________
• Types of mutagens:
• _______________________________
• Industrial _______________________