Reading Check 13.1
Complete this outline while you read section 13.1 of your textbook. You do not
need to answer in complete sentences.
Chapter 13, Section 1: Structure of DNA
DNA: The genetic material
DNA is an abbreviation for _____________________________ ______________.
A few key _____________________________ led to the discovery that DNA is the genetic material.
Searching for the genetic material
Frederick Griffith studied strains of _____________________________ and reached the conclusion
that the genetic material could be transferred between _____________________________. He
called the process by which a cell takes up foreign genetic material
_____________________________.
Hershey and chase studied _____________________________, viruses that infect bacteria. They
concluded that only the _____________________________ of viruses was injected into bacteria,
suggesting that DNA, not _____________________________, were the hereditary material.
Shape of DNA
The spiral shape of DNA is known as the ________________________ ________________________.
Each parallel strand of DNA is made up of linked subunits called ____________________________.
A nucleotide consists of a _____________________________, a _____________________________ and
a nitrogenous _____________________________.
Information in DNA
The base pairing rules state that adenine always pairs with _____________________________
and _____________________________ always pairs with cytosine. These rules were discovered by
_____________________________. Using X-ray diffraction images of DNA, _______________________
and ______________________ discovered that it resembled a tightly coiled ____________________.
Building on these findings, it was ___________________________ and ___________________________
who first determined the three-dimensional structure of DNA.
Reading Check 13.2
Complete this outline while you read section 13.2 of your textbook. You do not
need to answer in complete sentences.
Chapter 13, Section 2: Replication of DNA
DNA replication
In DNA replication, the DNA molecule _____________________________ and the two sides split.
Then, new _____________________________ are added to each side until two identical sequences result.
Replication proteins
Proteins called DNA _____________________________ unwind the DNA double helix. Other
proteins called DNA _____________________________ add nucleotides that pair with each base to
form two new double helixes. DNA polymerases also have a _____________________________ function.
Prokaryotic and eukaryotic replication
In _____________________________ cells, replication starts at a single site. In
_____________________________ cells, replication starts at many sites along the chromosome.
Because multiple _____________________________ forks are working at the same time, an entire
human chromosome can be replicated in about _______ hours.
Reading Check 13.3
Complete this outline while you read section 13.3 of your textbook. You do
not need to answer in complete sentences.
Chapter 13, Section 3: RNA and gene expression
Overview of gene expression
________ provides the original information from which proteins are made in the cell. However,
it does not make proteins. A second type of nucleic acid, called ________, is essential in taking the
genetic information from DNA and then building proteins.
Gene expression produces proteins by ________________________ and ________________________.
_____________________________ refers to making RNA from the information in DNA.
_____________________________ uses the information in RNA to make a specific protein.
RNA: A major player
RNA is composed of one strand of _____________________________, rather than two strands.
RNA nucleotides contain the sugar _____________________________, rather than deoxyribose.
RNA nucleotides have a nitrogen base called _____________________________ instead of the
base thymine. Like thymine, uracil is complementary to _____________________________.
_____________________________ RNA is the type of RNA that carries instructions for making a protein from
DNA and delivers them to the site of translation.
_____________________________ RNA translates the mRNA sequence into a specific sequence of
amino acids. Protein production occurs on _____________________________. The RNA that is
found in ribosomes is called _____________________________ RNA.
Transcription: Reading the gene
During transcription, the information on a specific region of DNA is
_____________________________, or copied, into _____________________________, The process is
carried out by a protein called RNA _____________________________.
Genetic code: Three-letter “words”
Once a section of gene is transcribed into mRNA, the “words” can be carried from the
_____________________________ to the ribosomes in the _____________________________. There, they are used
to make proteins. The genetic code is based on three-nucleotide sequences
called _____________________________, that each represent a specific amino acid.
Translation: RNA to proteins
Translation occurs in the _____________________________, Each _____________________________
molecule carries the amino acid that corresponds with the tRNA’s __________________________.
Reading Check 14.1
Complete this outline while you read section 14.1 of your textbook. You do not need
to answer in complete sentences.
Chapter 14, Section 1: Mutation and genetic change
Mutation: The basis of genetic change
A mutation is a change in the _____________________________ or _____________________________ of genetic
material of an organism.
Mutations occur naturally as accidental changes to _____________________________ or to
_____________________________ during the cell cycle. The rate of mutation can be increased by
environmental factors called _____________________________, which include radiation and some chemicals.
A mutation may have no effect, or may ________________________ or ________________________ in some way.
Several kinds of mutations
A _____________________________ mutation is a change of a single nucleotide in a sequence from one
base to another.
Rarely, one or more nucleotides may be _____________________________ or
_____________________________ from a sequence.
A mutation is _____________________________ when it has no effect on a gene’s function.
A _____________________________ mutation results when a codon is changed such that the new
codon codes for a different _____________________________ _____________________________.
An insertion or deletion can shift the reading frame, causing a _____________________________.
A _____________________________ mutation results when a codon is changed to a stop signal. In
this case, the resulting string of _____________________________ _____________________________ may be cut
short.
In eukaryotic cells, the process of _____________________________ creates the chance of
mutations to chromosomes. A _____________________________ occurs when a piece of
chromosome is lost. _____________________________ occurs when a piece remains attached to
its homologous chromosome after meiosis. An _____________________________ occurs when a piece
reattaches to its original chromosome, but in a reverse direction. A
_____________________________ occurs when a chromosome piece ends up in a completely
different, nonhomologous chromosome. A gene _____________________________ can move an entire gene
to a new location.
Reading Check 15.1
Complete this outline while you read section 15.1 of your textbook.
You do not need to answer in complete sentences.
Chapter 15, Section 1: The human genome
Secrets of the human genome
The term _____________________________ refers to all of the genetic material in an organism,
population or species. _____________________________ is the study of entire genomes,
especially by using technology. Recently, it has been possible to ____________________________ the
human genome.
The _____________________________ _____________________________ _____________________________
was an international effort to sequence the 2.9 billion ___________________ ___________________ that make
up the human genome.
Scientists found that humans have only about _____________________ genes.
If the DNA of any two people is compared, ________ % is identical.
Applications of human genetics
Genetic _____________________________ refers to the transfer of genes from one organism to another.
A _____________________________ shows what genes are being actively transcribed in a sample from a
cell. This can be used to diagnose genetic disorders or cancer.
Genetic _____________________________ informs people about the risk of genetic problems that could
affect them or their offspring.
_____________________________ made through genetic engineering may limit dangers of using natural
vaccines to prevent diseases.
Gene _____________________________ means inserting a functional gene into a person’s cells.
DNA _____________________________ are used to confirm the identities of criminals, family members or
dead bodies.
Reading Check 15.2
Complete this outline while you read section 15.2 of your textbook. You do
not need to answer in complete sentences.
Chapter 15, Section 2: Gene technology in our lives
Manipulating genes
Genetic _____________________________ is the deliberate alteration of the genetic material of
an organism. DNA that has been recombined in this way is called ___________________________ DNA.
Today, genetically _____________________________ organisms, or GMOs, are widely used in agriculture,
medicine, industry and basic research.
Manipulating bodies and development
A clone is an organism of piece of genetic material that is _____________________________
_____________________________ to one that was preexisting. _____________________________, a cloned sheep,
was born in 1997.
A _____________________________ cell can continuously divide and differentiate into different
tissues. _____________________________ cells can give rise to any cell or tissue type,
_____________________________ cells can give rise to all types except germ cells, and
_____________________________ cells can give rise to just a few other cell types.
Ethical and social issues
One danger of GMOs is that we might not know enough to safely __________________________ genes on
a large scale.
Today, the DNA of individuals can be tested to find the risk of genetic
_____________________________, but who should have access to that information?
Now, it is possible to patent specific DNA _____________________________.