Download DNA Student Questions

Background Information” DNA and gel electrophoresis.
A. The structure of DNA
1. DNA, or __________________________
, is a very large molecule called
a_____________. Polymer means _____________________________. The units
or monomers of DNA are called ____________________.
a. Nucleotides are made up of a __________________ called
________________ a ______________group and one of
four_____________________. The bases use letters to shorten their names.
1. A is for ________________
2. G is for _________________
3. C is for _________________
4. T is for __________________
b. ____________ Bases -- Adenine and guanine are purines. ______________
are the larger of the two types of bases found in DNA. They have a
_____________ ___________ structure.
c. _______________ Bases -- Cytosine and thymine are pyrimidines. They have
a _________________________ structure.
2. __________________ Sugar -- The deoxyribose sugar of the DNA backbone has
_____________________________ atoms. The hydroxyl groups carbons link to
the ___________________ groups to form a DNA backbone.
3. DNA is composed of twisting strands of ________________. Each strand is a
____________ or spiral staircase. The two strands bound together make DNA a
double helix.
4. In the structural configuration of DNA, __________________ always join
together and form two hydrogen bonds while ________________ always join
together and form three hydrogen bonds. Because of the specificity of base
pairing, the two strands of DNA are said to be ____________________. This
characteristic makes DNA unique and capable of transmitting
______________________________.
B. DNA Fingerprinting
1. DNA Fingerprinting is a method of identification that compares
___________________. DNA is the genetic material found within the cell
______________. An individual's DNA is as distinctive as a fingerprint. With the
exception of ________________, the complete DNA of each individual is unique.
Student work in Paint
2. A DNA fingerprint is constructed by first obtaining a DNA sample from
_____________________________. The sample is then cut into pieces using
________________ and the segments are arranged by size using a process called
___________________________.
3. Gel electrophoresis is a method that separates macromolecules like DNA on the
basis of ___________, _____________________, and other physical properties.
a. A gel is similar to Jell-O in consistency. The term electrophoresis describes
the migration of charged DNA particles under the influence of an
____________________. Electro refers to the energy of
_________________. Phoresis, from the Greek verb phoros, means
"_________________." Thus, gel electrophoresis refers to the technique in
which molecules are forced across a span of gel motivated by an
_________________________.
b.
Holes are created in the gel that serves as a ____________ to hold the DNA
solution.
c. DNA solutions (mixtures of different sizes of DNA fragments) are loaded into
a _____________ in the gel.
d. The _____________ acts as a sieve for DNA molecules.
___________________ have difficulty getting through the holes in the matrix.
Small molecules move easily through the holes because of this, large
fragments will lag behind small fragments as DNA migrates through the gel.
e. Results are usually _________________ in order to save the findings. Wells
are then compared together for similarities. If two fingerprints match they are
probably from the same DNA source (i.e. Crime scene blood and suspect blood.)
4. DNA fingerprinting technology has helped scientists to discover the
__________________ of many disease processes. Mapping the entire
________________ (all of our DNA) has been one of the most massive scientific
endeavors of all time. The complete human genome was completed in
__________.
1. DNA fingerprinting helped advance ____________________________________.
Which 2 DNA samples match? ___________________________
A
B
C
D