Download atgccaatgggatc

Ms. Bruno
DNA
Regents Biology
Name __________________________________________________________
Date ______________ Per _______
DNA: The Code of Life!
DNA is the molecule that contains all of the
________________ material for an organism
It is found ONLY in the _______________ of
eukaryotic cells
DNA is also a _____________ __________,
which means it is composed of thousands of
subunits called ______________________
Each nucleotide in DNA consists of
1.
2.
It’s a Double Helix!
3.
In ________, Dr. James ______________ and
Dr. Francis ______________ developed a
model of the DNA molecule that showed DNA is
a “double helix,” or a ___________________
______________
Composition of the Ladder:
The __________ of the “ladder”
are formed by a backbone of
___________________ and
_____________________
molecules
Meet the Nitrogenous Bases!
The nitrogenous bases that make up
the “rungs” of the DNA ladder are:
____________________ (A)
____________________ (T)
____________________ (C)
The “____________” consist of 2
nitrogenous ___________ joined
together in the middle by
_____________________ bonds
____________________ (G)
These bases are the “letters” that
spell out the _________________
code
Ms. Bruno
DNA
Regents Biology
Base Pairing:
__________ bases (a pair) make up
each “___________” of the DNA ladder
In base pairing:
Adenine always pairs with
_________________ (A-T)
Cytosine always pairs with
_________________ (C-G)
The Formation of DNA:
To make DNA, ________________________ are joined
together in long, continuous __________________ of
nucleotide building blocks
____________ DNA strands bind
_________________________ to form the “double” helix
The binding of two DNA strands to each other requires
that the bases pair in a very ___________________ and
______________________ manner
Complimentary Strands!
An _______ on one strand means that the _________________
strand must contain a _______ at the same position
ATGCCAATGGGATC
A ________ on one strand means that the opposite strand has a
________at the same ___________________
In this way, the strands are said to be ________________________!
Practice Problem:
A strand of DNA has 100 bases. Thirty-five of these bases are adenine. How many bases are cytosine?
Ms. Bruno
DNA
Regents Biology
DNA Replication:
To _____________________ the genetic material, the two strands of DNA are
_______________________ one base at a time and a __________ strand of DNA is made using the _DNA
literally unwinds and “unzips” along the weak hydrogen bonds that hold the base pairs together
Once the DNA “_____________,” free ______________________ floating in the _____________________
pair with the “free” bases of both DNA strands
Because the ____________________________ bases can only pair in one way
(_____________________________________), two new _________________ strands of DNA are formed
These two new strands are ____________________ to each other and the original DNA molecule strand