DNA
____--______________________ __________is the last type of __________(contains
carbon and hydrogen) _____________, DNA is a ______________; remember
carbohydrates (CHO, 2H:1O, used for energy), lipids (CHO, lots of H, high energy), and
proteins (CHON, sometimes S) the _________ ____________which is copied and passed
from generation to generation of cells/organisms _______ ____ _____ _____
__________/organisms by having the "code" for enzymes (proteins that are organic
catalysts) DNA is DNA is DNA--all life as we know it contains DNA.
STRUCTURE OF DNA
It is a polymer (______________________________________________) called
nucleotides (for carbohydrates--the________________________, a monosaccharide; for
proteins--the building blocks are amino acids)
Each nucleotides has ___ parts:
1) a _________group (like ATP)
2) a 5-carbon sugar called ____________ (remember -ose)
3) 1 of 4 possible nitrogenous bases (______________); each nucleotide is named after the
nitrogenous base it contains.
Each phosphate connects to a deoxyribose (sugar) in a "chain"
There are two chains in a molecule of DNA; called ___________________ chains. Each
side of the chain is a side of the__________, where the nitrogenous bases are like the steps.
Nitrogenous bases:
____________( )
____________( )
____________( )
____________( )
In DNA, the nitrogenous bases are matched together and held by weak hydrogen bonds.
DNA
adenine to thymine A <---> T
guanine to cytosine G <---> C
So wherever there is an A--adenine____ _____ _________, the other chain must have a
T--thymine. When these chains link together, the ladder twists, forming a
______________ ____________. the double helix shape was discovered by _________
_________ and __________ __________.
This model best explains the actions of genes:
a) ________________ (duplication) during mitosis and meiosis
b) controlling the production of proteins
HOW DNA IS COPIED

DNA maintains continuity (composition, order) by a process called
_____________________ (which means duplication)

replication occurs during mitosis and meiosis during interphase; when
chromosomes double
Here's how:

1) the DNA "______________" or "____________" between the
nitrogenous base pairs (breaks the hydrogen bonds)

2) free nucleotides ___________ in the nucleus __________ up according to
the following pattern:
A with T
T with A
C with G
G with C
This occurs until all of the DNA is copied to form ____ double helices.
THE GENETIC CODE
Each strand of DNA has about ___ ___________ nucleotides which code for proteins
The building blocks of proteins are __________ __________. Every ___ nucleotides
code for an amino acid; this is called a ___________ (found on mRNA)
TAGCTTAAACGT
there are ___ codons above
DNA

different combinations of nucleotides code for different amino acids

to make proteins, we must first make RNA in the nucleus
DIFFERENT CODES (CODONS) FOR DIFFERENT AMINO ACIDS
RNA--Ribonucleic Acid
Ribonucleic acid (______) is a lot like deoxyribonucleic acid (it is made up of 3-part
nucleotides), but there are ____ differences:
1) RNA has _________ as the sugar instead of _________________
2) has _______ chain--not a double helix
3) has _____________ (U) instead of _______________ (T)
There are also ____ different kinds of RNA.
______(____________________)- "copies" and "carries" the genetic code out from the
nucleus; only one strand!
_____ (_____________________)- the framework for the ribosomes, which synthesize
proteins.
______(_____________________)- transports amino acids from the cytoplasm to the
ribosomes to build proteins
PROTEIN SYNTHESIS: TRANSCRIPTION AND TRANSLATION
DNA
TRANSCRIPTION

the process of making __________ from _______

_______ is a template for the production of _________

this occurs in the ____________ ONLY!
1) first, the _______ must be "unzipped" (just like replication)
2) then, in the nucleus, free RNA nucleotides _______ _____ with the template
DNA in this pattern:
DNA RNA
A -----> ___
C -----> ___
G -----> ___
T -----> ___
3) The now formed ___________ strand of mRNA now carries the __________
________ and _________ the nucleus to the __________ in the _____________; the
DNA "re-zips" back up to the double helix
The code must now be changed into a protein...it must be TRANSLATED into a
protein.
TRANSLATION
1) the mRNA from _______________ in the nucleus, then moves to the
______________; DNA __________ leaves the nucleus!
2) mRNA __________ up with the ribosomes (which are made up of __________ ), the
protein factory
3) tRNA brings _________ _________ to the ribosome from the _______________
and matches them up to the ________; the _______ matches up with the mRNA--the
__________ on the mRNA links up with the __________ on the _________;
4) each new ___________ ___________is bonded to the others by dehydration
synthesis, forming a chain of amino acids--a __________________ (remember the
peptide bond is formed between amino acids)
DNA
GENE:

a section of ________ that has the code for _______ polypeptide

proteins are made up of ______ or ________ polypeptides (like hemoglobin)

so, ________ make proteins by holding the code for polypeptides

the way the _____________ fold together determines the ___________ of the
protein

if a _____________protein is needed by the organism, the stretch of DNA that
holds the polypeptides for that protein get______________ _____; when not
needed, it is __________ _______.
GENE MUTATION
So, a gene _____________ (like the one that causes polydactyly, sickle-cell anemia,
Tay Sachs, PKU) is when the __________ sequence (A,T,C,G) of DNA is altered...
...which __________ the mRNA codon during transcription...
...which codes for the _________ amino acid...
...which produces an ____________ protein!!!
Gene mutations are caused by _______________ ____________(mutagens).
DNA & INDIVIDUALITY
DNA codes for proteins
Some sequences are the __________ for mostly everyone (hemoglobin, blood antigen
A, ribosomal rRNA). Some are ____________ (eye color, nose shape, different
enzymes).
THESE DIFFERENCES MAKE YOU WHO YOU ARE!!!
GENETIC ENGINEERING
DNA
Because DNA is the same for all organisms, the DNA of one organism can be
"_______ _____ ________" into the DNA of another organism. The organism who
received this sequence of DNA will __________this code! By using genetic
engineering, we have been able to _____________ important chemicals such as insulin,
interferon (a cancer fighting protein), and human growth hormone (GH) in large
quantities in bacteria! You can also ____________ the genome of organisms to
possibly __________ genetic defects or agriculturally desirable plants and animals.
Recombinant DNA
Recombinant DNA is ___________ DNA strands that is produced when a small piece
of DNA is _________ to the genome (DNA molecule) of another organism. It will
_____________ the polypeptide (protein) it codes for. Organisms that contain
recombinant DNA are called __________________ _____________________.
_________________ _______________ can "cut" specific pieces of the DNA molecule
(ex. AATT); also called called ________ ___________. Other enzymes can "paste" the
DNA back together.
Here's an example how...
1) restriction enzymes are used to "_______" certain sequences of DNA
2) genes that are _______________ (ex. the insulin gene) can be removed from the cut
sequences
3) other restriction enzymes can cut _______________ (circular DNA in bacteria; acts
as a vector--carrier of DNA) or ________ strands in another organism
4) then certain enzymes can "________" the genes you want into the plasmid or other
organism
5) the ________ can be _____________ and now contains the recombinant DNA,
which will _____________ the polypeptide it codes for!
DNA