DNA Song
(Row, Row, Row your Boat)
I love DNA, made of nucleotides.
Sugar, phosphate, and a base bonded down the sides.
Adenine and Thymine make a lovely pair.
Cytosine without Guanine would be very bare.
**Grab a sheet of paper, and write down this song**
DNA & RNA: The Genetic Codes
DNA Song
(Row, Row, Row your Boat)
I love DNA, made of nucleotides.
Sugar, phosphate, and a base bonded down the sides.
Adenine and Thymine make a lovely pair.
Cytosine without Guanine would be very bare
Recite and Recall
• What cell organelle is the “control center” of
the cell?
• Where is DNA found in the cell?
• What is the function of DNA?
Recite and Recall
• What cell organelle is the “control center” of
the cell?
nucleus
• Where is DNA found in the cell?
Inside the chromosomes in the nucleus
• What is the function of DNA?
give instructions to cell
What is DNA?
• DNA stands for deoxyribonucleic acid.
(de – oxy – ri – bo – nucleic acid)
• DNA is found in the chromosomes that are
located within the nucleus of each cell
• Chromosomes: rod-like structures that
contain genetic material within the nucleus of
a cell.
What is DNA?
Nucleus
has
Chromosomes
made of
Chromatin
made of
DNA
History of DNA
• In 1952, scientist Rosalind Franklin discovered
that DNA is two chains of molecules in a spiral
form.
• By using an X-ray technique, Dr. Franklin
showed that the large spiral was probably
made up of two spirals.
• In 1953, scientists James Watson and Francis
Crick made a model of a DNA molecule.
DNA Structure
• DNA has 2 strands that form a double helix, or
“twisted ladder”
• DNA is made up of smaller unit called
nucleotides.
• A nucleotide is made up of 3 parts:
– Deoxyribose sugar
– Phosphate
– Nitrogen base
DNA is named deoxyribonucleic
acid, because it is made of the
sugar, deoxyribose!
Nucleotide
DNA Structure
• The sides, “backbone”
of DNA are made of
the sugar,
deoxyribose, and the
phosphates.
• Color the deoxyribose
blue
• Color the phosphates
pink
DNA Structure
• The rungs in the middle of the DNA “twisted
ladder” are made of the nitrogen bases.
– Adenine, (A)
ALWAYS pair up!
– Thymine (T)
– Guanine (G)
ALWAYS pair up!
– Cytosine (C)
• The bases are bonded together by
hydrogen bonds.
Color the DNA
Structure.
DNA Structure
Match the bases with their pairs.
•
•
•
•
•
•
•
•
A
G
C
G
T
T
A
C
Match the bases with their pairs.
•
•
•
•
•
•
•
•
A
G
C
G
T
T
A
C
• T
•C
•G
•C
•A
•A
• T
•G
Questions
1. Why is the nucleus called the “control
center” of the cell?
3. Where in the cell are chromosomes located?
4. DNA can be found in what organelles?
5. What two scientists established the structure
of DNA?
Questions
1. Why is the nucleus called the “control center” of
the cell? It tells the cell what to do
3. Where in the cell are chromosomes located?
nucleus
4. DNA can be found in what organelles?
mitochondria, chloroplasts
5. What two scientists established the structure of
DNA?
Watson & Crick
Questions
7. What are the sides of the DNA ladder made
of?
8. What 3 parts make up a single nucleotide:
9. What are the 4 bases that make up the rungs
of the DNA ladder?
10. What sugar is found in DNA?
11. How do the bases bond together?
A bonds with ______
G bonds with______
Questions
7. What are the sides of the DNA ladder made of?
Sugar and phosphates
8. What 3 parts make up a single nucleotide:
sugar, phosphate, nitrogen base
9. What are the 4 bases that make up the rungs of the
DNA ladder?
Adenine, thymine, guanine, cytosine
10. What sugar is found in DNA? deoxyribose
11. How do the bases bond together?
A bonds with __T__
G bonds with__C___
RNA Structure
• RNA is known as ribonucleic acid, a singlestranded nucleic acid.
• RNA is made of nucleotides:
– Ribose sugar
– Phosphate
– Nitrogen base (Adenine, Guanine, Cytosine,
Uracil)
Color the RNA
Structure.
Compare DNA Vs. RNA
Deoxribose
sugar
Nucleic acid
Adenine
Double
stranded
Guanine
Phosphate
Ribose sugar
Single stranded
Cytosine
Uracil
Thymine
RNA Structure
• There are 3 types of RNA:
– mRNA (messenger RNA)
– tRNA (transfer RNA)
– rRNA (ribosomal RNA)
3 Types of RNA
• mRNA, is the RNA strand that is coded directly
from a DNA strand.
• Its job is to travel out of the nucleus to the
ribosome (rRNA) in the cytoplasm.
• There it gets decoded so that tRNA can bring
amino acids to the ribosome to build a protein
• This process is known as PROTEIN SYNTHESIS.
How does DNA & the nucleus tell the cell
what to do?
• DNA is condensed into threadlike structures
called chromatin.
• The chromatin is condensed into rodlike
structures called chromosomes.
• Chromosomes are composed of genes,
segments of DNA that code for amino acids.
– These amino acids build proteins that express
certain traits such as blue eyes, or baldness.
• Genes can only be expressed when they have
been turned into a protein.
From DNA – RNA - Protein
• The process of a DNA strand being coded into
a RNA, and then coded into a protein is known
as protein synthesis.
– Step 1: Copy DNA strand (replication)
– Step 2: Turn DNA strand into RNA strand
– Step 3: mRNA carries RNA strand to ribosome
– Step 4: tRNA brings amino acids to ribosome
– Step 5: proteins are made in ribosome
Step 1: DNA copies itself (Replication)
• DNA unzips to form 2 separate strands
• Nitrogen bases pair up to form new strands
• DNA the zips back together.
– Have one old strand and one new strand together.
– This process is called semi-conservative, because
DNA “saves” one old strand and copies one new
strand.
•Color old strand RED
•Color new strand GREEN
DNA Replication
Color the old strand (including its base) red.
Color the new strand (including its base) green.
DNA Replication
Color:
Phosphate
Sugar
Adenine
Thymine
Cytosine
Guanine
Step 2: DNA strand gets coded into
RNA
• DNA unzips
• One side of DNA stranded gets coded for a
mRNA strand
– A to U
– G to C
• DNA the zips back together.
• mRNA travels out of the nucleus.
Step 3: mRNA leaves nucleus and
travels to ribosome in the cytoplasm
Step 4: tRNA brings amino acids to
ribosome
Step 5: Amino acids link to build a
protein
Questions
2. What is a gene?
6. Replication is called “semi-conservative”
because half of the original strand is ______?
10. What sugar is found in RNA?
11. Why is RNA necessary to act as a
messenger?
Questions
2. What is a gene?
section of DNA, codes for a trait
6. Replication is called “semi-conservative”
because half of the original strand is saved.
10. What sugar is found in RNA? ribose
11. Why is RNA necessary to act as a
messenger? DNA does not leave the nucleus;
Double stranded DNA to big to fit through
nuclear pores.
Questions
13. Proteins are made where in the cell?
14. How is RNA different from DNA? ( 3 things)
15. The process of copying DNA is called _____?
16. What is the shape of DNA?
Questions
13. Proteins are made where in the cell?
ribosomes in the cytoplasm
14. How is RNA different from DNA? ( 3 things)
single-stranded, uracil nitrogen base, ribose
sugar
15. The process of copying DNA is called
replication.
16. What is the shape of DNA? Double helix,
“twisted ladder”
Questions
17. How does one cell become a brain cell and
another a skin cell?
18. Why is DNA called the “Blueprint of Life”?
Questions
17. How does one cell become a brain cell and
another a skin cell?
only some genes are turned on
18. Why is DNA called the “Blueprint of Life”?
DNA gives instructions for building an organism.
DNA Helpful websites
• http://learn.genetics.utah.edu/content/begin/dna/
• http://learn.genetics.utah.edu/content/begin/dna/tr
anscribe/
• http://www.pbs.org/wgbh/aso/tryit/dna/#
• http://www.dnalc.org/view/15890-Ribosome-gameinteractive-2D-animation.html
• http://www.mochigames.com/game/proteinsynthesis-race/
• http://www.wisconline.com/Objects/ViewObject.aspx?ID=AP1302