dna: life's code
DESCRIPTION
DNA: life's code. =. DNA KEY TERMS. DNA NITROGEN BASE NUCLEOTIDE REPLICATION SYNTHESIS RNA DOUBLE HELIX MUTATION POINT MUTATION FRAMESHIFT MUTATION CHROMOSOMAL MUTATION TRANSLOCATION. CLONES FRATERNAL TWINS IDENTICAL TWINS TRANSCRIPTION TRANSLATION PROTEIN PROTEIN SYNTHESIS - PowerPoint PPT PresentationTRANSCRIPT
DNA KEY TERMS• DNA• NITROGEN BASE• NUCLEOTIDE• REPLICATION• SYNTHESIS• RNA• DOUBLE HELIX• MUTATION• POINT MUTATION• FRAMESHIFT MUTATION• CHROMOSOMAL MUTATION• TRANSLOCATION
• CLONES• FRATERNAL TWINS• IDENTICAL TWINS• TRANSCRIPTION• TRANSLATION• PROTEIN• PROTEIN SYNTHESIS• INTERPHASE• SEMI-CONSERVATIVE
REPLICATION
DNA ANCHORS AND BENCHMARKS
• Describe how the process of DNA replication results in the transmission and/or conservation of genetic information.
• Explain the functional relationships between DNA, genes, alleles, and chromosomes and their roles in inheritance.
• Describe how the processes of transcription are similar in all organisms.
• Describe how genetic mutations alter the DNA sequence and may or may not affect phenotype, (e.g.: silent, nonsense, frameshift)
• Explain how genetic engineering has impacted the fields of medicine, forensics, and agriculture (e.g., selective breeding, gene splicing, cloning, genetically modified organisms, gene therapy).
Process Box-Type 1
Why do we use models? Explain at least TWO purposes of models.
Model Making Activity and Question Sheet
Process Box-Type 1Recall the models of DNA you made. List the following:3 parts that were included in your model1.2.3.2 types of bonds1.2.2 rules/’laws’ of the “N’s”.1.2.1 thing you learned about DNA other than what is above.1.
DNA makes up genes that determines the ______ of all living things….such as:
traits
Eye color, skin color, texture, freckles, hair color, style…etc
DNA =
Deoxyribo-Nucleic Acid
Makes up _____________
Controls ____________
Forms _______________________
Found in the __________ of all cells
GENES
TRAITS
CHROMOSOMES
NUCLEUS
DNA is composed of four types of NUCLEOTIDES.
• DNA is made up of a long chain of nucleotides.• Each nucleotide has three parts.
1) a phosphate group2) a deoxyribose sugar3) a nitrogen-containing base
phosphate group
deoxyribose (sugar)
nitrogen-containingbase
The code is found in the
“________” of the ladder.
Each rung is a combination of ________________ bonded together.
The Nitrogen bases are:
C = CYTOSINE
G = GUANINE
T = THYMINE
A = ADENINE
RUNGS
2 nitrogen bases
TA
CG
Nucleotides always pair in the same way.
• The base-pairing rules show how nucleotides always pair up in DNA.
• Because a pyrimidine (single ring) pairs with a purine (double ring), the helix has a uniform width.
“A” bonds ONLY with “___”
“C” bonds ONLY with “___”
This goes on for the entire length of the DNA molecule, which consists of __________ of nitrogen bases.
BILLIONS
CG T
A
C G
CG
CG
CG
TA
TA
TA
TA
T
G
Process Box- Type 1 ReviewBelow are some words/terms that you have recently encountered in the course. Next to each word, write a couple of thoughts that relate to each term.
1. Nucleotides- ______________________________2. 4-_______________________________________3. Billions-__________________________________4. Rung-____________________________________5. Gene-____________________________________
Process Box-Type 1
Think back: What type of organic compounds do nucleotides make up? Are they monomers or polymers?
The ____________________ in DNA will determine what the trait is.
“O W L” meansIf you change the letters to
“L O W”
it no longer means…However…
For example: Lets take a look at the letters of the alphabet…
SEQUENCE OF LETTERS
“A predatory bird”
“A predatory bird”
WON – NOWGOD – DOGANT – TANBAT – TABDNA – DANADD – DADTAR – RATEAR – ARETWO – TOWEAT - ATESAW – WAS
Since DNA consists of billions of nitrogenous base pairings, the amount of variation among organisms is HUGE.
If you change only one letter, the entire code will be changed, and therefore the organism will be different!!
Process Box-Type 1It’s all about the numbers.Match the correct number to the correct phrase. 4 30,000 1,000,000,000+
______________ - base pairings______________ - nitrogen bases______________ - genes
•DNA makes up a _______________.
•Chromosomes are found in the nucleus of every cell in the body!!
CHROMOSOME
A gene is a
___________________that codes for a _____________.
There are about __________ genes in an entire DNA molecule
geneSMALL PIECE OF DNA
Specific trait
30,000
1. What does DNA mean? _____________________________________
2. Suppose one side of a DNA molecule had the bases
A-A-G-T-C- G- A-T-G-G-C-A-C-C. What would the other side of the DNA look like? ____________________________________________
3. What is the function of RNA? _____________________________
4. What is a mutation? ______________________________________
5. What term best describes what a DNA looks like? _________________
6. Explain the relationship between DNA, chromosomes, and genes?
__________________________________________________________
7. If everyone consists of only 4 nitrogen bases (A-T-C-G), why are no two people alike? __________________________________
8. How many chromosomes does a human have? ___________
9. How many genes does a human have? ___________
10. Therefore, approximately how many genes are on a single chromosome? ______
11. If 24% of a DNA molecule is Adenine, what percent would be…
Thymine = ____% Guanine= _____% Cytosine= _____%
If there is 37% of Adenine in a DNA molecule…
How much Thymine? ___________How much Cytosine? ___________How much Guanine? ___________
If there is 23% of Guanine in a DNA molecule…
How much Thymine? ___________How much Cytosine? ___________How much Adenine? ___________
If there is 18% of Cytosine in a DNA molecule, which is the only possibility for another nitrogen base? (Put an ‘X’ on your answer)
________18% Adenine________64% Adenine________ 32% Guanine________ 32% Thymine
UNDERSTANDING THE COMPONENTS OF DNA
Process Box-Type 1You were exposed to a similar graph earlier in the year. Study the graph. Write down a list of at least FOUR things you can recall about the graph. Your statements should be written as complete thoughts.
Replication makes an exact copy of a cell’s DNA • A single strand of DNA serves as a template for a new strand.• The rules of base pairing direct
replication.• DNA is replicated during the
____________stage of thecell cycle.
• Each body cell gets acomplete set ofidentical DNA.
• DNA replication takes place in ___________Nucleus
S (synthesis)
REPLICATION
Proteins carry out the process of replication. • DNA serves only as a template. • Enzymes and other proteins do the actual work of
replication.– Enzymes unzip the _______________– Free-floating nucleotides form hydrogen bonds with the
template strand. nucleotide
The DNA molecule unzips in both directions.
Double helix
BuildDNA
REPLICATION
Process Box-Type 1General Word Dissection.Break down these words and define them in your own words. Then write an instance when each one may occur.
What is it? When does it happen?Replication:Transcription:Translation:
RNA carries DNA’s instructions.
• The central dogma states that information flows in one direction from _____________
______________DNA to RNA toprotein
• The central dogma includes three processes.
• RNA is a link between DNA and proteins.
replication
transcription
translation
1) Replication
2) Transcription
3) Translation
RNA differs from DNA in three major ways.
1)RNA has a ____________________
2)RNA has ___________ instead of thymine.
3)RNA is a __________________________.
Ribose sugar
uracil
single-stranded structure
TRANSCRIPTION
The transcription process is similar to replication. • Transcription and replication both involve complex enzymes
and complementary base pairing.
• The two processes have different end results.
– REPLICATION copiesthe ENTIRE________ molecule;TRANSCRIPTION copiesonly part of the DNA molecule-
copies only a specific ___________.– Replication makes
_______ copy; transcription can make ________copies.
growing RNA strands
DNA
onegene
DNA
gene
onemany
TRANSCRIPTION
Amino acids are coded by mRNA base sequences. • Translation converts mRNA messages into polypeptides.• A codon is a sequence of three nucleotides that codes for an
amino acid.
codon formethionine (Met)
codon forleucine (Leu)
TRANSLATION
• For translation to begin, tRNA binds to a start codon and signals the ribosome to assemble.
– A complementary tRNA molecule binds to the exposed codon, bringing its amino acid close to the first amino acid.
TRANSLATION
– The ribosome helps form a polypeptide bond between the amino acids.
– The ribosome pulls the mRNA strand the length of one codon.
TRANSLATION
– The now empty tRNA molecule exits the ribosome.– A complementary tRNA molecule binds to the next
exposed codon.– Once the stop codon is reached, the ribosome
releases the protein and disassembles.
TRANSLATION
(Physical trait)
RIBOSOMENUCLEUS
RNA is a “__________” molecule. It helps carry the DNA code to the __________ so it can make the protein.
Skin color/texture
Eye color/shape
Height
Bone density
Hair texture
Etc…
DNA contains the code for what protein will be made by the cell
HELPER
RIBOSOME
•When the sequence of letters is changed. Since the code no longer reads the correct way, the cell does not make the correct protein.
•Consequently, a different trait may appear.
•They are usually _________
Oops!!
bad
Some mutations affect a single gene, while others affect an entire chromosome.
• A mutation is _______________________________.• Many kinds of mutations can occur, especially during
replication.– POINT MUTATIONS– FRAME SHIFT MUTATIONS– CHROMOSOMAL MUTATIONS
• TRANSLOCATION MUTATIONS
A CHANGE IN AN ORGANISM’S DNA
• Many kinds of mutations can occur, especially during replication.
– A frameshift mutation inserts or deletes a nucleotide in the DNA sequence.
FRAMESHIFT MUTATIONS
• Chromosomal mutations affect many genes.• Chromosomal mutations may occur during crossing over
– Chromosomal mutations affect many genes.– Gene duplication results from unequal crossing over.
CHROMOSOMAL MUTATIONS
A MUTATION is any _________________ in copying the DNA message.
CHANGE = WRONG ______________
A wrong base in the DNA gives the cell the wrong __________________.
If a cell has the wrong message, the wrong type of ________________ is made.
If the wrong protein is made, the wrong ________________ may appear.
CHANGE
BASE PAIR
MESSAGE
PROTEIN TRAIT
Process Box-Type 1
You recently learned about the different type of mutations that could occur. Now write down AT LEAST TWO different reasons why mutations would/could occur.
Mutations can be caused by several factors.
• Replication errors can cause mutations.
• Mutagens, such as UV ray and chemicals, can cause mutations.
• Some cancer drugs use mutagenic properties to kill cancer cells.
1. Simple copying mistakes during cell reproduction
1. A mutation causes a change in an offspring’s traits only when it takes place in the ___________________ sex cells.
2. Chemicals
1. _______________
2. _______________
3. Radiation
1. _______________
2. _______________
__________________: Any agent that can cause alterations to DNA
PARENTS
NICOTINE
ASBESTOS
SUN
X-RAY
MUTAGEN
HELPFUL MUTATIONSHARMFUL MUTATIONS
Any trait that interferes with the ______________________
and _________________ of an organism.
Any trait that enhances an organisms ability to______________________
and _________________ in its _____________________.
REPRODUCTION
SURVIVAL
REPRODUCE
SURVIVE ENVIRONMENT
1. The term “clone” refers to organisms having ____________________
Two “clones” are exact _______________ of each other.
Same _______ = Same __________ = Same _________
2. Examples of clones:
a. _________________: form from the splitting of _____ fertilized egg
b. Clone organisms produced in ___________________
IDENTICAL DNA
copies
DNA GENES TRAITS
IDENTICAL TWINS ONE
LABORATORY
Fraternal Twins vs Identical Twins_____________________ eggs are fertilized by_____________________ sperm.
Each egg and sperm carry __________________combinations of ____________.
Therefore, each offspring will ________________genetically.
TWO DIFFERENT
TWO DIFFERENT
DIFFERENTDNA
VARY
10
20
20
20
20
20
10
RemoveUnfertilized
Ovum
Destroy Nucleus
RemoveBody Cells
Insert Nucleus from Dark frog into egg
of Light frog
DNA MOLECULE
_______________(SHAPE)
SIDE PARTS RUNG PARTS
___________ ___________
___________
& ___________
___________ ___________
WHAT IS THE DIFFERENCE BETWEEN…
Cell: ________________________________
Nucleus: ________________________________
Chromosome: _________________________________
Gene(s): _____________________________________
DNA: ________________________________________
How are they related? ____________________________________________________________________________
TYPE II’SIf you were to observe your DNA molecule and compare it to another person’s DNA, what is one thing that you’d expect to find in common?What is one thing you’d expect to be different?
Process Box-Type 2
Explain what all DNA has in common and then describe how DNA differs. Give examples of both.
Process Box-Type 2Describe the components of a nucleotide using these terms: nitrogenous base, deoxyribose sugar, phosphate, double helix, sides, rungs.
1. What does DNA mean? _____________________________________
2. Suppose one side of a DNA molecule had the bases
A-A-G-T-C- G- A-T-G-G-C-A-C-C. What would the other side of the DNA look like? ____________________________________________
3. What is the function of RNA? _____________________________
4. What is a mutation? ______________________________________
5. What term best describes what a DNA looks like? _________________
6. Explain the relationship between DNA, chromosomes, and genes?
__________________________________________________________
7. If everyone consists of only 4 nitrogen bases (A-T-C-G), why are no two people alike? __________________________________
8. How many chromosomes does a human have? ___________
9. How many genes does a human have? ___________
10. Therefore, approximately how many genes are on a single chromosome? ______
11. If 24% of a DNA molecule is Adenine, what percent would be…
Thymine = ____% Guanine= _____% Cytosine= _____%
Deoxyribo-nucleic acid
T- T- C- A- G-C--T- A- C- C- G-T- G-Gcarry the DNA code to the ribosome
A random change in the DNA code
Double helix
A chromosomes is made up of DNA, which is consists of about 30,000 genes
bc it’s the sequence of nitogen bases that makes us different46
About 30,000
~ 650
24 26 26
Process Box-Type 2
Describe where AND when replication occurs versus where AND when transcription occurs.