DNA: Replication Transcription Translation. Fill in the missing bases: A T G G A C T C G G AA G T T...
Transcript of DNA: Replication Transcription Translation. Fill in the missing bases: A T G G A C T C G G AA G T T...
DNA:ReplicationTranscriptionTranslation
Fill in the missing bases:
A T G G A C T C G G AA G T
T A C C T G A G C C T T C A
What do the letters of DNA stand for?
•A = ______________Adenine
•T = ______________Thymine
•G = ______________Guanine
•C = ______________Cytosine
Structure of DNA:
•Who are the two scientists credited with discovering DNA: _________________ and ________________
James WatsonFrancis Crick
Structure of DNA:
•What is the DNA “backbone” made of? _________________sugar and phosphate
Structure of DNA:
•What are the three parts of a nucleotide?
Structure of DNA:
•What does DNA stand for? ____________________
•Sugar =
Deoxyribose•Macromolecule =
Nucleic Acid
Deoxyribonucleic Acid
DNA Replication
•What is DNA Replication?
A process in your cell that makes a copy of your DNA before mitosis.
DNA Replication
•Why is DNA Replication important for cells and multicellular organisms?
Every time a cell divides you need each new cell to have a complete set of DNA.
DNA Replication
•When does DNA Replication occur?
During S phase of interphase, before mitosis.
DNA Replication
•What is a chromosome?
Tightly wound DNA
DNA Replication
•What is DNA Polymerase?
An enzyme that copies DNA by matching complimentary nucleotides to the original DNA strand.
DNA Replication STEP 1
•DNA Polymerase breaks Hydrogen bonds of double helix apart. DNA
DNA Replication STEP 2
•DNA Polymerase matches nucleotides to complementary bases.
DNA
T
TAGT
DNA Replication STEP 3
•Two identical copies of DNA are formed.
DNA Replication
•DNA replication is considered ‘semi-conservative’.
•“Semi” means: •“Conservative” means:
HalfSave
DNA Replication
•How is DNA replication semi-conservative? Explain in your own words!
DNA Replication
•Draw a picture of a chromosome without DNA replication, and one with DNA replication.
DNA and RNA
•Why do we need DNA in the first place?DNA has the instructions for every protein our body is made of
Chromosome before/after replication
DNA and RNA•Picture of how DNA is used by our body:
DNA and RNA
•Picture of how DNA is used by our body:
DNA and RNA
•Picture of how DNA is used by our body:
Background: DNA RNA Protein
•Where is DNA Stored?________________•What organelle makes proteins?__________
•If this is so, where are proteins made? ____________
•What problem does this pose? ___________ ________________________________ ________________________________
nucleusribosomes
cytoplasmDNA
Cannot leave the nucleus to give directions to ribosomes.
Background: DNA RNA Protein
•How does RNA solve this problem?RNA is a disposable copy of DNA that can leave the nucleus and travel to ribosomes.
RNA
•RNA’s structure is very similar to the structure of DNA except for 3 major differences.
DNASugar: Deoxyribose
RNA Sugar: Ribose
ribose sugar
DNADouble Stranded
RNA Single Stranded
DNABases:ATCG
RNA Bases: AUCG
ribose sugar
Thymine
Uracil
Full Name Messenger RNA
Short Name mRNA
Drawing
Full Name Transfer RNA
Short Name tRNA
Drawing
Full Name Ribosomal RNA
Short Name rRNA
DrawingRIBOSOME
Background: DNA RNA Protein
Background: DNA RNA Protein
•What is a protein? _______________________Long chains of amino acids
•What are some examples of proteins?Make up all your traits – hair type and color (keratin), what color your skin is (melanin), what enzymes you have to break down food (lactase, peroxidase, amylase), how strong you are (actin/myosin)
Background: DNA RNA Protein
•DNA can not _______________________•DNA contains the directions to make ____________
•Proteins can only be made in the ____________ by _______________
Leave the nucleus
protein
cytoplasm ribosomes
Background: DNA RNA Protein
•What problem does this cause?
DNA cannot leave the nucleus to give directions to ribosomes.
Background: DNA RNA Protein
•How does RNA solve this problem?
mRNA is a disposable copy of DNA that can leave the nucleus to go meet up with the ribosome!
Transcription
•Transcription:
Making a disposable copy (mRNA) from DNA.
Transcription
•Description Step 1:
RNA Polymerase opens the DNA strand of one gene (example: keratin)
Transcription
•Diagram Step 1:
Transcription
•Description Step 2:
RNA Polymerase matches complimentary bases to original DNA strand.
Transcription
•Diagram Step 2:
Transcription
•Description Step 3:
RNA Polymerase is finished, mRNA leaves the nucleus and goes to ribosome.
Transcription
•Diagram Step 3:
Transcription practice
•If this was the original DNA nucleotide strand, what would the mRNA copy look like?
•DNA: A T C C G A A G T G A T
•mRNA U A G G C U U C A C U A
Transcription Questions
•What does RNA polymerase do?
•Does RNA polymerase copy every gene in the nucleus? _______ Why?
Make a copy of DNA called mRNA.
NoIt only needs the piece of DNA (gene) that codes for the protein the cell needs.
Transcription Questions
•Just like we read several letters together to have meaning as words, a cell reads three bases together as a code for an amino acid (one part of a protein): Every three bases is called a:
•Examples:
codon
Proline, valine, isoleucine, tryptophan
Translation
•Translation:
Making protein from mRNA.
Translation
•Description Step 1:
mRNA leaves the nucleus to find a ribosome.
Translation
•Diagram Step 1:
Translation
•Description Step 2:
A tRNA that matches the mRNA sequence clicks into place.
Translation
•Diagram Step 2:
Translation
•Description Step 3:
The amino acids are linked together by a peptide bond.
Translation
•Diagram Step 3:Peptide bond
Translation
•Description Step 4:
Amino acid chain breaks off, folds up, and is ready to use.
Translation
•Diagram Step 4:
Translation Questions
•How does the ribosome know where to start reading mRNA?
There is a universal start codon AUG, which codes for Methionine
Translation Questions
•How does the ribosome know where to stop reading the mRNA?
Stop codons
Translation Questions
•After tRNA has released its amino acid, where does it get another amino acid?
When an organism eats food with protein, proteins are broken down into amino acids, which are then used to build more protein.
End IS
Structure of DNA:
•____ always pairs with ____, and •____ always pairs with ____.•The bases that pair with each other are
called _____________________.
A TC G
complimentary bases
Structure of DNA:
•Nitrogen Bases can be separated into two different categories:
Categories Purines Pyrimidines
Examples:
Drawing:
GuanineAdenine
Thymine
Cytosine
Structure of DNA:
•A single DNA molecule may contain ____________ of nucleotides (AKA: bases)
•The order of the nucleotides (bases) in a DNA is a code that provides instructions for making ____________. A segment of DNA that codes for a specific protein is called a ______.
thousands
proteingene
Structure of DNA:
•In your cells, DNA wraps tightly around proteins called ___________ to produce a substance called ___________ which condenses during cell division (mitosis) to form structures called _______________.
histoneschromatin
chromosomes
Structure of DNA:
•What is a gene: _______________________________________________.
A segment of DNA that codes for a specific protein
•What do proteins do?Make up all your traits – hair type and color (keratin), what color your skin is (melanin), what enzymes you have to break down food (lactase, peroxidase, amylase), how strong you are (actin/myosin)