21DNA and RNAPicture of how DNA is used by our body:
22DNA and RNAPicture of how DNA is used by our body:
23DNA and RNAPicture of how DNA is used by our body:
24Background: DNA RNA Protein Where is DNA Stored?________________What organelle makes proteins?__________If this is so, where are proteins made? ____________What problem does this pose? ___________________________________________nucleusribosomescytoplasmDNACannot leave the nucleus to give directions to ribosomes.
25Background: 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.
26RNARNA’s structure is very similar to the structure of DNA except for 3 major differences.
34Background: DNA RNA Protein What is a protein? _______________________Long chains of amino acids
35What 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)
36Background: DNA RNA Protein DNA can not _______________________DNA contains the directions to make ____________Proteins can only be made in the ____________ by _______________Leave the nucleusproteincytoplasmribosomes
37Background: DNA RNA Protein What problem does this cause?DNA cannot leave the nucleus to give directions to ribosomes.
38Background: 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!
39Making a disposable copy (mRNA) from DNA. TranscriptionTranscription:Making a disposable copy (mRNA) from DNA.
40RNA Polymerase opens the DNA strand of one gene (example: keratin) TranscriptionDescription Step 1:RNA Polymerase opens the DNA strand of one gene (example: keratin)
46Transcription 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 TmRNA U A G G C U U C A C U A
47Transcription 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.
48Transcription 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:codonProline, valine, isoleucine, tryptophan
49Making protein from mRNA. TranslationTranslation:Making protein from mRNA.
50mRNA leaves the nucleus to find a ribosome. TranslationDescription Step 1:mRNA leaves the nucleus to find a ribosome.
58Translation Questions How does the ribosome know where to start reading mRNA?There is a universal start codon AUG, which codes for Methionine
59Translation Questions How does the ribosome know where to stop reading the mRNA?Stop codons
60Translation 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.
62Structure of DNA: A T C G complimentary bases ____ always pairs with ____, and____ always pairs with ____.The bases that pair with each other are called _____________________.CGcomplimentary bases
63Structure of DNA: Categories Purines Pyrimidines Examples: Drawing: Nitrogen Bases can be separated into two different categories:CategoriesPurinesPyrimidinesExamples:Drawing:GuanineThymineAdenineCytosine
64Structure of DNA: thousands protein gene 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 ______.thousandsproteingene
65Structure of DNA: histones chromatin chromosomes In your cells, DNA wraps tightly around proteins called ___________ to produce a substance called ___________ which condenses during cell division (mitosis) to form structures called _______________.histoneschromatinchromosomes
66Structure of DNA: A segment of DNA that codes for a specific protein What is a gene: _______________________________________________.A segment of DNA thatcodes for a specific protein
67What 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)