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The human genome of is found where in the human body?. Nucleus Ribosome Smooth ER Cell membrane. The cellular structure where proteins are made is called the. Nucleus Smooth ER Ribosome Cell membrane. DNA and Biotechnology. Announcements. Circulation lab: Due Today!
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The human genome of is found where in the human body? • Nucleus • Ribosome • Smooth ER • Cell membrane
The cellular structure where proteins are made is called the • Nucleus • Smooth ER • Ribosome • Cell membrane
Announcements • Circulation lab: Due Today! • Homework Assignment #2: Due Wednesday! • Textbook Reading: • Chapter 21: Pgs 449-461 • Chapter 19: Pgs 406-412 • Online work: Chapter 21- Due Wednesday!
Lecture Outline • DNA- Structure, function, and importance • How DNA works • The central dogma • Transcription and Translation • The DNA code • DNA replication • PCR- Function, usefulness, how it works • PCR Lab
The DNA double helix is the code of life • The blueprint for all structures in your body which are made of protein • DNA is comprised of nucleotides
Nulceotides are the monomers of nucleic acid polymers • Consist of a sugar, a phosphate, and a nitrogen-containing base • Sugar can be deoxygenated • Bases contain the genetic information
Adenine always matches with Thymine, Cytosine always matches with Guanine-Hydrogen bonds hold bases together
Cellular machinery is sophisticated and required for life Cellular machinery is made largely of proteins Blueprints for all cellular machinery are contained in genes Genes are inherited from parents Humans have ~30,000 genes Living things are extremely complex
Protein variety is generated by 1o structure- the sequence of amino acids which make the protein
Amino Acids • Proteins consist of subunits called amino acids Figure 2.12
How DNA works • Replication • Transcription • Translation
The sequence of DNA bases is the code for the primary structure of proteins
All cells require a copy of the genome • Genome- all the genes of the cell • Human genome is made of DNA • DNA is similar in all cells • Gene- 1 DNA Molecule (+ proteins the genetic information to produce a single product (protein) • DNA replication copies all cellular DNA
Replication of DNA Figure 21.2
In vivo, enzymes such as DNA polymerase make DNA replication happen
Computers use binary digital code • 01100001 = A • 01100010 =B • 01000011 =c • 00100111 = apostrophe • Etc. • http://www.geek-notes.com/tools/17/text-to-binary-translator/ 01000011 01101000 01100101 01100101 01110011 01100101 01100010 01110101 01110010 01100111 01100101 01110010 00100000 01000100 01100101 01101100 01110101 01111000 01100101 = cheeseburger deluxe
How does the DNA code work? • atggcttcctccgaagacgttatcaaagagttcatgcgtttcaaagttcgtatggaaggttccgttaacggtcacgagttcgaaatcgaaggtgaaggtgaaggtcgtccgtacgaaggtacccagaccgctaaactgaaagttaccaaaggtggtccgctgccgttcgcttgggacatcctgtccccgcagttccagtacggttccaaagcttacgttaaacacccggctgacatcccggactacctgaaactgtccttcccggaaggtttcaaatgggaacgtgttatgaacttcgaagacggtggtgttgttaccgttacccaggactcctccctgcaagacggtgagttc=GFP
The DNA code is (nearly) universal It uses groups of 3 bases (codon) 3 bases = 1 codon = 1 amino acid
RNA is ribonucleic acid • Ribose sugar is not deoxygenated • RNA is single-stranded • RNA has Uracil, not Thymine • There are many kinds: mRNA, rRNA, tRNA, siRNA, etc.
RNA can fold back on itself • Single strand offers greater flexibility
Kinds of RNA mRNA tRNA
The Central Dogma of Molecular Biology • DNA RNA Protein • DNARNA : Transcription • RNA Protein: Translation
The Universality of the DNA code makes this possible Firefly gene (Luciferase) in a tobacco plant
DNA Codes for RNA, Which Codes for Protein Figure 21.3
DNA information is transcribed into mRNA Note in DNA: sense strand vs. antisense strand
tRNA’s carry an amino acid at one end, and have an anticodon at the other Amino acid attachment site: Binds to a specific amino acid. Amino acid (phenylalanine) Anticodon: Binds to codon on mRNA, following complementary base-pairing rules. Anticodon mRNA Figure 21.6
The ribosome matches tRNA’s to the mRNA, thereby linking amino acids in sequence
tRNA’s add amino acids one by one according to mRNA instructions until the protein is complete
Proteins are incredibly diverse at the molecular level A few examples Insulin Rubisco ATP synthase Fibrin Nitrogenase Protein function depends greatly on shape
In the DNA code, syntax is critical • THE RED DOG ATE THE BIG CAT • THE RED DOT ATE THE BIG CAT • THG ERE DDO GAT ETH EBI GCA • THR EDD OGA TET HEB IGC AT • THE RED DOG ATE THE BBI GCA T • THE RED RED DOG ATE THE BIG CAT • RED DOG ATE THE BIG CAT
Consequences of a single base substitution • Misshapen protein • Misshapen red blood cell • Clogged capillaries • Cellular damage • Resistance to malaria
Because the DNA code is universal, genes can be moved from one living thing to another Cell with gene of interest Bacterium Step 1: Isolate DNA from two sources. Plasmid Source (donor) DNA Fragments of source DNA Step 2: Cut both DNAs with the same restriction enzyme. Step 3: When mixed, the DNAs recombine by base pairing. Figure 21.14 (1 of 2)
PCR can replicate DNA in vitro 1. dNTPs 2. Mg++ containing Buffer 3. Taq polymerase 4. Primers for your gene of interest 5. Thermal cycler • A gene (piece of DNA) you are interested in All together = DNA xerox machine!
PCR can replicate DNA in vitro • Step 1- Melting • DNA denatures • Step 2- Annealing • Primers bind to complementary sequences • Step 3- Elongation • Taq DNA polymerase adds free nucleotides to strands • Cycle is complete, DNA has doubled • Process can begin again
dNTPs • Individual DNA nucleotides • Four kinds- A, C, G, and T • They match up with template DNA
Taq Polymerase • DNA polymerase isolated from Thermophilus aquaticus bacteria • Lives in hot springs- heat resistant • Optimal Taq temp- 72C
Primers • Single-stranded DNA sequences of 15-30 bp specific to gene of interest • One at the 5’ start, the other at the 3’ end of your gene