Unit 7 Review Test tomorrow

1. Structure of genetic info What is the central dogma of genetic information? DNA  RNA  Protein What are the Chargaff rules? A = T ; G = C What is a nucleotide, what is it used for? The monomer that makes up DNA/RNA d. What does DNA stand for? Deoxyribonucleic acid What does RNA stand for? Ribonucleic Acid

1. Structure of genetic info Describe the structures of DNA and RNA DNA = double helix, double stranded twisted ladder, long RNA = single stranded, half of DNA, shorter What are the different purposes for DNA and RNA? DNA = contains copy of all original info for cells RNA = temporary/shorter strand makes copies of genes What is a codon? 3 letter “code” that makes a particular amino acid What does a “complementary” strand of DNA or RNA mean? The attached that appropriately bonds to that molecule. EX: A pair to T, G pairs to C, A pairs to U.

2. DNA Replication What does primase do? Places an RNA primer to a copies section of DNA What does polymerase do? Places new complementary nucleotides to make new strand of DNA What does helicase do? “Unzips” of opens the DNA double helix What does ligase do? Mends together different new segments of DNA

2. DNA Replication What is the difference between a leading strand and a lagging strand? Leading = copies very quickly Lagging = copies very slowly How is a complementary strand of DNA different from a normal strand? It just pairs to the opposite side, otherwise no difference Describe the process of DNA replication Untwist, unzip, open, lay down primer, add new nucleotides, fix mistakes and bond new pieces, close into helix.

3. Transcription Define transcription Changing DNA into a form of RNA What is the purpose of transcription? To make mRNA to go to ribosomes to make proteins What is mRNA? Messenger RNA Where does this transcripted RNA go? Ribosomes Describe the process of transcription information from DNA is carried via RNA to make proteins

4. Translation Define translation When mRNA is read to assemble polypeptide (amino acids are bonded together to form protein in ribosome) What is the purpose of translation? To assemble amino acids in proper sequence What is tRNA? What is an anti-codon? Transfer RNA. The portion of the tRNA that bonds to mRNA to carry and attach the amino acid.

4. Translation What are introns and exons? Introns – unnecessary sections of DNA for a gene Exons – the required sections of DNA for a gene What does a spliceosome do? How does it relate to translation? Cuts the introns out of RNA. Makes sure only the necessary amino acids are made Describe the process of translation mRNA is read in the rRNA (ribosome), tRNA moves in to drop off amino acids in sequence that matches the message in the mRNA Can you use an mRNA codon chart to find what amino acids are created in translation? Yes, you should. A copy will be available for your use on the test so you may use it

5. Mutations What is a mutation? A change in a sequence of DNA What makes a substitution (point) mutation unique? (Could you identify one?) Only one nucleotide is changed/mutated. What’s the difference between a missense, nonsense, and silent mutation? Missense = changes amino acid, nonsense = makes a stop codon, silent = makes no amino acid change What makes a frameshift mutation unique? (Could you identify one?) A nucleotide is added or deleted, causing all other nucleotides afterwards to match incorrectly.

5. Mutations What’s the difference between a deletion and insertion mutation? deletion = loss of a nucleotide, insertion = adds a nucleotide What makes a chromosomal mutation unique? (Could you identify one?) This can change many genes at once, causing many particular issues at once. Can you identify if a chromosomal mutation is a deletion, duplication, translocation, or inversion? You should know the differences – see class notes

6. Biotechnology a. Biotechnology – defined of a tool/process of altering the genes of an organism in order to produce desired changes. b. Restriction Enzymes – enzymes designed to fragment or cut DNA into smaller portions c. Polymerase Chain Reaction (PCR) – A process used by scientists to artificially make millions of copies of DNA sequences for the purpose of study and research d. Gel Electrophoresis – A process used by scientists to measure the approximate sizes of strands of DNA and compare them with other sizes in other organisms. e. DNA fingerprinting – a common tool used in forensics and biology for comparing evolutionary and paternity in organisms.

ANY QUESTIONS?!