Question | Answer |
What is Friedrich Miescher known for? | First to identify DNA as a distinct molecule, called it nuclein, he didn't believe it was the genetic molecule |
Describe Frederick Griffith's experiment and what his major findings were that contributed to the concept of DNA. | Injected mice w/ R-Strain & S-Strain. Mouse w/ S - Strain died, mouse w/ R-Strain lived. Heated up S-Strain to kill harmful bacteria, turned harmless. Then he mixed Dead Bacteria & Harmless bacteria & mouse died. He called this the Transforming Principle. |
What is transformation? | Bacteria taking in DNA and Transforming to another form. |
Describe Oswald Avery's experiment and what his major findings were that contributed to the concept of DNA. | Repeated Griffith's experiment but added. Discovered that DNA is the Transforming Principle. |
Describe Alfred Hershey and Martha Chase's experiment and what his major findings were that contributed to the concept of DNA. | Used radioactive sulfur when the injected to the bacteria it wasn't radioactive . Used radioactive phosphorous (virus has radioactive DNA) when injected into bacteria it was radioactive. They learned DNA holds the instructions and is the genetic material. |
What contribution did Erwin Chargaff provide for the structure of DNA? | Discovered they key facts needed to determine the structure of DNA [Base Pair Rules(A-T, G-C)] |
How did Rosalind Franklin and Maurice Wilkins' contribute to the knowledge of DNA? | Took X-Ray photos of DNA. |
What contribution did James Watson and Francis Crick provide for the structure of DNA? | Built 3D model of DNA. |
Describe what double helix means. | Twisted Double Strand |
What does DNA stand for? | Deoxyribonucleic Acid |
Where is DNA located? | In the Nucleus |
What are the three main parts of a DNA nucleotide? | Phosphate group, 5 Carbon Sugar, Nitrogen Base |
What is the "Backbone" of the double helix made of? | Sugar and Phosphate |
Where in the double helix are the nitrogen bases located? | In the rungs of the ladder |
What are the four nitrogen bases in DNA? | Adenine, Cytosine, Thymine, Guanine |
What are the base pair rules? | A-T, G-C |
Why do the nitrogen bases pair up the way they do? | For the same width all the way down and to maximize the number of hydrogen bonds. |
Which two are Pyrimidines? | C & T |
Which two are Purines? | A & G |
How are the Pyrimidines and the Purines different? | Pyrimidines are a single ring of carbon and nitrogen. Purines are double rings. |
Which carbon is the phosphate group attached to? | 5th carbon |
Which carbon is the nitrogen base attached to? | 1st carbon |
What is DNA replication? | The process of making exact copy of DNA. |
What does helicase do? | Breaks up the hydrogen bonds that link the bases. |
What does DNA polymerase do? | Adds nucleotides to exposed bases, proofreads DNA |
What does ligase do? | Bonds Okazaki fragments together |
What does primase do? | Builds an RNA primer |
How many DNA polymerase enzymes can replicate a strand of DNA at one time? | Thousands |
In prokaryotes, how many points of replication are there? | 2 |
What does semi-conservative mean with regards to DNA replication? | Half the original DNA strand is used in the new strand. |
What is a primer? Why is it needed? | Primer allows DNA polymerase (attaches to RNA to start its job) to begin replication. |
In what direction does DNA polymerase add nucleotides? | 5 to 3 |
What does anti-parallel mean? | One strand is going 5 to 3. The other is 3 to 5 |
What is the location called where the two DNA strands are being separated? | Replication Fork |
What is a leading strand? | Built continuously |
What is a lagging strand? | Built in fragments |
What are the fragments called that make up the lagging strand? | Okazaki fragements |
Explain the entire process of how a strand of DNA is replicated. | Helicase splits the DNA (breaks the H bonds) DNA polymerase (p) does job on the leading & lagging strand. Primase builds RNA primer (P) the DNA p attaches to primer & builds chunks of DNA. The ligase connects the chunks & gets rid of P besides P on end. |
In our DNA extraction lab, why did you have to add detergent? | It breaks down lipids & membranes. |
In our DNA extraction lab, why did you have to add meat tenderizer? | It breaks down proteins that make the DNA coil. |
What was the ingredient in the meat tenderizer we were really using? | Enzymes |
In our DNA extraction lab, why did you have to add alcohol? | In order for the proteins and lipids to not reattach to the DNA, to extract DNA. |
Why wouldn't the lab worked if we added the meat tenderizer before the detergent? | The meat tenderizer could not get to the proteins if the membrane was still there. |
What does DNA code for? | Proteins |
What is a gene? | Section of DNA that codes for a protein. |
What does RNA stand for? | Ribonucleic Acid |
What are the three differences between DNA and RNA? | DNA is double stranded, uses Deoxyribose, and "Thymine". RNA is single stranded, used Ribose, and "Uracil" |
Which carbon loses the oxygen to turn RNA into DNA? | 2nd Carbon |
What are the three types of RNA? | mRNA, tRNA, rRNA |
What is transcription? | Writes DNA's message into mRNA |
What is the role of messenger RNA (mRNA)? | Rewrites message as codons, carries message from nucleus to ribosomes. |
Where does transcription take place? | Nucleus of a cell. |
What enzyme is responsible for transcription? | RNA polymerase |
What is the role of rRNA? | Builds ribosomes |
What is an intron? | Parts of DNA that doesn't hold information. |
What is and exon? | Parts of DNA that hold genetic information. |
What is translation? | Translates mRNAs message to anticodons to bring correct amino acid. mRNA to Proteins. |
Where does translation take place? | Cytoplasm/Ribosomes |
What do we call the three letter sequences in DNA and mRNA that get "read"? | Codons |
What do codons code for? | Amino Acids |
What is the start codon and which amino acid does it code for? | AUG, codes for met |
What is a stop codon? | UGA, UAA, UAG |
What is the purpose of translation? | To translate DNA to RNA so it can travel outside of Nuclear membrane, to give info. to ribosomes, to build proteins. |
What is the role of transfer RNA? | brings in amino acids and puts them in order. |
What is an anti-codon? | 3 letters in tRNA |
What amino acid do all proteins begin with? | MET |
What type of bonds are formed between the amino acids? | Peptide bonds |
How many nucleotides are in one codon? | 3 |
What indicates to the ribosome complex that translation is finished? | The stop codon |
Is there an amino acid added at a stop codon? | NO |
Explain the entire process of how we go from the DNA code to a functional protein. | DNa is turned to mRNA in nucleus. mRNA travels to cytoplasm/ribosome (R). R read mRNA, translation occurs after the start codon, goes until stop codon & protein is released. R pull in RNA & puts the AA's in correct order, tRNA goes & picks up another AA. |
What is a mutation? | A change in DNA. |
What is a mutagen? | Anything that causes a mutation. |
What are some causes of mutations? | Radiation, Smoking, Diet. |
What does it mean if we say a cell is a mutant cell? | Contains a mutation. |
If a mutation occurs in a somatic cell, will that mutation be passed on the daughter cell after mitosis? | Yes |
If a mutation occurs in a somatic cell, will that mutation be passed on to your offspring? | No |
If a mutation occurs in a gamete, will that mutation be passed on to your offspring? | Yes |
What are the two main types of mutations? | Point Mutations & Chromosomal Mutations |
What is a point mutation? | A small mutation that occurs at one point. |
What is a substitution mutation? | Swapping one base for another |
What is a deletion mutation? | Remove a base, frameshift, dangerous, rare |
What is an insertion mutation? | Adding a base, frameshift, dangerous, rare |
What mutations cause a frameshift? What is a frameshift? | Deletion & Insertion, It is where all the bases are shifted over to make new codons/proteins. |
What is a silent mutation? | When a mutation goes unnoticed, protein does not change. |
What is a missense mutation? | When a protein changes from one amino acid to another. |
What is a nonsense mutation? | When the changed codon changes to a stop codon. |
What are the four types of chromosomal mutations? | Deletion, Duplication, Inversion, Translocation |