Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
|
What experiment did Griffith do and how did it help in the discovery of DNA? |
He performed a experiment with mice and different viruses. He discovered the transformation factor and raised the question about how can DNA from a dead organism be replicated in a live organism. |
|
|
What did Hershey and Chase do? |
In 1952, they did an experiment with radioactive phosphorus and sulfur and viruses. When replication occurred, looked at where the radioactive isotope was. When it was in the cell and not the protein capsid(sulfur) they realized replication info occurred in DNA(phosphorus, CHONP). |
|
|
Who was the first to ignite the experimentation on DNA and what did they discover? |
Meischer discovered that the nuclei had larger pieces that weren't proteins. |
|
|
What did Hammerling discover and how? |
he worked with single-celled algae and discovered that information for replication was in the nucleus. |
|
|
What happened in 1953? |
Watson and Crick were credited to the discovery of DNA structure. However, Rosalind Franklin helped them by providing x-rays of helical DNA structure. |
|
|
What are the pyrimidines and purines? What is the difference. |
pyrimidines: one carbon ring, smaller, thiamine and cytosine purines: 2 carbon rings, adenine, guanine, bigger |
|
|
Why can't T-G or C-A bond? |
They would be unstable due to the lack of H-bonds. |
|
|
How does a strand get a 5' or 3'? |
Depending what carbon the phosphorus is bonded to in the sugar-phosphate back bone. |
|
|
How are the nucleotides connected? |
They are connected by hydrogen bonds. 3 between C-G and 2 between A-T. The nucleotides are also antiparallel. |
|
|
What is a codon? |
3 nucleotides. |
|
|
What is a nucleosome? |
One bundle of nucleotides coiled around a set of histones. |
|
|
What are histones and what is their purpose? |
8 positively charged proteins. First step in coiling DNA so it can be better organized and compacted. |
|
|
What does DNA stand for? |
Deoxyribose(5-c carbon), nucleic, acid(negatively charged). |
|
|
What is the first enzyme in DNA replication? What does it do? |
Helicase breaks h-bonds. |
|
|
What keep the nucleotides from annealing? |
Single-stranded proteins |
|
|
What does DNA polymerase 3 do? |
Builds complementary strands but can only work from 5' to 3'. |
|
|
What assists DNA polymerase 3? |
RNA primase initiates the strand by putting a temporary set of nucleotides. In the lagging strand there are multiple which create Okazaki fragments. |
|
|
What happens once the DNA polymerase 3 has finished the sequence? |
DNA polymerase 1replaces the RNA primers. DNA ligase then joins the Okazaki fragments with phosphodiester bonds in the lagging strand. |
|
|
What are the 2 main steps in protein synthesis? |
Transcription(mRNA) and translation (tRNA). |
|
|
Why does protein synthesis occur? |
DNA is too valuable to leave the nucleus. It must be decoded/ put into another language so parts of the cell can create the protein that will then express the gene. |
|
|
What is a codon? What is an anticodon? |
Codon is a set of 3 nucleotides that code for an amino acid. Anticodon is the opposite 3 nucleotides of the codon. ex. AUG - UAC |
|
|
What are the levels of protein synthesis regulation? |
transcriptional, post-transcriptional, translational, post-translational |
|
|
What is the difference between Tracnscriptional and Tanslational? |
Transcrip.: what genes get transcribed(what part of DNA) Transl: how fast does mRNA get translated into protein Transcrip is before mRNA is created. |
|
|
Whats the dif between Transcriptional and post-transcriptional? |
Transcrip.: what genes get transcribed(what part of DNA) Post: do introns/exons need to be removed Section has already been chosen but are there useless parts. |
|
|
What is Post-translational regulation? |
Does it need to be modified before translated to protein? |
|
|
What are introns and axons? |
Introns are useless segments on a DNA strand. They must be chopped out and the axons spliced together before mRNA is translated. |
|
|
What is the difference between a missense and a nonsense mutation? |
Missense: sub/rearrange, affects one codon Nonsense: switch a codon for stop codon Non-sense is a type of missense |
|
|
What does a frameshift mutation affect? |
Affects ALL of the sequence, add or sub |
