Lecture 10: DNA Structure / Function and Protein Production Flashcards
DNA and RNA are both sources of genetic information. They are made from ___.
Nucleic Acids
Nucleotides with two carbon rings include Adenine and Guanine. These are called ___.
Purines
Nucleotides with one carbon ring include Thymine and Cytosine. They are called ___.
Pyrimidines
Nucleotides have three main parts to them. They are ___, ___ and ___.
Ribose sugar, phosphate, and nitrogenous base
What major contributions did Rosalind Franklin (1958) make?
Used X-rays of DNA to help determine its shape
What major contributions did Erwin Chargaff (1952) make?
Discovered A=T and C=G
What major contributions did Frederick Griffith (1928) make?
Discovered that information could be exchanged between cells
What major contributions did Hershey and Chase (1952) make?
Discovered that genetic information was stored in DNA by using radioactive isotopes
What major contributions did Watson and Crick (1953) make?
Wrote the paper which completely described the DNA molecule
What carbon does the phosphate group attach to on the sugar of a nucleotide?
5th carbon
Which carbon does the nitrogenous base attach to on the sugar of a nucleotide?
1st carbon
During DNA replication, new DNA nucleotides are put into place by the ___ enzyme.
DNA Polymerase
During DNA replication, the existing DNA molecule is “split” by the ___ enzyme, allowing new nucleotides to be put into place.
Helicase
Basically speaking, DNA replication is important because ___.
The existing DNA molecule is the template for an exact copy to be made so the cell can divide.
What “direction” does DNA replication take place?
5’ to 3’
Why does adenine always bond with a thymine?
They share two hydrogen bonds
Which two nucleotides are “purines”?
Adenine and Guanine
What in the cell builds the protein?
Ribosome
What conveys information and instructions to ribosomes?
mRNA
What contains anti-codons?
tRNA
What contains codons?
mRNA
Which form of genetic information includes thymine?
DNA
Which form of genetic information includes uracil?
mRNA
Which form of genetic information provides amino acids to the ribosome?
tRNA
Which form of genetic information is produced in the nucleus and travels to the cytoplasm?
mRNA
What does Transcription convert?
DNA into mRNA
What does translation convert?
mRNA into proteins
Where does transcription take place?
The nucleus
Where does translation take place?
In the cytoplasm
Where does the DNA molecule open up when a protein is needed?
Only at the gene needed
When the RNA polymerase makes RNA, and “editing” process occurs. What happens during this “eukaryotic processing” in order to make mRNA?
Introns are removed and exons are spliced together
DNA to ___ to mRNA
During eukaryotic processing, what molecule is first made?
hnRNA
How many letters of RNA make up a single codon?
3
The term “gene expression” means that proteins are produced by the DNA. This is also called the “phenotype.” True or false.
True
The enzyme ____ makes new DNA, and if it makes a mistake, can cause a mutation.
DNA Polymerase
What is a missense mutation?
When a mutation results in a similar protein, with little effect, or major impact to the protein
What is a nonsense mutation?
When a stop code on is inserted in the middle of a protein, severely altering it
What is a silent mutation?
When a mutation results in the same protein, with no true impact
What is an insertion mutation?
A frameshift mutation that shifts nucleotides to the right. Often fatal to the cell
What is a deletion mutation?
A frameshift mutation that shifts nucleotides to the left. Often fatal to the cell
What is a substitution mutation?
A substitution of one nucleotide for another. Effects range from no change to the protein, minor changes to the protein, or major changes
