Molecular Biology of Genes
How many different types of DNA nucleotides are they?
4
Which is the following are characteristics of the genetic material that early scientists were seeking?
Able to undergo mutations, Storage of genetic information, A stable molecule.
When two molecular strands are connected but oriented in opposite directions, the strands are said to be?
Antiparallel
Who first demonstrated that DNA was a genetic material?
Avery, MacLeod, and McCarthy
What is the best explanation as to why the number of adenines in an organism's DNA is equal to its number of thymines?
Because adenine pairs with thymine in DNA
Which of the following are similarities between prokaryotic and eukaryotic DNA replication?
Both involve DNA polymerase Both happen from 5' to 3' direction Both result in 2 copies from one parent molecule Both are semi conservative
An opening in eukaryotic DNA, containing two forks at the site of replication is called a replication—?
Bubble
In prokaryotes, replication can occur in two directions at once because the DNA molecule is?
Circular
Around 1950, the hypothesis that proteins were the genetic material was backed up by what evidence?
Contains 20 different amino acids for variety of information. Associated with chromosomes.
Transcription
DNA is used as a template to produce RNA.
Replication
DNA is used as a template to produce duplicate molecules of DNA.
Rosalind Franklin was instrumental in the discovery that the three-dimensional shape of a DNA molecule was a(n)?
Double helix
The two strands of DNA are held together by—?
Hydrogen bonds
It is necessary for genetic material to be able to undergo changes called—, in order to provide genetic variety for evolution to occur.
Mutations
DNA is composed of units called—, each of which contains a phosphate group, a 5-carbon sugar,and one of 4-nitrogen-containing based.
Nucleotides
Which of the following are components of a nucleotide?
Phosphate, 5-carbon sugar and Nitrogen-containing base.
The enzyme that is used to proofread DNA as it is being synthesized is DNA—?
Polymerase
In the 1940s, scientists had concluded that the genetic material was most likely either?
Proteins or DNA
Translation
RNA is used to produce protein.
What is the function of DNA polymerase?
Remove RNA primers Proofreads newly formed DNA Synthesizes DNA in the lagging strand Synthesizes DNA in the leading strand
The process of copying a DNA molecule so that there are two copies of the same DNA is called DNA—?
Replication
Who contributed to the determination of the shape of the DNA molecule through X-ray crystallography?
Rosalind Franklin
Why must the genetic material be a stable molecule?
So genetic material can pass from generation to generation and So replication can be accurate
The parental strand of DNA serving as the guide for a complementary DNA daughter strand is called the —— stand.
Template
The sequential steps of DNA replication in prokaryotes.
The double helix is separated and unwound DNA polymerase begins the copying process DNA polymerases meet at the termination region
In Griffith's experiment, R strain bacteria acquired a substance from the S strain bacteria. The R strain bacteria was changed or—?
Transformed.
True/False: DNA can store information, can be replicated and can undergo rare changes.
True.
True/False: A purine base normally pairs with a pyrimidine base.
True. A(purine) pairs with T(pyrimidine) and G(purine) pairs with C(pyrimidine).
Steps of DNA replication
Unwinding the DNA double helix Complementary base pairing Joining nucleotides to the growing DNA strand
Summary of Chargaff's rules about DNA.
Within a species, the number of guanine equals the number of cytosine, and the number of thymine equals the number of adenine. Also the amount of A, T, G, and C in DNA varies between species.
James Watson and Francis Crick contributed greatly to our knowledge of the structure of the molecule known as?
DNA