General Ecology Finals Part 2 Flashcards
When was DNA first noticed and who noticed it?
in 1869; Friedrich Miescher
How was DNA first discovered and what was it called?
Friedrich Miescher isolated it from nuclei of white blood cells; He called it “nuclein”
In 1895, Edmund Wilson first suggested that DNA might be [..]. He observed that [..] and [..] contribute the same number of [….] during reproduction.
hereditary material; sperm and eggs; chromosomes
DNA is a polynucleotide consisting of what four repeating subunits and held together by what bonds?
adenine (A), thymine (T), cytosine (C), and guanine (G), held together by covalent bonds
In 1923, DNA was localized to […] and made a candidate for the […]. However both […] and […] are found in […].
chromosomes; the hereditary material; proteins and RNA; chromosomes
What other candidates are there for the hereditary material besides DNA?
Lipids and carbohydrates
Frederick Griffith identified two strains of Pneumococcus: S, which caused […] in mice, and R which […]. A single gene mutation change can convert an […] strain to an […] strain of the same antigenic type.
fatal pneumonia; did not;
S (smooth); R (rough)
Griffith proposed the transformation factor as the molecule that transformed the […] into […]. He said the transforming factor carried […] but he could not identify the […]
R I I ; S I I I; hereditary information; molecule
Avery, MacLeod, and McCarty used […] and [..] to infect mice. The […] of heat-killed S I I I bacteria was divided into […] and treated to destroy either [..], [..], [..], or [..] and [..] before mixing with live RII bacteria.
heat-killed S I I I bacteria; live R I I bacteria; extract; aliquots; DNA, RNA, proteins, or lipids and polysaccharides
[..] in 1952, showed that D N A is responsible for bacteriophage infection of bacteria cells. What are bacteriophages? Phages such as T2 have a […] that attaches to the host cell and a head that contains [..]
Hershey and Chase; viruses that infect bacteria; protein shell with a tail segment; D N A
Phages must infect [..] to reproduce. How does infection begin?
bacterial hosts; when the phage injects DNA into the bacterial cell and leaves its protein shell on the surface;
The phage DNA replicates in the bacterium and produces [..] that are assembled into […]—these are released by [..]
proteins; progeny phage; the host cell
DNA structure identified by […] and modeled by [..] and [..].
Rosalind Franklin;Watson; Crick
DNA composed of four kinds of [..], A, T, C, and G, joined by […] with [..] that come together to form a [..]
nucleotides; covalent phosphodiester bonds; two polynucleotide chains; double helix
What is a DNA nucleotide composed of?
sugar, one of four nitrogenous bases, and up to three phosphate groups
What is deoxyribose? How many carbons does it have and what are they identified as?
the sugar of DNA nucleotides; it has five carbons, identified as 1′, 2′, 3′, 4′, and 5′
A nucleotide base is attached to what? A hydroxyl group is attached to what? 1-3 phosphates are attached to what?
1′ carbon; 3′ carbon; 5′ carbon
How many rings do pyrimidines and purines have. Which nucleotides are pyrimidines and which are purines?
pyrimidines (thymine and cytosine) - single ring. purines (adenine and guanine) - double ring
Deoxynucleotide monophosphates that are part of a polynucleotide chain have [..] and are called [..] where N refers to what? Deoxynucleotide triphosphates (d N T P s) are not part of a [..].
single phosphates; dNMPs; four bases; polynucleotide chain
Individual nucleotides are assembled into [..] by the enzyme [..]. It catalyzes the formation of a [..] between the […] and the […] of an adjacent one
chains; DNA polymerase; phosphodiester bond; 3′ hydroxyl group of one nucleotide; 5′ phosphate
Each polynucleotide chain has a [..] , consisting of [..] and [..]
sugar-phosphate backbone; alternating sugar; phosphate groups
