Uracil (U) is not part of DNA but is part of RNA
Answer:
Despite the hours of sunlight a city receives, the latitude of the city plays a larger role due to the fact that with a higher latitude, the higher the solar angle allowing a city to be much warmer.
Explanation:
I would say the microscope....................
Answer:
A Ligase
B False
C To separate the double‑stranded DNA
Explanation:
The Polymerase Chain Reaction (PCR) is a technique widely used in molecular biology laboratories in order to make millions of copies of a specific sequence of DNA. PCR requires deoxynucleotide triphosphates (dNTPs) to synthesize new copies of the target DNA fragment, a thermostable DNA polymerase that adds nucleotides to new DNA strands, and primers that attach to complementary ends at each DNA strand. PCR has three phases: 1-Denaturation, where the double-stranded DNA molecule is heated to separate it into two single (separated) strands; 2-annealing, where the temperature is lowered in order to allow the primers to attach each DNA strand, and 3- extension, where the temperature is increased (again), and the thermostable DNA polymerase adds the appropriate dNTPs to new DNA strands. In consequence, annealing occurs at the lowest temperature. Moreover, during the denaturation stage, the temperature is increased at 90–95°C in order to denature the DNA strands into single strands.
Answer: A
Explanation:The Trp operon is responsible for synthesis of the amino acid trytophan when it is not available in the cellular environment.
When the tryptophan is plentiful, a repressor protein binds to two molecules of tryptophan.
Thiss repressor-tryptophan complex binds to the trp operator. This binding prevents the binding of RNA polymerase, so the operon is not transcribed, and no new trptophan is produce.
On the other hand, when tryptophan levels are reduced, the inactive repressor will not bind the tryptophan operator so the operon is transcribed.
Regulation of the trp operon is determined by the concentration of tryptophan; when adequate tryptophan is present in the growth medium, there is no need for tryptophan biosynthesis.
Transcription is turned off when a high concentration of tryptophan is present, and is turned on when tryptophan is absent. The regulatory signal is the concentration of tryptophan itself.
Therefore in the absence of tryptophan, the inactive repressor cannot bind trpO, so operon gene transcription occurs.