What role does the pcr play in the analysis of edna? a. it generates larger amounts of dna from tiny amounts. b. it sorts different sizes of dna fragments into a banding pattern. c. it breaks dna into fragments that vary in size. d. it purifies any dna obtained from the environment.

The right answer is A.  it generates large amounts...

PCR is the acronym for Polymerase Chain Reaction, this Molecular Biology method was developed in 1985 by Kary Mullis, who obtained the Nobel Prize in Chemistry for this work in 1993. This revolutionary process coupled with the use of a heat-resistant DNA polymerase makes it possible to obtain, without cloning. , a considerable amplification of a given fragment of DNA.

The PCR reaction makes it possible to amplify in vitro a specific region of a given nucleic acid in order to obtain an amount sufficient to detect and study it.

To do this, a series of reactions allowing the replication of a double-stranded DNA template is repeated in a loop. Thus, during the PCR reaction, the products obtained at the end of each cycle serve as a template for the next cycle, the amplification is therefore exponential.

To have double-stranded DNA replication, you have to act in three steps.

* DNA must be denatured to obtain single-stranded matrices: denaturation.

* Borne and initiate replication of the sequence to be amplified using oligonucleotide specific primers: hybridization.

* Perform the polymerization reaction of the complementary strand. At the end of each cycle, the products are in the form of double-stranded DNA: polymerization.

The three steps, constituting a PCR cycle, are carried out at different temperatures to control the enzymatic activity.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms