Answer:
D. Polymerase chain reaction
Explanation:
PCR is very percise; used to amplify or copy a specific DNA target from a mixture of DNA molecules by:
- two short DNA sequences (primers) are bind to start and end the DNA target
- perform the PCR; DNA templates is added to a tube that contains primers, free nucleotides, and the enzyme (DNA polymearse)
- it is mixed in a PCR machine that increases and decreases the temperature of the sample
- mixture is heated to seperate the double strnaded DNA templated into single strands
- mixture is cooled so the primers can bind to the DNA template
- the DNA polymerase will synthesize to new strands of DNA from the primers
- during synthesis, the end of the first cycle, the DNA molecule will consist of a new and old DNA strand
- PCR continues with added cycles to repeat the steps
- newly synthesized DNA segements serve as templates in later cycles; which can be copied over and over.
The sun is Gaseous, and has three layers
I think it is D because your responding to the cold from stimuli and by creating heat to keep your body the average temperature it is homeostasis.
1859
On the Origin of Species (or more completely, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life), published on 24 November 1859, is a work of scientific literature by Charles Darwin which is considered to be the foundation of evolutionary biology.