Answer:
B. Use the polymerase chain reaction (PCR) to make multiple copies of the DNA.
Explanation:
The scientist is to analyze a small sample of DNA, the most useful step to start this would be first the use of polymerase chain reaction to make various copies of that DNA sample. PCR is essential and quick process that gives a lot of copies within few hours. It uses the sample or target DNA, according to which the primers are designed. Taq polymerase and DNA polymerase are also used in the process, it consist of various cycles in which copies are made. There are three basic steps 'Denaturation', 'annealing', and 'extension'.
<h2>Given statement is false</h2>
Explanation:
According to dispersive model of DNA replication,DNA molecules are hybrids of parental and daughter DNA;In this model each individual strand is a combination of original and new DNA
Meselson and Stahl did an experiment on DNA replication using E.coli bacteria
- E.coli was grown in a medium containing heavy isotope of nitrogen,bacteria took up the nitrogen and used to synthesize new biological molecules,including DNA
- It was grown for many generations,the nitrogenous bases of the bacteria's DNA were all labelled with heavy nitrogen
- Bacteria were then switched to light nitrogen isotope and allowed to grow for several generations
- They then measured the density of the DNA using density gradient centrifugation
- This method separates molecules such as DNA into bands by spinning them at high speeds in the presence of another molecule, such as cesium chloride
- Each DNA produced two DNA molecules each with one new strand and one old strand called semi conservative replication(half of the parental DNA conserved in daughter DNA)
- Each DNA strand act as a template for synthesis of new strand
- Hence,dispersive model of DNA was eliminated and semi-conservative model of DNA replication was proved by the above experiment
I’m not sure. Im pretty sure it’s D.
Answer:
12!
Explanation:
Sex cells only carry half of what makes up the organism's DNA. This is so that when they find a mate, in this case- another tomato, their sex cells and their partner's sex cells will add up to the appropriate amount of chromosomes in the organism's DNA. In this case, 24.
They're found orbiting around outside the nucleus, because they're electrons
I hoped this helped! :)