Testosterone<span> begins the development of secondary sexual characteristics.</span>
<span>The correct option is: IT HELPS CARRY AN IMPULSE BACK TO THE NEXT NEURON. There are two types of neurons, excitatory and inhibitoty neurons. Both serve to transmit impulse from one point to the other. Each neuron usually makes several connections with other cells.</span><span />
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'.