During normal breathing, the brain is stimulated to breath with increasing acidity as a result of CO2 concentration from basic metabolic processes. The brain is quite selfish and only really wants to maintain it's pH which should be at a range of 7.3-7.45, and will not tolerate any decrease.
In patients who have a chronic respiratory disorder with things like COPD. The brain has become accustomed to excessive acidic content, and is now stimulated by the Hypoxic drive or by low oxygen content.
Have a control. You have to have something to compare your experimental results or else your results could be random chance.
The pentose sugar on RNA is called ribose. (a trick to remember it is that the "R" in RNA stands for ribo)
Hope this helps :)
The correct answer is: c. An operon is a region of DNA that codes for a series of functionally related genes under the control of the same promoter.
Operons contain cluster of genes that are transcribed together into mRNA or are not expressed at all. Formed mRNA undergos splicing to create monocistronic mRNAs so that can be translated separately. Operons are more often found in prokaryotic cells but it can appear in eukaryotic cells and in viruses.