Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

[Q]: Context: DNA and RNA are nucleic acids. DNA stores genetic information. RNA helps build proteins. Proteins, in turn, determine the structure and function of all your cells. Proteins consist of chains of amino acids. A proteins structure and function depends on the sequence of its amino acids. Instructions for this sequence are encoded in DNA. In eukaryotic cells, chromosomes are contained within the nucleus. But proteins are made in the cytoplasm at structures called ribosomes. How do the instructions in DNA reach the ribosomes in the cytoplasm? RNA is needed for this task. RNA stands for ribonucleic acid. RNA is smaller than DNA. It can squeeze through pores in the membrane that encloses the nucleus. It copies instructions in DNA and carries them to a ribosome in the cytoplasm. Then it helps build the protein. RNA is not only smaller than DNA. It differs from DNA in other ways as well. It consists of one nucleotide chain rather than two chains as in DNA. It also contains the nitrogen base uracil (U) instead of thymine (T). In addition, it contains the sugar ribose instead of deoxyribose. You can see these differences in Figure 5.16. There are three different types of RNA. All three types are needed to make proteins. Messenger RNA (mRNA) copies genetic instructions from DNA in the nucleus. Then it carries the instructions to a ribosome in the cytoplasm. Ribosomal RNA (rRNA) helps form a ribosome. This is where the protein is made. Transfer RNA (tRNA) brings amino acids to the ribosome. The amino acids are then joined together to make the protein. How is the information for making proteins encoded in DNA? The answer is the genetic code. The genetic code is based on the sequence of nitrogen bases in DNA. The four bases make up the letters of the code. Groups of three bases each make up code words. These three-letter code words are called codons. Each codon stands for one amino acid or else for a start or stop signal. There are 20 amino acids that make up proteins. With three bases per codon, there are 64 possible codons. This is more than enough to code for the 20 amino acids plus start and stop signals. You can see how to translate the genetic code in Figure 5.17. Start at the center of the chart for the first base of each three-base codon. Then work your way out from the center for the second and third bases. Find the codon AUG in Figure 5.17. It codes for the amino acid methionine. It also codes for the start signal. After an AUG start codon, the next three letters are read as the second codon. The next three letters after that are read as the third codon, and so on. You can see how this works in Figure 5.18. The figure shows the bases in a molecule The genetic code has three other important characteristics. The genetic code is the same in all living things. This shows that all organisms are related by descent from a common ancestor. Each codon codes for just one amino acid (or start or stop). This is necessary so the correct amino acid is always selected. Most amino acids are encoded by more than one codon. This is helpful. It reduces the risk of the wrong amino acid being selected if there is a mistake in the code. The process in which proteins are made is called protein synthesis. It occurs in two main steps. The steps are transcription and translation. Watch this video for a good introduction to both steps of protein synthesis: [Link] MEDIA Click image to the left or use the URL below. URL: Transcription is the first step in protein synthesis. It takes place in the nucleus. During transcription, a strand of DNA is copied to make a strand of mRNA. How does this happen? It occurs by the following steps, as shown in Figure 5.19. 1. An enzyme binds to the DNA. It signals the DNA to unwind. 2. After the DNA unwinds, the enzyme can read the bases in one of the DNA strands. 3. Using this strand of DNA as 
 Question: _____double-stranded nucleic acid
[A]: dna


[Q]: Context: Officials in the Midwestern U. S. town of Joplin, Missouri, say the death from Sundays' big tornado reaches 116 and that search efforts continue for possible survivors trapped in rubble . Search and rescue teams are conducting their third sweep through the nearly 10 kilometer - long and one - kilometer wide area of destruction left by the tornado. They are working as quickly as possible while weather conditions remain relatively stable. More storms are forecast for the area. Joplin Fire Chief Mitch Randles said there are areas with large piles of rubble that might hold survivors. "We are still finding individuals. We did rescue seven individuals from underneath rubble yesterday and, of course, we are also finding dead folks as well." Said more folks and that is why we are doing these searches. We want to make every opportunity that we can to find everybody that is in the rubble and that has survived to this point." Randles said the current sweep involves a slower pace that previous searches and that he plans a fourth search, possibly on Wednesday, using specially trained dogs. "We are searching every structure that has been damaged or destroyed in a more in-depth manner, "he said." I have dogs and dog handlers coming from all over the country do help us in that effort." Joplin City Manager Mark Rohr said the Red Cross and other volunteer organizations are helping people who were left homeless by the tornado and that the Federal Emergency Management Agency, or FEMA, is on hand to help. "Joplin is a great city. We have suffered a great loss, "said Rohr." We will recover and we will recover strongly and we have a lot of help and a lot of volunteers to make that easier." The tornado that struck Joplin was classified by the Natioonal Weather Service as an F - 4, with winds of more than 300 kilometers per hour. It lasted only 20 minutes, but it killed more that 100 people, injured more than 400 others, and destroyed or heavily damaged some 2,000 homes, businesses, churches and a hospital. Authorities have registered more than 1,700 calls about missing people and they hope to _ most of those cases soon, as victims are identified and survivors come forth and reunite with loved ones. This was the worst tornado to strike the United States in 60 years. It was the latest in a wave of violent storms that have swept Midwestern and southern states in recent weeks, leaving more than 300 people dead an causing more than $2 billion dollars in damage. 
 Question: What kind of disaster of this article is talking about?
[A]: tornado


[Q]: Context: Circular RNAs (circRNAs) are a class of newly-identified non-coding RNA molecules. CircRNAs are conserved across different species and display specific organization, sequence, and expression in disease. Moreover, circRNAs' closed ring structure, insensitivity to RNase, and stability are advantages over linear RNAs in terms of development and application as a new kind of clinical marker. In addition, according to recent studies, circular RNA-7 (ciRS-7) acts as a sponge of miR-7 and thus inhibits its activity. Numerous evidences have confirmed expression of miR-7 is dysregulated in cancer tissues, however, whether ciRS-7 invovled in oncogenesis by acting as sponge of miR-7 remains unclear. Most recently, a study reported ciRS-7 acted as an oncogene in hepatocellular carcinoma through targeting miR-7 expression. This suggest ciRS-7/ miR-7 axis affects oncogenesis, and it provides a new perspective on the mechanisms of decreased miR-7 expression in cancer tissues. Discovery of sponge role of circRNAs caused researchers to more closely explore the underlying mechanism of carcinogenesis and has significant clinical implications, and may open a new chapter in research on the pathology and treatment of cancers. This review summarizes the structure and function of circRNAs and provides evidence for the impact of ciRS-7 in promoting the development of cancer by acting as sponge of miR-7. 
 Question: Which miRNA is associated with the circular RNA ciRS-7?
[A]:
mir-7