instruction:
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.
question:
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
answer:
dna

question:
Context: Modeled after US hot website.com, group buying websites are now popular in China. These websites use the power of group buying to get competitive discounts for a daily deal on some best stuff to do, see, eat and buy in the cities across China. Discounts are available within just one click. Zhao lei, a software engineer in Beijing, loves the one-hour lunch break at noon,as it is the best time for him to check "today's special" at his favorite group buying websites . Sometimes he searches for great deals at directory sites devoted to the new shopping space. Zhao spends around 800 yuan($117.65) on group buying every month, mostly to buy food coupons for eating at some nice restaurants and occasionally to find something fun to do. " I love group buying. In addition to the competitive discounts it offers, it helps me get something fun, exciting and new, and such surprises give me a reason to try something new," he said. When he finds a really good bargain, he will send the link to friends or colleagues through MSN,QQ, or e-mail, or share the information at some social networking websites. In doing so, he often gets a certain cut off the price. At some sites, buyers are invited to leave notes about what they want to buy and the website will consider it if similar applications reach a certain number. That is how Zuo got her digital camera after waiting for two months. "It is cool. I want to buy a new digitgal camera for my trip to Switzerland this winter, but I never expected such cheap prices!" Zuo said.
Question: What is the passage mainly about?
answer:
group buying

question:
Context: Nerve growth factor (NGF) is an important mediator of pain and hyperalgesia and has become a target of novel analgesic therapeutics. Tanezumab is a humanized IgG(2) antibody that binds NGF with high affinity and specificity. In a study to assess the toxicity and pharmacokinetic properties of tanezumab in adult, male and female, cynomolgus monkeys following weekly intravenous administration of 1, 10, or 30 mg/kg for up to 26 weeks (followed by an 8-week recovery period), tanezumab was well tolerated with no macroscopic or microscopic effects on those brain, spinal cord, nerve, or ganglia sections evaluated. One fifth of tanezumab-treated monkeys developed an antibody response to tanezumab that prevented maintenance of tanezumab exposure between dosing. In the antibody-negative animals, accumulation of tanezumab was observed; steady state was achieved approximately 8 weeks after the first dose of study drug, and exposure to tanezumab was approximately dose proportional with no observed difference between male and female animals. One monkey died during the study; this monkey had findings suggestive of hypersensitivity reaction. The favorable toxicity and pharmacokinetic profile of tanezumab seen in this study supports its further evaluation for the treatment of pain in clinical practice.
Question: What is the target of tanezumab?
answer:
ngf