Ques:Answer the following question given this paragraph: The target cell then needs to be able to recognize the signal. Chemical signals are received by the target cell on receptor proteins. Most receptor proteins are found associated with the plasma membrane, but some are also found inside the cell. Receptor proteins are very specific for only one particular signal molecule, much like a lock that recognizes only one key. Therefore, a cell has lots of receptor proteins to recognize the large number of cell signal molecules. There are three stages to sending and receiving a cell "message:" reception, transduction, and response. Q: Chemical signals are received by the target cell on what? Choices: - acidic proteins - inceptor proteins - parent proteins - receptor proteins A:

Ans:receptor proteins
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Ques:Answer the following question given this paragraph: Within seconds of birth, the umbilical cord is cut. Without this connection to the placenta, the baby can't exchange gases, so carbon dioxide quickly builds up in the baby's blood. This stimulates the baby's brain to trigger breathing, and the newborn takes her first breath. Q: What structure connects the fetus to the placenta, allowing the exchange of gases? Choices: - sediment cord - skin cord - belly button - umbilical cord A:

Ans:umbilical cord
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Ques:Answer the following question given this paragraph: For natural selection to take place, organisms must vary in their traits. Asexual reproduction results in offspring that are all the same. They are also identical to the parent cell. So how can prokaryotes increase genetic variation? They can exchange plasmids. This is called genetic transfer . It may happen by direct contact between cells. Or a "bridge" may form between cells. Genetic transfer mixes the genes of different cells. It creates new combinations of alleles. Q: What is the exchange of plasmids by prokaryotes called? Choices: - biochemical transfer - artificial transfer - transcription - genetic transfer A:

Ans:genetic transfer
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Ques:Answer the following question given this paragraph: Assume you are finding the area of a rectangle with a length of 6.8 m and a width of 6.9 m. When you multiply the length by the width on your calculator, the answer you get is 46.92 m 2 . Is this the correct answer? No; the correct answer is 46.9 m 2 . The correct answer must be rounded down so there is just one digit to the right of the decimal point. That's because the answer cannot have more digits to the right of the decimal point than any of the original measurements. Using extra digits implies a greater degree of precision than actually exists. The correct number of digits is called the number of significant figures . To learn more about significant figures and rounding, you can watch the videos at the URLs below. Q: What two measurements are multiplied to find the area of a rectangle? Choices: - depth and width - volume and mass - length and depth - length and width A:

Ans:
length and width
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