| 1. |
________________ are organic molecules that have the function of
starting and regulating chemical reactions. |
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a) |
carbohydrates |
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b) |
lipids |
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c) |
enzymes |
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d) |
endoplasmic reticula |
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| 2. |
Amino acids are the building blocks of:
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a)
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DNA and RNA |
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b)
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lipids |
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c)
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proteins |
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d)
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carbohydrates |
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| 3. |
There are ________ different kinds of amino acids.
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a)
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20 |
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b)
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46 |
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c)
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100 |
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d)
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20,000-25,000 |
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| 4. |
The largest molecules in our bodies are:
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a)
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nucleic acids |
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b)
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chromosomes |
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c)
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proteins |
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d)
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amino acids |
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| 5. |
Which of the following statements is true?
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a)
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Each DNA molecule is a single gene. |
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b)
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DNA molecules are in the shape of a double helix.
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c)
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mRNA molecules are in the shape of a double helix.
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| 6. |
The human body is composed mostly of:
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a)
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calcium, iron, phosphorus, and zinc |
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b)
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oxygen, hydrogen, calcium, and iron |
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c)
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oxygen, nitrogen, hydrogen, and carbon |
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| 7. |
Which of the following statements is true about DNA?
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a)
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At the beginning of protein synthesis, a section of a DNA molecule unwinds and unzips.
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b)
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All of our DNA is normally located in the nucleus of our cells.
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c)
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DNA is composed of amino acids, phosphates, sugars, and bases.
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| 8. |
Which of the following statements is true about the protein
synthesis process? |
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a)
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When a section of a DNA molecule unwinds and unzips along its bases, a transfer RNA
forms by copying one side of the DNA. |
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b)
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The transfer RNA leaves the nucleus and goes out to the ribosomes in the cytoplasm
where proteins are assembled with the help of messenger RNA. |
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c)
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Both statements are false |
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| 9. |
Which of the following occurs at the ribosomes?
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a)
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Most of a cell's DNA molecules are stored there.
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b)
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Proteins are produced there. |
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c)
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mRNA are produced there. |
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| 10. |
Each tRNA anticodon has three bases. The three base combinations are
codes for attracting specific kinds of: |
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a)
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endoplasmic reticula |
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b)
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ribosomes |
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c)
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amino acids. |
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| 11. |
Which of the following statements is true about DNA replication?
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a)
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One DNA molecule becomes two identical ones as a result of this process.
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b)
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It occurs during meiosis but not mitosis. |
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c)
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It is part of the protein synthesis process.
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| 12. |
A DNA codon consists of:
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a)
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one nucleotide |
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b)
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three nucleotides |
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c)
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hundreds or even thousands of nucleotides |
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| 13. |
A gene is essentially a:
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a)
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sequence of many codons in a DNA molecule |
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b)
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single codon in a DNA molecule |
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c)
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chromosome |
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| 14. |
There are about 3 billion chemical base pairs in human DNA. Approximately
what percent of these base pairs actually code for genes?
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a)
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100% |
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b)
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30-50% |
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c)
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1-2% |
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| 15. |
Portions of DNA molecules that do not contain the
codes for proteins are called: |
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a)
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introns |
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b)
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exons |
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c)
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mutagens |
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| 16. |
Which of the following statements is true regarding the DNA code?
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a)
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Each of the 64 types of codons in DNA and RNA code for a different amino acid.
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b)
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Not all codons specify amino acid components to be included in a protein.
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c)
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DNA replication has a built-in mechanism that prevents or corrects all errors.
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| 17. |
The DNA code is: |
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a)
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unique to humans |
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b)
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found only in mammals |
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c)
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shared by all living things |
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