Term
| The process of RNA synthesis is called... |
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Definition
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Term
| Information in DNA is carried in... |
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Definition
the order of the nucleotide bases in one DNA strand. |
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Term
Correctly list the items in order of their relative sizes base pair nucleotide hemoglobin mRNA hemoglobin gene codon promoter ribosome chromosome |
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Definition
1. Nucleotide 2. Base Pair 3. Codon 4. Promoter 5. Hemoglobin mRNA 6. Hemoglobin gene 7. Ribosome 8. Chromosome |
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Term
| Both transcription and translation occur in three steps. What happens during the elongation step of each process? |
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Definition
During the elongation step of transcription, the RNA molecule is synthesized. During the elongation step of translation, the protein molecule is synthesized. |
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Term
The flow of genetic information in cells depends on specific base pairing between nucleotide. What is one type of base pairing in the process of translation? |
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Definition
| In translation, tRNA base-pairs with mRNA. |
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Term
| During DNA replication, a mistake was made in which an A was changed to a G. This kind of mutation is called a __________. |
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Definition
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Term
| The DNA sequence of a codon in a gene was changed from AAT to AAC. This type of mutation is called a __________. (Refer to Table 10-3 in your textbook.) |
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Definition
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Term
| The cells in your skin have a different shape and different function from the cells in your liver because the two types of cells have different __________. |
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Definition
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Term
| Which genes are expressed in a cell depends on the cell’s __________. |
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Definition
1. Histoy 2. Function 3. Environment |
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Term
Which is NOT a step at which gene expression can be regulated in eukaryotic cells?
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Definition
| the rate of DNA replication |
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Term
| In mammals, males have one X chromosome and one Y chromosome and females have two X chromosomes. How is the expression of genes on the X chromosome regulated so that there is equal expression of genes on the X chromosome in males and females? |
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Definition
| One X chromosome in females is inactivated so that females have only a single X chromosome capable of transcription. |
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Term
| Imagine that a codon in the template strand of a gene has the sequence TAC. What sequence of the anticodon would decode this codon? Explain your answer. |
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Definition
| UAC, because the anticodon has the same sequence as the template strand (but it has U instead of T) |
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Term
| Imagine that a probe sent to Mars brings back a sample that contains a very primitive life-form that appears similar to bacteria. Scientists are able to revive it and begin to grow it in culture. Much to their amazement, they discover that the organism has DNA and that the DNA encodes proteins. However, the DNA of these Martian microbes contains only two nucleotides, and these nucleotides contain bases that are not present in the DNA of organisms on Earth. If the Martian microbe uses triplet codons, what is the maximum number of different amino acids that it can have in its proteins? Explain. |
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Definition
| 7, because there are 8 possible codons (23 = 2 x 2 x 2 = 8) but at least one of the codons must be a stop. |
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Term
| Some people have eyes of two different colors. What is a possible explanation for this trait? |
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Definition
| During early stages of development, a mutation occurred in the cell that developed into one of the eyes, but not other cells in the embryo. |
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Term
| How did Beadle and Tatum use genetic mutations in strains of Neurospora as an investigative tool? |
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Definition
They crossed mutant strains that required a specific dietary supplement to survive with normal Neurospora. They tested the hypothesis that a specific region of DNA (genes) could somehow encode a specific enzyme. They showed that strains with a dietary supplement requirement were defective in one or another enzyme in the biochemical synthetic pathway for that supplement but never to more than one enzyme from the same biochemical pathway. |
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Term
| mRNA complementary to DNA is produced via __________. |
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Definition
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Term
| The "genetic code" includes __________. |
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Definition
units of three bases, each triplet (or codon) corresponding to a single amino acid specific base sequences in the nucleic acids that indicate where to "begin" and "end" the synthesis of a polypeptide |
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Term
| What is the promoter region? |
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Definition
| It is a region of a parent DNA strand that binds to the RNA polymerase and initiates transcription. See section 10.2.1 of your text. |
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Term
| what is the first step in translation? |
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Definition
| bases of the tRNA anticodon bind with the bases of the mRNA codon |
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Term
| Regulation of genetic expression __________. |
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Definition
| can be influenced by environmental conditions, including temperature changes | | | can occur at any point during replication, transcription, or translation and involves many, many different molecules |
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Term
| Cells produce molecules in a series of steps called __________ pathways. |
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Definition
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Term
Since DNA is in the nucleus, and protein synthesis takes place in the cytoplasm, there must be an intermediary that carries the DNA's message to the cytoplasm. This intermediary is called __________.
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Definition
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Term
__________ consist of three bases. Each of these either initiates or stops translation or specifies a particular amino acid in DNA translation.
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Definition
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Term
| Three codons tell protein synthesis to cease. These codons are called __________ codons. |
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Definition
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Term
RNA __________ is the molecule that is responsible for synthesizing each form of RNA.
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Definition
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Term
__________ is the type of RNA molecule that is created in the nucleus and then carries the genetic information to the cytoplasm.
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Definition
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Term
| What does mRNA carry from the nucleus? |
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Definition
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Term
Unripe black walnuts contain a compound, juglone, that inhibits RNA polymerase. With which process would juglone most likely interfere?
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Definition
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Term
If you were to create a drug that recognized and bound irreversibly to the promoter region of a specific gene, thereby blocking it, what effect would you expect that drug to have?
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Definition
| Both transcription and, eventually, translation of the gene would halt. |
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Term
What kind of point mutation would have the most dramatic effect on the protein coded for by that gene?
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Definition
| a base insertion near the beginning of the coding sequence |
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Term
| The codon that will be recognized by the anticodon GAU is __________. |
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Definition
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Term
| __________ is the specific kind of nucleic acid found in ribosomes. |
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Definition
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Term
| A mutation in which only one nucleotide in the DNA is changed is called a __________ mutation. |
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Definition
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Term
| One kind of mutation that has a high probability of affecting the final protein is a __________ mutation. |
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Definition
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Term
| In female mammals one X chromosome in each cell is inactivated, and the inactivated X forms a structure called a __________. |
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Definition
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Term
| Gene __________ is the production of the protein (or RNA) coded for by a gene. |
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Definition
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Term
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Definition
| is a specific segment of nucleotides in DNA |
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Term
What is a single-stranded molecule that contains the information for assembly of a specific protein?
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Definition
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Term
Anticodon is the term applied to
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Definition
| the part of the tRNA that interacts with the codon |
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Term
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Definition
| takes part indirectly in protein synthesis; the DNA itself stays in the nucleus |
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Term
Synthesis of a protein based on the sequence of messenger RNA
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Definition
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Term
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Definition
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Term
| correctly list the order of the stages during mitosis |
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Definition
| prophase, metaphase, anaphase, telophase |
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Term
| the following is NOT a function of mitosis in a multicellular organism |
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Definition
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Term
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Definition
| any cell or organism that is genetically identical to another |
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Term
| Alternate forms of a particular gene are called __________; they arise as a result of __________. |
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Definition
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Term
| Meiosis comes from a Greek word that means "to decrease." What decreases during the process of meiosis? |
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Definition
| the number of chromosomes |
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Term
| During the process of meiosis, DNA is replicated __________, followed by __________ nuclear divisions. |
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Definition
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Term
| During meiosis I, __________ separate; during meiosis II, __________ separate. |
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Definition
| homologous chromosomes, sister chromatids |
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Term
| Genetic recombination (crossing over) produces __________. |
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Definition
| new combinations of alleles |
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Term
| Sexual reproduction produces genetic diversity by __________. |
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Definition
fusing gametes to form the diploid organism. creating new combinations of alleles creating new combinations of homologous chromosomes |
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Term
| Imagine that you are looking at a eukaryotic cell in the microscope. When you examine the cell, you see that the nucleus is not present and that chromosomes are condensed and lined up independently in the center of the cell. What are the possible stages of division you might be observing in this cell? |
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Definition
| metaphase of mitosis or meiosis II |
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Term
| Imagine that you are looking at a eukaryotic cell in the microscope. When you examine the cell's nucleus, you see that the chromatin is spread uniformly through the nucleus—you cannot see chromosomes. Has the cell's DNA been replicated yet? Explain. |
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Definition
| You can't tell whether the DNA has replicated unless the DNA is condensed. |
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Term
| Which of the following chemicals would be potentially useful for treating cancer? |
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Definition
| a chemical that prevents DNA synthesis |
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Term
| Mating a male donkey to a female horse produces mules. Horses have 64 chromosomes and donkeys have 62 chromosomes. How many chromosomes do mules have? Why are they sterile? |
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Definition
| The mule has 63 chromosomes and is sterile because the chromosomes cannot pair properly at metaphase of meiosis I. |
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Term
| Which of the following describes something that is unique to meiotic cell division? |
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Definition
| Daughter cells contain half of the parental DNA. |
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Term
| To what does the term haploid refer? |
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Definition
| cells that contain only one of each type of chromosome |
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Term
| During what part of the cell cycle are chromosomes duplicated? |
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Definition
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Term
| If a diploid cell replicates its DNA so that it now contains an amount of DNA equal to 4n, how does a haploid gamete get a 1n number of chromosomes and a 1n amount of DNA? |
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Definition
| There are two meiotic divisions and four daughter cells produced in meiotic cell division. |
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Term
| What events are responsible for the genetic variability seen in meiosis? |
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Definition
| The direction in which a parental chromosome faces during metaphase I is random. | | | Homologous chromosomes exchange DNA with one another. |
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Term
| Prokaryotic cells divide by undergoing a process called __________. |
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Definition
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|
Term
Eukaryotic cells undergo a cellular division process called __________.
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Definition
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|
Term
Gametes are produced by a special cellular division process called __________.
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Definition
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|
Term
During mitosis, sister chromosomes are connected to each other at the __________.
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Definition
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|
Term
During metaphase, the paired chromatids are connected to opposite poles of the cell with structures called spindle __________.
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Definition
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Term
__________ are alternate forms of a given gene.
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Definition
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Term
Which of the following is a difference between sexual and asexual reproduction?
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Definition
| Asexual reproduction can occur more quickly than sexual reproduction. |
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Term
The specific place on a chromosome where a gene resides is called a(n) ___________.
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Definition
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Term
Which of the following would be an advantage of sexual reproduction?
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Definition
| Sexual reproduction promotes genetic variability, thereby increasing the probability that an individual with new combinations of favorable traits may arise. |
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Term
| What is the ultimate source of genetic variability in organisms? |
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Definition
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Term
The two ends of a eukaryotic chromosome are called __________.
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Definition
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Term
After a chromosome is duplicated, it consists of two __________ connected at the centromere.
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Definition
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Term
| If the diploid chromosome number of an organism is 24, its haploid chromosome number must be __________. |
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Definition
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Term
| The phase of meiosis during which chromosomes condense, and homologous chromosomes pair up is called __________. |
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Definition
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Term
| The phase of meiosis during which sister chromatids separate and move apart is called __________. |
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Definition
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Term
| The phase of meiosis during which chromosomes are lined up individually at the cell's equator is called __________. |
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Definition
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Term
| At which stage of mitosis are chromosomes arranged along a plane at the midline of the cell? |
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Definition
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|
Term
| A diploid cell contains in its nucleus |
|
Definition
| an even number of chromosomes |
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Term
| Synthesis of new DNA occurs during |
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Definition
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Term
| Which statement is most correct? |
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Definition
| Crossing over helps each gamete get a different set of alleles in meiosis. |
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Term
| When do homologous chromosomes pair up? |
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Definition
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Term
| Curiously, there is no crossing over of any chromosome in the male fruit fly Drosophila, which has four pairs of chromosomes. How many different combinations of maternal vs. paternal chromosomes are possible in a male fruit fly’s sperm? |
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Definition
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Term
| When a cell divides, what must it pass on to its offspring? |
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Definition
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Term
| Which of the following events occurs during the interphase portion of the eukaryotic cell cycle? |
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Definition
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|
Term
| During mitosis, sister chromosomes are connected to each other at the __________. |
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Definition
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Term
| Alleles are alternate forms of a gene. The alleles for the gene that determines blood type in humans are found at __________. |
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Definition
| the same locus on homologous chromosomes |
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Term
| Humans have about 35,000 genes. How many alleles of each of these genes are present in your muscle cells, disregarding genes on the X and Y chromosomes? |
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Definition
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Term
| If a plant is true-breeding for a flower color, it is __________ for the flower-color gene. |
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Definition
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Term
| A Punnett square is __________. |
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Definition
| a chart that can help you keep track of the alleles during genetic crosses |
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Term
| If a gene has alleles that are incompletely dominant, an individual that is heterozygous at this locus will have characteristics that are __________. |
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Definition
| intermediate between organisms that are homozygous for the recessive allele and organisms that are homozygous for the dominant allele |
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Term
| Which one of the following statements is true? (For extra practice, try to change the incorrect answers to make them correct statements. Also, give an example for each of the correct statements.) |
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Definition
| A single trait can be affected by many different genes. |
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Term
| Cystic fibrosis is a recessive trait. Imagine that your friend Roger has cystic fibrosis but that his parents do not. What do you know about Roger's alleles and those of his parents at the cystic fibrosis locus of their DNA? |
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Definition
| Roger is homozygous and his parents are heterozygous at the cystic fibrosis locus. |
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Term
| Anne Boleyn, King Henry VIII's second wife, was beheaded because she did not provide him with a son as an heir. Explain why King Henry should have blamed himself and not his wife. |
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Definition
| All of the eggs that females produce contain an X chromosome, so their genetic contribution to the child does not determine its sex. |
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Term
| In many cases, conditions that occur more frequently in males than in females are due to sex-linked inheritance. Male pattern baldness is more common in males than in females, but that is not because of sex-linked inheritance. Suggest a possible explanation. |
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Definition
| Male hormones affect expression of an important hair development gene. |
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Term
| Labrador retrievers may have yellow fur, chocolate brown fur, or black fur. Coat color is determined by two genes that have two alleles each. One gene, called E, determines whether the dog’s fur is dark or light, with the dark allele (E) dominant to the light allele (e). The other gene, called B, determines whether the dark fur will be black or chocolate, with the black allele (B) dominant to the chocolate allele (b). If you mate two chocolate labs together, what color puppies can they have? |
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Definition
| Chocolate or yellow puppies can be produced, because the parents can be either Eebb or EEbb. |
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Term
| A couple brings home their new, nonidentical twin daughters, Joan and Jill. After several months, the father begins to suspect that there was a mix-up at the hospital, because Jill doesn’t look much like either parent or like her sister. When the twins' blood tests come back, the father calls his lawyer to start a lawsuit against the hospital. The mother, father, and Joan have type A blood, but Jill has type O blood. Does the father have a case? Explain your answer. (The gene for blood type has three alleles: A, B, and O. The A and B alleles are codominant, and the O allele is recessive.) |
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Definition
| No, because parents with type A blood can have a child with type O blood. |
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Term
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Definition
| variations of the same gene (i.e., similar nucleotide sequences on homologous chromosomes) |
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Term
| Consider this hypothetical example: If you were to apply Mendel's reasoning to the past presidential election, and hanging chads (C) were dominant to pregnant chads (c), which of the following genotypes would result in the expression of the dominant phenotype from a cross of F1 offspring that are Cc? |
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Definition
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Term
| What does Mendel's law of independent assortment tell us about the behavior of genes during meiosis? |
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Definition
| Alleles of a particular gene will be distributed to gametes randomly, independent of other genes on different chromosomes. |
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Term
| If an organism has only three chromosomes, how many chromosomes are autosomes? |
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Definition
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Term
| A single gene capable of influencing multiple phenotypes within a single organism is said to be __________. |
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Definition
| pleiotropic for that gene |
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Term
| What is the root cause of sickle-cell anemia? |
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Definition
| mutations in the gene that directs the synthesis of the hemoglobin protein |
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Term
| If the pea plants I planted this year all have red flowers, and the parent of those seeds also had red flowers, those seeds are said to be __________. |
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Definition
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Term
| In Mendel's experiments, he first cross-bred true breeding purple-flowered peas with true breeding white-flowered peas. The first filial generation was found to consist entirely of __________-flowered pea plants. |
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Definition
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Term
| Mendel found that the F1 generation in his pea plant experiments looked like only one of the original parent plants, but that the flower color trait exhibited by the other parent showed up again in F2. He suggested that purple flower color was __________ with respect to flower color in peas. |
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Definition
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Term
| When one trait usually expresses itself in conjunction with another, and the genes which control that expression are found on the same chromosome, those two traits are genetically __________. |
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Definition
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Term
| Sometimes, chromosomes will exchange stretches of DNA during a crossing-over event. This occurs at a __________. |
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Definition
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Term
| When true breeding snapdragons with red flowers are cross-bred with true breeding white-flowered snapdragons, the progeny exhibit a color between white and red. This is because red and white have __________ dominance over each other. |
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Definition
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Term
| Which of the following can account for a situation where Mendel's Law of Independent Assortment fails to hold? |
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Definition
| The genes are on the same chromosome. |
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Term
| Some people are said to be "carriers" of genetic disorders. What does this mean? |
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Definition
| The individual is heterozygous for the disorder, and the allele for the disorder is recessive. |
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Term
| Which of the following is true of a man with hemophilia? |
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Definition
| The man inherited the hemophilia gene from his mother. |
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Term
| What happens if a baby has only one X chromosome, and no Y? |
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Definition
| This baby would be a female with Turner syndrome. |
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Term
| Which of the following is caused by an abnormal number of autosomes? |
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Definition
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|
Term
| Mendel's experiments with dihybrid crosses led him to develop his law of __________. |
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Definition
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Term
Geneticists study patterns of inheritance in human families to learn about genetic diseases. A chart showing how a trait is inherited over several generations of a family is called a __________.
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Definition
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Term
| Heterozygous individuals are __________ of recessive genetic disorders. |
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Definition
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Term
| Errors in meiosis that cause a gamete to have too few or too many chromosomes are called __________. |
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Definition
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Term
| A person with XO sex chromosomes has __________ syndrome. |
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Definition
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Term
| An organism is described as Rr:red. The Rr is the organism’s [A]; red is the organism’s [B]; and the organism is [C]. |
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Definition
| [A] genotype; [B] phenotype; [C] heterozygous |
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Term
| The 9:3:3:1 ratio is a ratio of |
|
Definition
| phenotypes in a cross of individuals that differ in two traits |
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Term
| A lawyer tells a male client that blood type cannot be used to his advantage in a paternity suit against the client because the child could, in fact, be the client’s, according to blood type. Which of the following is the only possible combination supporting this hypothetical circumstance? (Answers are in the order mother:father:child.) |
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Definition
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Term
| A heterozygous red-eyed female Drosophila mated with a white-eyed male would produce |
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Definition
| half red- and half white-eyed females as well as males in the F1 |
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Term
| Which is NOT true of sickle-cell anemia? |
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Definition
| It is lethal in heterozygotes because it is dominant. |
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Term
| Sex-linked disorders such as color blindness and hemophilia are |
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Definition
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Term
The sugars and phosphates in the "backbone" of a DNA strand are held together by ________.
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Definition
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Term
The two strands of a DNA double helix are held together by ________.
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|
Definition
| hydrogen bonds between bases on opposite DNA strands |
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Term
DNA structure can be described as a twisted ladder. Imagine you are climbing a model of DNA, just as if you were climbing a ladder. What parts of a nucleotide are your feet touching as you climb?
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Definition
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Term
Human chromosomes range in size dramatically, with the smallest (chromosome Y) being many times smaller than the largest (chromosome 1). What is responsible for determining the size of a chromosome?
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Definition
| the length of the DNA molecule in it |
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Term
Imagine that you are studying a newly discovered bacterium from a hot springs in Yellowstone National Park. When you examine the nucleotide composition of this organism, you find that 10% of the nucleotides in its DNA are adenine. What percentage of nucleotides are guanine? Explain.
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Definition
| 40%, because A pairs with T (accounting for 20% of the bases), leaving 80% of the nucleotides as G-C base pairs; half of 80 is 40. |
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Term
How can a cell, killed by heat in order to render it harmless, somehow still act to transform a second strain of bacterium from a noninfectious form into a disease carrier (i.e., a pathogen)?
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Definition
| The second (noninfectious) strain of bacterium was changed into a disease carrier (i.e., pathogen) by something from the heat-killed cell. |
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Term
Select the pairings of nucleotides determined by Chargaff's investigations.
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|
Definition
| thymine-adenine / guanine-cytosine |
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|
Term
To what does the phrase "ladder-like appearance" refer when considering the structure of DNA?
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Definition
| the complementary base pairs as rungs and the sugar-phosphate backbone as the rails |
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Term
Which of the following events occur within a DNA replication bubble?
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Definition
| DNA helicase unwinds the double helix at each replication fork within a replication bubble |
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Term
Which of the following options would result from the actions of DNA polymerase during DNA replication?
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Definition
| Two DNA polymerase molecules act to synthesize daughter DNA strands: one via a long continuous strand that moves in the same direction as the helicase, and a second polymerase synthesizes short segments of DNA that must be joined by ligase. |
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Term
What is the name Watson and Crick gave to the physical structure of DNA? __________
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Definition
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Term
__________ is the enzyme that splits the two original strands of DNA during replication.
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Definition
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Term
Rosalind Franklin and Maurice Wilkins used __________ to help discover the physical structure of DNA.
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Definition
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Term
As a DNA strand is duplicated, the newly created strand is called __________ to the original strand.
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Definition
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Term
__________ light is one of the listed causes for skin cancer (melanoma).
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Definition
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Term
Under normal circumstances, adenine will only be paired with __________ during DNA replication.
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Definition
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Term
Chromosomes are made of which of the following molecules?
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Definition
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Term
In Griffith's experiments, heating the S-strain bacteria killed them, but did not completely destroy their __________.
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Definition
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Term
| It is not the number of different nucleotides, but their __________ that is important in the ability of DNA to code for all the variability of organisms |
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Definition
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Term
Why did many scientists have trouble believing that DNA could be the carrier of genetic information?
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Definition
| DNA has only four nucleotides, which seemed too few to encode the vast array of hereditary traits of organisms. |
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Term
The process by which a parent cell that is going to divide synthesizes an exact copy of its DNA is known as __________.
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Definition
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|
Term
How many times is a cell's DNA replicated before it divides?
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Definition
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|
Term
What is the approximate error rate for DNA polymerase?
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|
Definition
| one error for every 10,000 bases added |
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|
Term
| What is the approximate error rate for DNA replication? |
|
Definition
| one error for every billion nucleotides |
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|
Term
Which of the following can cause errors to accumulate in DNA?
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|
Definition
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|
Term
Which of the following can be caused by ultraviolet radiation in sunlight?
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|
Definition
| Adjacent thymines become linked together. |
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Term
|
Definition
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|
Term
Because each base pairs with a complementary base, in every DNA molecule the amount of
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|
Definition
| cytosine equals that of guanine |
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|
Term
Semiconservative replication refers to the fact that
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|
Definition
| each parental DNA strand is joined with a new strand containing complementary base pairs |
|
|
Term
|
Definition
| cleaves hydrogen bonds that join the two strands of DNA |
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|
Term
|
Definition
| adds appropriate nucleotides to a newly forming DNA strand |
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|
Term
Which of the following are incorrectly matched?
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|
Definition
| complementary base pairs- adenine and cytosine |
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