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11 Cards in this Set
- Front
- Back
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Within a normal human somatic cell nucleus, there are:
a. 23 pairs of genes embodied within the chromosomes. b. 23 chromosomes composed of DNA c. 46 genes embodied within chromosomes. d. 46 chromosomes composed of DNA |
D - Every human somatic cell (meaning cells other than the gametes) has 46 chromosomes (23 pairs) in the nucleus. |
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Histones allow for:
a. Mixing of genetic material between and among gene segments b. Proper reproduction of chromosomes c. Enzyme synthesis within the nucleus d. efficient packaging of the nucleolus |
B - Since we have such long chromosomes, in order for them to accurately undergo reproduction they must be efficiently packed. |
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Histones are composed of:
a. RNA - Ribonucleic Acid b. Nitrogen and phosphate c. Base pairs d. Proteins |
D - Histones are proteins around which DNA is wrapped in its complex packaging structure |
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Nucleosome refers to :
a. Visible units of nucleotide bases b. Visible units of histone proteins c. Functional units of the Nucleolus d. Functional units of nuclear membrane |
B - Right before the cell divides, the eukaryotic cell's chromosomes wrap themselves tightly around their associated histones proteins. At that point the histones are visible as beadlike units called nucleosomes. |
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On one strand of a DNA molecule, units of the sugar-phosphate backbone are bound together by:
a. Dipole-dipole interactions b. Hydrogen bonds c. Phosphodiester Bonds d. Non-covalent bonds |
C - The DNA strand backbone is made of alternating unites of deoxyribose and phosphate, bound by a phosphdiester bond. |
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Adenine and Guanine are :
a. Purines b. Pyrimidines c. Histones d. Nucleosomes |
A - A & G are nitrogenous bases that belong to the purine category. Pyrimidines are C, U, and T. |
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Which of the following represents a correct base pairing within a DNA molecules?
a. Adenine - Guanine b. Adenine - Cytosine c. Cytosine - Thymine d. Thymine - Adenine
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D - In the formation of base pairs, a purine must go with a pyrimidine. Therefore, the only correct combination is that of T - A. |
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Matched bases within a base pair are linked by:
a. Nonpolar covalent bonds b. Polar covalent bonds c. Hydrogen bonds d. Ionic bonds |
C - Within the DNA molecule, matched bases are linked by hydrogen bonds. |
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Which of the following is true of DNA in a double helix?
a. It Is devoid of carbohydrates b. It consist of two complementary strands c. It's composed of phospholipids d. It is single stranded
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B - DNA in a double helix is a double stranded molecule, each strand is complementary to the other. |
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If one strand shows the DNA sequence " 5 - A G A T - 3, what will it's complementary strand show?
a. 3 - CCTA - 5 b. 3 - AAGA - 5 c. 3 - TCTA - 5 d. 3 - CTTG - 5 |
C - According to the DNA pairing rules, this would have to be the answer sine the purines have to match with a pyrimidine to make a complementary pair. |
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The variable region of DNA molecule carries?
a. Deoxyribose b. Purines and pyrimidines c. Histones d. nucleosomes |
B - The only section of the DNA that is variable carries purines and pyrimidines. A would be incorrect since it is an invariable section |
