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| 1 |  |  A cell can be divided into three principal parts: the cell (plasma) membrane, the cytoplasm and organelles, and the nucleus. |
|  | A) | True |
|  | B) | False |
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| 2 |  |  The cell membrane is also known as the plasma membrane. |
|  | A) | True |
|  | B) | False |
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| 3 |  |  The cytoplasm is the fluid portion of the cytosol. |
|  | A) | True |
|  | B) | False |
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| 4 |  |  The membrane is not solid, the phospholipid and protein molecules are free to move laterally in a constantly changing mosaic pattern—often referred to as the fluid-mosaic model of membrane structure. |
|  | A) | True |
|  | B) | False |
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| 5 |  |  The uptake of cholesterol molecules by cells lining an arterial blood vessel is an example of endocytosis. |
|  | A) | True |
|  | B) | False |
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| 6 |  |  In the process of endocytosis, secretory vesicles fuse with the cell membrane and release their contents into the extracellular environment. |
|  | A) | True |
|  | B) | False |
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| 7 |  |  In the human body, cilia are found along the basal surface of epithelial cells (the surface facing the lumen, or cavity) of the respiratory and female reproductive tracts. |
|  | A) | True |
|  | B) | False |
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| 8 |  |  In the human body, cilia and flagella are composed of protein microtubules arranged in a characteristic "9 + 2" pattern. |
|  | A) | True |
|  | B) | False |
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| 9 |  |  The jellylike matrix within a cell is known as the cytoskeleton. |
|  | A) | True |
|  | B) | False |
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| 10 |  |  The cytoskeleton is composed of protein fibers called microtubules and microfilaments, arranged in a complex flexible and mobile latticework. |
|  | A) | True |
|  | B) | False |
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| 11 |  |  Autophagy is a process involving lysosomes that destroy worn-out organelles so that they can be continuously replaced—also characterized as the "digestive system" of the cell. |
|  | A) | True |
|  | B) | False |
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| 12 |  |  Many more mitochondria are found in the ovum (egg cell) compared to sperm; and contain a more primitive form of DNA molecules that can transmit genetic defects from mother to child. |
|  | A) | True |
|  | B) | False |
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| 13 |  |  Most, if not all, organelles in the cell have a limited life span, and thus must be continuously destroyed and replaced. |
|  | A) | True |
|  | B) | False |
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| 14 |  |  Smooth endoplasmic reticulum would be abundant in cells that are active in protein synthesis and secretion, such as those of many exocrine and endocrine glands. |
|  | A) | True |
|  | B) | False |
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| 15 |  |  The phenomenon of "tolerance" to certain substances such as alcohol and certain drugs may be accompanied by increased amounts of the rough endoplasmic reticulum, particularly in liver cells. |
|  | A) | True |
|  | B) | False |
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| 16 |  |  Mitochondria may be able to reproduce themselves, especially in cells that require greater than normal energy outputs. |
|  | A) | True |
|  | B) | False |
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| 17 |  |  Small molecules may pass through the nuclear pore complexes located along the nuclear envelope by simple diffusion, but movement of larger protein and RNA molecules is a selective, energy-requiring process. |
|  | A) | True |
|  | B) | False |
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| 18 |  |  The expression of genes occurs in two sequential stages: first, genetic transcription and then, genetic translation. |
|  | A) | True |
|  | B) | False |
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| 19 |  |  Nucleoli are dark regions within the nucleus that contain DNA and code for the production of ribosomal RNA (rRNA). |
|  | A) | True |
|  | B) | False |
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| 20 |  |  Although DNA is the largest molecule in the cell, it has a simpler structure than that of most proteins. |
|  | A) | True |
|  | B) | False |
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| 21 |  |  According to the law of complementary base pairing, the number of purine bases in DNA molecules is greater than the number of pyrimidine bases in DNA. |
|  | A) | True |
|  | B) | False |
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| 22 |  |  Although composed of only four different types of bases, a gene extends several thousand nucleotides in length. |
|  | A) | True |
|  | B) | False |
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| 23 |  |  DNA is double-stranded helix, meaning there are two chains of DNA that twist about one another to form a molecule resembling a spiral staircase. |
|  | A) | True |
|  | B) | False |
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| 24 |  |  DNA strands spool around negatively charged histone proteins in the nucleus to form larger chromatin particles called nucleosomes. |
|  | A) | True |
|  | B) | False |
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| 25 |  |  Acetylation of chromatin is necessary for inactivating transcription by compacting the chromatin. |
|  | A) | True |
|  | B) | False |
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| 26 |  |  All types of RNA are formed from the information contained in the DNA within the nucleus. |
|  | A) | True |
|  | B) | False |
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| 27 |  |  Like DNA, RNA is also double-stranded. |
|  | A) | True |
|  | B) | False |
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| 28 |  |  The synthesis of RNA molecules from DNA is called genetic translation. |
|  | A) | True |
|  | B) | False |
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| 29 |  |  In the synthesis of RNA, the enzyme RNA polymerase is required to "unzip" a section of the paired DNA bases by breaking the weak hydrogen bonds and transcribing only one exposed strand of DNA. |
|  | A) | True |
|  | B) | False |
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| 30 |  |  The genes from DNA in the nucleolus located within the nucleus of the cell code for the specific production of transfer RNA (tRNA). |
|  | A) | True |
|  | B) | False |
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| 31 |  |  In humans, a pre-tRNA is produced that must be modified within the nucleus before it can enter the cytoplasm as tRNA and direct protein synthesis. |
|  | A) | True |
|  | B) | False |
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| 32 |  |  Segments of DNA scattered along a gene that do not participate in transcription of the genetic code, are called introns |
|  | A) | True |
|  | B) | False |
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| 33 |  |  Arriving in the cytoplasm, the mRNA can pass through a number of ribosomes to form a "string-of-pearls" structure called a polyribosome, or polysome, for short. |
|  | A) | True |
|  | B) | False |
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| 34 |  |  The sequence of three bases (a base triplet) in mRNA is called a codon, while the complementary triplet in tRNA is called an anticodon. |
|  | A) | True |
|  | B) | False |
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| 35 |  |  Proteins that are to be used within the cell are produced by the polyribosomes that float freely in the cytoplasm region of the cell. |
|  | A) | True |
|  | B) | False |
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| 36 |  |  Proteins that are synthesized for specific functions within a particular cell possess a hydrophobic leader sequence that permits the entry of these proteins into the cisterna of the rough endoplasmic reticulum. |
|  | A) | True |
|  | B) | False |
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| 37 |  |  A stack of several flattened sacs that receive, modify, and repackage proteins into new vesicles best describes the endoplasmic reticulum of the cell. |
|  | A) | True |
|  | B) | False |
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| 38 |  |  "Semiconservative" means only one of the two DNA strands is needed to synthesize pre-mRNA during transcription. |
|  | A) | True |
|  | B) | False |
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| 39 |  |  DNA helicase is responsible for unwinding the DNA molecule prior to DNA replication. |
|  | A) | True |
|  | B) | False |
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| 40 |  |  The non-dividing cell exists in a part of its life cycle known as interphase—which is subdivided into G1, S, and G2 phases. |
|  | A) | True |
|  | B) | False |
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| 41 |  |  The "S" phase of the cell cycle refers to the secretory phase of the cell. |
|  | A) | True |
|  | B) | False |
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| 42 |  |  A group of proteins known as the cyclins are active during different phases of the cell cycle. |
|  | A) | True |
|  | B) | False |
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| 43 |  |  Apoptosis refers to cell death during which the cell swells, ruptures its membranes, and burst. |
|  | A) | True |
|  | B) | False |
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| 44 |  |  Necrosis refers to cell death during which the cell swells, ruptures its membranes, and burst. |
|  | A) | True |
|  | B) | False |
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| 45 |  |  Capsases are enzymes that when activated stimulate apoptosis within a cell. |
|  | A) | True |
|  | B) | False |
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| 46 |  |  At the end of the G2 phase of the cell cycle, each chromosome consists of two strands called chromatids which are joined together by a centromere. |
|  | A) | True |
|  | B) | False |
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| 47 |  |  In anaphase of mitosis, the chromosomes line up single file along the equator of the cell. |
|  | A) | True |
|  | B) | False |
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| 48 |  |  The division of the cytoplasm during telophase is called cytokinesis. |
|  | A) | True |
|  | B) | False |
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| 49 |  |  During mitosis, the centrosomes organize contractile filaments that consist of actin and myosin that attach to the cell membrane and help pinch the mother cell into two identical daughter cells. |
|  | A) | True |
|  | B) | False |
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| 50 |  |  Growth due to an increase in cell number as a result of mitotic cell division is called hypertrophy. |
|  | A) | True |
|  | B) | False |
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| 51 |  |  Polycythemia is defined as an abnormal increase in the number of circulating red blood cells and therefore would be an example of hypertrophy. |
|  | A) | True |
|  | B) | False |
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| 52 |  |  Meiosis is also known as reduction division since the daughter cells contain twenty-three rather than forty-six chromosomes. |
|  | A) | True |
|  | B) | False |
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