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Questions and Answers
What is the first step in phospholipid synthesis?
What molecule is added to the glycerol-3-phosphate in steps 1 and 2 of phospholipid synthesis?
What is the role of CDP in step 3 of phospholipid synthesis?
Which nucleotide is used to help with the addition of the head group to phosphatidic acid?
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What is the role of flippase in phospholipid synthesis?
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Which of the following is NOT a step in phospholipid synthesis?
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Where does phospholipid synthesis primarily occur?
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What is the starting molecule for phospholipid synthesis?
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What is the role of SAM in phospholipid synthesis?
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What is the role of phosphatidylinositol in the cell membrane?
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Which class of lipids can be broken down structurally into two main classes?
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What are the three components of a phospholipid?
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Which phospholipid is much more common in the cell membrane?
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What is the basic structure of a phospholipid called?
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Which phosphoglyceride is not mentioned in the text?
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Which lipid contains a ceramide backbone?
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Which lipid can also be classified as a sphingolipid?
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What is the cellular location of phospholipid synthesis?
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How do phospholipids synthesized in the smooth ER reach the plasma membrane?
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What is the role of the transfer molecule CDP in phospholipid synthesis?
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Which step in cholesterol synthesis is catalyzed by HMG CoA reductase?
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How many acetyl CoA molecules are needed to make squalene in cholesterol synthesis?
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Which enzyme is the main regulatory step of cholesterol synthesis?
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Which molecule inhibits HMG CoA reductase in cholesterol synthesis?
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Which molecule activates HMG CoA reductase in cholesterol synthesis?
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What happens to the transcription of HMG CoA reductase gene when intracellular cholesterol levels are high?
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Which molecule promotes de-phosphorylation of HMG CoA reductase, activating the enzyme?
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Which molecule promotes phosphorylation of HMG CoA reductase, inhibiting the enzyme?
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What is the rate-limiting step in cholesterol synthesis?
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What is the final step in cholesterol synthesis?
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Which of the following is NOT a step in cholesterol synthesis?
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Which organs of the body contribute most significantly to cholesterol synthesis?
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Which structural group does cholesterol belong to?
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What is the role of the key regulatory enzyme HMG CoA reductase in cholesterol synthesis?
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What inhibits HMG CoA reductase in cholesterol synthesis?
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What is the cellular location of cholesterol synthesis?
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Which class of lipids can be broken down structurally into two main classes?
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What are the two main structural groups of lipids?
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What is the basic structure of a steroid called?
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What is the name for steroids with a hydroxy group at C3?
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Which cellular structure is formed from microtubules and rotates and moves in a whip-like fashion?
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Which molecular motors can move along microtubules and cause the whipping movements of cilia and flagella?
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Which type of intermediate filament confers stability and structure to muscle cells and some epithelial cells?
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Which type of filament is responsible for the shape of microvilli in an epithelial cell?
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Which type of filament is more stable and does not dissociate as readily as actin or tubulin?
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Which protein monomers are responsible for the formation of microtubules?
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What is the role of nucleating factors in the formation of F-actin?
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Which cellular structures are actin filaments strongly anchored to in a muscle cell?
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What is the main function of microfilaments in a fibroblast?
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What is the role of G-actin hydrolyzing ATP to ADP in the stability of F-actin?
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Which type of membrane protein is responsible for separating cells into apical and basal compartments?
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Which type of membrane protein is involved in providing structural integrity for a wide range of cells and tissues?
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Which type of membrane protein connects the cell membrane to important extracellular structures?
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Which type of junction contains a plaque and connects to microfilaments formed from actin?
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Which component of the cytoskeleton is responsible for cellular movement and organization of organelles?
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Which lipid component has an unbranched fatty acid tail with usually 16-18 carbons?
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What is the most common molecule linked to the phosphate head of glycerophospholipids?
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Which lipid intercalates between phospholipids and can impact membrane fluidity?
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Which lipid component has a sphingosine backbone and can decrease membrane fluidity due to its slightly different shape?
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Which membrane-bound components might have more cholesterol and/or sphingolipids, and why?
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Which of the following is a characteristic of a semi-permeable membrane?
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What is the most-used model of osmosis discussed in the text?
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What is the role of the Na+/K+ ATPase in the cell membrane?
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What is the concentration of Na+ in the extracellular fluid (ECF)?
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What is the main difference between passive transport and active transport?
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Which of the following is NOT a lipid component of the cell membrane?
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What is the function of the plasma membrane?
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What are the three main components of the cytoskeleton?
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What is the role of the Na+/K+ ATPase in maintaining cellular integrity?
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What is the function of the cell membrane in cell signaling?
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