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Test 2

Fill in the blanks.
  1. Movement of materials in and out of cells is controlled by the_________________.
  2. The sites of protein synthesis are______________________.
  3. Glycerol and fatty acids combine to form___________________.
  4. Breakdown of organic nutrients in cells to release energy and form ATP is called_________________.
  5. In a__________________reaction, smaller molecules are combined to form a larger molecule.
  6. The building units of proteins are____________________.
Choose the correct answer.
  1. Which of the following are functions of nucleic acids?
    1. They pass instructions from parents to offspring.
    2. They help make proteins.
    3. They contain instructions for proteins.
    4. all of the above.
  2. Types of lipids include:
    1. polysaccharides.
    2. amino acids.
    3. nucleotides.
    4. triglycerides.
  3. According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly
    1. spread in a continuous layer over the inner and outer surfaces of the membrane.
    2. confined to the hydrophobic interior of the membrane.
    3. embedded in a lipid bilayer.
    4. randomly oriented in the membrane, with no fixed inside-outside polarity.
  4. The molecule that is responsible for most functions of the plasma membrane is
    1. the phospholipid bilayer
    2. protein
    3. glycolipid
    4. cholesterol
  5. All of the following general functions are carried out by all cells except
    1. disposing of wastes
    2. maintaining integrity of the plasma membrane
    3. replacing cells through cell replication
    4. obtaining nutrients and chemical building blocks
  6. A transport protein requires ATP to pump sodium ions across a membrane. This is a case of
    1. passive transport
    2. active transport
    3. facilitated diffusion
    4. a and c
Answer the questions.
  1. What are some functions of membrane proteins?
  2. How do prokayoteic cells differ from eukaryotic cells?
  3. Which three organelles contain DNA?
  4. What is the chemical composition of a plant cell wall?

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