38) In a plant cell, DNA may be found
A) only in the nucleus.
B) only in the nucleus and mitochondria.
C) only in the nucleus and chloroplasts.
D) in the nucleus, mitochondria, and chloroplasts.
E) in the nucleus, mitochondria, chloroplasts, and peroxisomes
18) Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
E) nucleic acids
5 Multiple Choice Questions
5 True/False Questions
35) Which plant cell organelle contains its own DNA and ribosomes?
D) Golgi apparatus
E) peroxisome → A
65) Which of the following makes it necessary for animal cells, although they have no cell walls, to have intercellular junctions?
A) Cell membranes do not distinguish the types of ions and molecules passing through them.
B) Large molecules, such as proteins and RNA molecules, do not readily get through one, much less two, adjacent cell membranes.
C) Cell-to-cell communication requires physical attachment of one cell to another.
D) Maintenance of tissue integrity and barriers to fluid leakage requires cells to adhere tightly to one another.
E) The relative shapelessness of animal cells requires a mechanism for keeping the cells aligned. → D
75) Which structure is common to plant and animal cells?
B) wall made of cellulose
C) central vacuole
E) centriole → B
What is the reason that a modern electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to tens of nanometers achievable for the best super-resolution light microscope?
A) The focal length of the electron microscope is significantly longer.
B) Contrast is enhanced by staining with atoms of heavy metal.
C) Electron beams have much shorter wavelengths than visible light.
D) The electron microscope has a much greater ratio of image size to real size.
E) The electron microscope cannot image whole cells at one time. → C
55) Which of the following statements about the cytoskeleton is true?
A) The dynamic aspect of cytoskeletal function is made possible by the assembly and disassembly of a large variety of proteins into complex aggregates.
B) Microfilaments are structurally rigid and resist compression, whereas microtubules resist tension (stretching).
C) Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other.
D) Chemicals that block the assembly of the cytoskeleton would cause little effect on the cell's response to external signals and stimuli.
E) Transport vesicles among the membranes of the endomembrane system produce the cytoskeleton. → B