Which Of The Following Statements About Cells Is True
Question: Which of the following statements about cells is true?
Answer: All cells have internal structures that move
Question: Light microscopes
Answer: use light and glass lenses to magnify an image.
Question: One centimeter = ________ millimeters.
Answer: 10
Question: Resolution is the
Answer: ability of an optical instrument to show two close objects as separate
Question: Which of the following statements about electron microscopes is true?
Answer: Electron microscopes focus electron beams to create a magnified image of an object
Question: A scientist wants to examine living cells lining the respiratory tract to determine how the cells use tiny hairs to move dirt and mucus away from the lungs. Which of the following instruments would be best, and why?
Answer: a light microscope, because it allows observations of whole, live cells
Question: The idea that all living things are composed of cells and that all cells come from other cells defines
Answer: cell theory.
Question: A scientist wants to magnify a pollen grain 8,000 times and examine the ridges and pores on its surface. Which one of the following instruments would be best?
Answer: a transmission electron microscope
Question: A scanning electron microscope is used to study ________, whereas a transmission electron microscope is used to study ________.
Answer: cell surfaces . . . internal cell structures
Question: The diameter of most animal and plant cells ranges from
Answer: 10 to 100 micrometers
Question: As cell size increases, the
Answer: volume increases faster than the surface area.
Question: Which of the following cells has the greatest surface-to-volume ratio?
Answer: bacterium
Question: A cell is exposed to a substance that prevents it from dividing. The cell becomes larger and larger. This situation
Answer: will eventually be problematic, since the cell's ability to absorb nutrients through its outer membrane will not keep increasing as quickly as its cytoplasmic needs
Question: Your throat is dry, and you want the last cough drop in the box to last a long time in your mouth. What should you do?
Answer: Keep the cough drop whole. This maintains the largest surface-to-volume ratio, and slows the dissolution of the cough drop.
Question: Archaea are composed of ________ cells.
Answer: prokaryotic
Question: Which of the following structures is exclusively associated with prokaryotic cells?
Answer: nucleoid
Question: The nucleoid region of a prokaryotic cell
Answer: contains the cell's DNA.
Question: ________ cells lack a membrane-enclosed nucleus.
Answer: Prokaryotic
Question: A bacterial cell's DNA is found in its
Answer: nucleoid region.
Question: Which of the following structures are used by prokaryotes for attaching to surfaces
Answer: both pili and capsules
Question: The membranous compartmentalization of a cell
Answer: allows different metabolic processes to occur simultaneously.
Question: Which of the following statements about internal membranes in eukaryotic cells is false?
Answer: In eukaryotic cells, internal membranes standardize the internal environment of all cellular organelles.
Question: You are told that the cells on a microscope slide are plant, animal, or bacterial. You look at them through a microscope and see cell walls and membrane-bound organelles. You conclude correctly that the cells
Answer: are plant cells
Question: Unlike animal cells, plant cells have ________ and ________. Unlike plant cells, animal cells have ________.
Answer: chloroplasts . . . cell walls . . . centrioles
Question: Which of the following statements about cellular metabolism is false?
Answer: Cellular metabolism occurs in animal but not plant cells
Question: Plasma membranes are permeable to
Answer: nonpolar molecules such as CO2.
Question: What would you expect to find when looking through a SEM at a cell treated with an enzyme that cleaves proteins at their hydrophilic amino acids?
Answer: a cell surface that is devoid of any major structures
Question: The nucleus of a cell
Answer: contains DNA.
Question: Long fibers of DNA and protein are called
Answer: chromatin.
Question: During cell reproduction, chromatin fibers coil up into structures called
Answer: chromosomes.
Question: The function of the nucleolus is
Answer: to manufacture ribosomal RNA.
Question: Protein synthesis requires the use of mRNA, which
Answer: is translated by the ribosomes into the amino acid sequences of proteins.
Question: The plasma cell produces thousands of antibodies per second. What type of intracellular structure would you expect to be very prominent within the cell?
Answer: endoplasmic reticulum
Question: Which location in the cell is unlikely to contain ribosomes or ribosomal subunits?
Answer: plasma membrane
Question: Which of the following statements regarding the endomembrane system is false?
Answer: The endomembrane system is a system of interrelated membranes that are all physically connected
Question: The endomembrane system includes all of the following organelles except the
Answer: peroxisome
Question: Smooth endoplasmic reticulum
Answer: stores calcium ions in muscle cells
Question: The two main functions of the rough endoplasmic reticulum are the production of
Answer: membrane and proteins secreted by the cell.
Question: Secretory proteins are
Answer: released from the cell through the plasma membrane.
Question: The cells that produce hair contain a lot of ________, while the cells that produce the oils that coat the hair contain a lot of ________.
Answer: rough endoplasmic reticulum . . . smooth endoplasmic
Question: The Golgi apparatus
Answer: stores, modifies, and packages proteins
Question: Which of the following statements regarding the Golgi apparatus is false?
Answer: The Golgi apparatus decreases in size when a cell increases its protein production
Question: Which of the following statements about lysosomes is false?
Answer: Lysosomes synthesize proteins from the recycled amino acids
Question: When a cell is deprived of oxygen, its lysosomes tend to burst and release their contents into the cell. As a result of this, that cell will
Answer: undergo self-digestion and die
Question: Tay-Sachs disease results from the malfunction of
Answer: lysosomes
Question: Tay-Sachs disease
Answer: causes an accumulation of lipids in brain cells.
Question: Which of the following statements about the functions of a plant cell central vacuole is false
Answer: The central vacuole of a plant cell may digest chemicals for recycling
Question: Contractile vacuoles
Answer: prevent cells from bursting as a result of the influx of excess water.
Question: A manufacturing company dumps its wastes into a nearby pond. One of the wastes is found to paralyze the contractile vacuoles of certain protists. A biologist looking at individual samples of these organisms taken from the pond would find that they
Answer: have gained water and burst.
Question: Which organelle is involved in the catabolism of fatty acids and the detoxification of alcohol
Answer: peroxosome
Question: Insulin is a protein that is produced by pancreatic cells and secreted into the bloodstream. Which of the following options correctly lists the order of the structures through which insulin passes from its production to its exit from the cell
Answer: rough ER, transport vesicles, Golgi apparatus, transport vesicles, cell membrane
Question: The function of mitochondria is
Answer: cellular respiration.
Question: Cyanide inhibits mitochondrial function; as a result, the rate of
Answer: ATP synthesis decreases
Question: The ________ of a mitochondrion is/are an adaptation that increases the surface area and enhances a mitochondrion's ability to produce ATP.
Answer: cristae
Question: The function of chloroplasts is
Answer: photosynthesis.
Question: The stroma is the
Answer: thick fluid enclosed by the inner chloroplast membrane
Question: Mitochondria differ from chloroplasts in that mitochondria
Answer: contain membrane folds called cristae, whereas chloroplasts contain disk-like vesicles in stacks called grana
Question: The endosymbiosis hypothesis proposes that
Answer: a small cell lived inside a larger cell to the benefit of both cells
Question: The endosymbiosis hypothesis is supported by all of the following pieces of evidence, except the fact that
Answer: mitochondria synthesize glucose like prokaryotes
Question: Microfilaments differ from microtubules in that microfilaments
Answer: are mainly composed of actin, whereas microtubules are composed of tubulin.
Question: Which of the following statements about the cytoskeleton is false
Answer: Once laid down, the elements of the cytoskeleton are fixed and remain permanently in place
Question: Intermediate filaments
Answer: surround the nucleus.
Question: A drug that interferes with microtubule formation is likely to completely disrupt
Answer: the movements of sperm cells.
Question: Cilia differ from flagella in that
Answer: cilia are typically more numerous and shorter than flagella.
Question: A basal body is
Answer: similar in structure to centrioles.
Question: Dynein arms
Answer: are found on microtubules in cilia and flagella and cause movement by grabbing and pulling at adjacent microtubule doublets.
Question: A woman is having trouble becoming pregnant. Examination of her partner's sperm indicates that dynein arms are missing from the flagella in his sperm cells. A physician explains that this could interfere with fertility by
Answer: preventing the sperm from swimming to the egg cell
Question: Decreased fertility in men from developed countries may be related to
Answer: increased exposure to hormone-like chemicals in the environment
Question: Most animal cells are
Answer: embedded in an extracellular matrix
Question: Most cells from multicellular organisms must be attached to their surroundings via integrins. Failure to maintain this contact will usually result in
Answer: the death of the cell
Question: Which of the following would be most affected by a mutation that prevented cells from forming tight junctions?
Answer: Which of the following would be most affected by a mutation that prevented cells from forming tight junctions? integrity of the inner lining of the digestive tract
Question: Skin cells are attached to the extracellular matrix by
Answer: anchoring junctions
Question: It is essential for heart muscle cells to beat in a coordinated fashion. The cell junctions that would best facilitate this are
Answer: communicating junctions.
Question: Which of the following statements about plant cell walls is false?
Answer: Plant cell walls protect plant cells by forming an impermeable layer around the cell.
Question: Which of the following statements regarding plasmodesmata is false?
Answer: Plasmodesmata are commonly found in single-celled organisms.
Question: Which of the following cell structures is associated with the breakdown of harmful substances or substances that are no longer needed by the cell?
Answer: peroxisomes
Question: Which of the following statements regarding cells is false?
Answer: All cells have a cell wall.
Question: A child dies following a series of chronic bacterial infections. At the autopsy, the physicians are startled to see that the child's white blood cells are loaded with vacuoles containing intact bacteria. Which of the following explanations could account for this finding?
Answer: A defect in the lysosomes of the white blood cells prevented the cells from destroying engulfed bacteria.
Question: The oil from the sebaceous glands is produced by which of the following cell organelles?
Answer: smooth endoplasmic reticulum