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