AP Bio - Ch 06
Thylakoids, DNA, and ribosomes are all components found in ________.
chloroplasts
Which of the following organelles produces and modifies polysaccharides that will be secreted?
Golgi apparatus
Which structure below is independent of the endomembrane system?
chloroplast
Which of the following would be most appropriate method to observe and measure the size of ribosomes in a eukaryotic cell?
transmission electron microscopy
Cells require which of the following to form cilia or flagella?
tubulin
Which of the following will have the greatest ratio of surface area to volume?
A box that is 1×1×1.
Which domains of life are classified as prokaryotes?
Bacteria and Archaea
Both the volume and the surface area for three different cells were measured. These values are listed in the following table: (n/a) Using data from the table above, select the best explanation for why that cell will be able to eliminate waste most efficiently?
Cell 2, since it has the highest ratio of surface area to volume, which facilitates the exchange of materials between a cell and its environment.
Which organelle often takes up much of the volume of a plant cell?
central vacuole
What is the explanation for how a modern transmission electron microscope (TEM) can achieve a resolution of about 0.2 nanometers, whereas a standard light microscope has a maximum resolution of about 200 nanometers?
Electron beams have much shorter wavelengths than visible light.
Which of the following is a major difference between prokaryotic cells and eukaryotic cells?
Eukaryotic cells have membrane-bound organelles, while prokaryotic cells do not.
A mutation that disrupts the ability of an animal cell to add polysaccharide modifications to proteins would most likely cause defects in which of the following organelles or structures?
Golgi apparatus and extracellular matrix
What is the function of the nuclear pore complex found in eukaryotes?
It regulates the movement of proteins and RNAs into and out of the nucleus.
Which of the following statements about the cytoskeleton is true?
Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other.
Which of the following statements correctly describes some aspect of protein secretion from prokaryotic cells?
Proteins secreted by prokaryotes are likely synthesized on ribosomes bound to the cytoplasmic surface of the plasma membrane.
You have a cube of modeling clay in your hands. Which of the following changes to the shape of this cube of clay will decrease its surface area relative to its volume?
Round the clay up into a sphere.
Gaucher disease is the most common of lipid storage diseases in humans. It is caused by a deficiency of an enzyme necessary for the breakdown of lipids. This leads to the accumulation of fatty material in organs of the body including the spleen, liver, kidneys, lungs, brain, and bone marrow. Using your knowledge of the structure of eukaryotic cells, identify the statement below that best explains how internal membranes and the organelles of cells may be involved in Gaucher disease.
The lysosomes lack sufficient amounts of enzymes necessary for the metabolism of lipids.
H. V. Wilson worked with sponges to gain some insight into exactly what was responsible for holding adjacent cells together. He exposed two species of differently pigmented sponges to a chemical that disrupted intercellular junctions, and the cells of the sponges dissociated. Wilson then mixed the cells of the two species and removed the chemical that caused the cells to dissociate. Wilson found that the sponges reassembled into two separate species. The cells from one species did not interact or form associations with the cells of the other species. How do you explain the results of Wilson's experiments?
The molecules responsible for cell-cell adhesion (cell junctions) differed between the two species of sponge.
A newspaper ad for a local toy store indicates that an inexpensive toy microscope available for a small child is able to magnify specimens nearly as much as the more costly microscope available in your college lab. What is the primary reason for the price difference?
The toy microscope magnifies a good deal, but has low resolution and therefore poor quality images.
The cell walls of bacteria, fungi, and plant cells, and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following characteristics are common to all of these extracellular structures?
They are constructed of materials that are synthesized in the cytoplasm and then transported out of the cell for assembly.
The nuclear lamina is an array of intermediate filaments that line the inner side of the nuclear membrane. If a chemical treatment caused the lamina to disassemble, what would you expect to be the most likely immediate consequence?
a change in the shape of the nucleus
A newly discovered unicellular organism isolated from acidic mine drainage is found to contain a cell wall, a plasma membrane, two flagella, and peroxisomes. Based just on this information, the organism is most likely ________.
a motile eukaryote
Cilia and flagella bend because of ________.
a motor protein called dynein
Spherocytosis is a human blood disorder associated with a defective cytoskeletal protein in the red blood cells (RBCs). What do you suspect is the consequence of such a defect?
abnormally shaped RBCs
In a liver cell detoxifying alcohol and some other poisons, the enzymes of the peroxisome remove hydrogen from these molecules and ________.
combine the hydrogen with oxygen molecules to generate hydrogen peroxide
Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?
components of the cytoskeleton
The evolution of eukaryotic cells most likely involved ________.
endosymbiosis of an oxygen-using bacterium in a larger bacterial host cell-the endosymbiont evolved into mitochondria
A characteristic 9 + 2 arrangement of microtubules, consisting of nine doublets of microtubules surrounding a pair of single microtubules is associated with ________.
eukaryotic flagella and motile cilia
Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through ________.
gap junctions
In plant cells, the middle lamella ________.
glues adjacent cells together
Amoebae move by crawling over a surface (cell crawling), which involves ________.
growth of actin filaments to form bulges in the plasma membrane
Where are proteins produced other than on ribosomes free in the cytosol or ribosomes attached to the endoplasmic reticulum?
in mitochondria
If plant cells are grown on media containing radioactively labeled thymine for one generation, radioactively labeled macromolecules will be detected in which of the following?
in the nucleus, mitochondria, and chloroplasts
One primary advantage of light microscopy over electron microscopy is that ________.
light microscopy allows the visualization of dynamic processes in living cells
Asbestos is a material that was once used extensively in construction. One risk from working in a building that contains asbestos is the development of asbestosis caused by the inhalation of asbestos fibers. Cells will take up asbestos by phagocytosis, but are not able to degrade it. As a result, asbestos fibers accumulate in ________.
lysosomes
Which of the following macromolecules leave the nucleus of a eukaryotic cell through pores in the nuclear membrane?
mRNA
Cyanide binds with at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the bound cyanide is likely to be localized within the ________.
mitochondria
Which of the following is the smallest structure that would most likely be visible with a standard (not super-resolution) research-grade light microscope?
mitochondrion
Which organelle is the primary site of ATP synthesis in eukaryotic cells?
mitochondrion
Which structure is common to plant and animal cells?
mitochondrion
Researchers investigating the mechanism of vesicular transport assembled a cell-free system that included microtubule tracks, vesicles, and ATP. However, they observed no movement of transport of vesicles in this system. What were they missing?
motor proteins
Suppose a cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from ________.
nearly any eukaryotic organism
Which of the following structures form cytoplasmic channels that connect adjacent plant cells through the cell walls?
plasmodesmata
A cell with a predominance of rough endoplasmic reticulum is most likely ________.
producing large quantities of proteins for secretion
Examination of a cell by transmission electron microscopy reveals a high density of ribosomes in the cytoplasm. This observation suggests that this cell is actively producing large amounts of which of the following molecules?
proteins
Which of the following frequently imposes a limit on cell size?
ratios of surface area to volume
Which of the following is the most common pathway taken by a newly synthesized protein that will be secreted by a cell?
rough ER → Golgi → transport vesicle → plasma membrane
Which of the following macromolecules enter the nucleus of a eukaryotic cell through pores in the nuclear membrane?
ribosomal proteins
In the fractionation of homogenized cells using differential centrifugation, which of the following will require the greatest speed to form pellets at the bottom of the tube?
ribosomes
Which of the following are found in plant, animal, and bacterial cells?
ribosomes
Which of the following would be most appropriate method to observe the three-dimensional structure and organization of microvilli on an intestinal cell?
scanning electron microscopy
Vinblastine, a drug that inhibits microtubule polymerization, is used to treat some forms of cancer. Cancer cells given vinblastine would be unable to ________.
separate chromosomes during cell division
The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and, therefore, abundant in liver cells?
smooth endoplasmic reticulum
Which of the following would be the most appropriate method to observe the movements of condensed chromosomes during cell division?
standard light microscopy
A cell with a predominance of smooth endoplasmic reticulum is likely specialized to ________.
synthesize large quantities of lipids
Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large, complex, undigested lipids. Which cellular organelle is most likely defective in this condition?
the lysosome
In bacteria, DNA will be found in ________.
the nucleoid
A defect in which of the following intercellular junctions would allow partially digested material to leak passively between the cells of the small intestine into the abdominal cavity?
tight junctions
What is a primary function of integrins?
transmitting signals from the extracellular matrix to the cytoskeleton