Mastering Biology: Chapter 6
The nuclear lamina is an array of filaments on the inner side of the nuclear membrane. If a method were found that could cause the lamina to fall into disarray, what would you most likely expect to be the immediate consequence?
a change in the shape of the nucleus
Which organelle or structure is absent in plant cells?
centrosomes
Which structure is NOT part of the endomembrane system?
chloroplast
Which structure is not part of the endomembrane system?
chloroplast
What are the three organelles that plant cells have but animal cells do not?
chloroplast, central vacuole, cell wall
Thylakoids, DNA, and ribosomes are all components found in _____.
chloroplasts
Approximately how much additional cytoplasm will the budding cell have to synthesize as it grows to the size of the mature cell?
19 µm^3
Approximately how much additional area of plasma membrane will the budding cell have to synthesize as it grows to the size of the mature cell?
22 µm^2
What is the approximate surface area of the budding cell? (Remember that you approximated the diameter of the budding cell to be 3 µm.)
28 µm^2
What is the approximate diameter of the budding cell?
3 µm
What is the approximate volume of the mature parent cell?
33 µm3
The Golgi apparatus has a polarity, or sidedness, to its structure and function. Which of the following statements correctly describes this polarity?
Proteins in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. Transport vesicles fuse with one side of the Golgi and leave from the opposite side.
Which of the following statements correctly describes some aspect of protein secretion from prokaryotic cells?
Proteins secreted by prokaryotes are synthesized on ribosomes bound to the cytoplasmic surface of the plasma membrane.
Which one of the following statements about the endomembrane system is correct?
Proteins that will be secreted from the cell are likely to be found in closed spaces bounded by membranes of the endomembrane system.
_____ are the sites of protein synthesis.
Ribosomes
What path does a protein in the secretory pathway take, starting from its site of synthesis?
Rough ER, Golgi apparatus, secretory vesicles, 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.
Which of the following is a function of the central vacuole?
Storing compounds produced by the cell
What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane?
Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores.
Choose the best description of the cell cytoskeleton.
The cell cytoskeleton is a dynamic network of fibers that can be quickly dismantled and reassembled to change cell shape and the position of cell components.
Which of the following describes the function of the chloroplast?
The chloroplast converts light energy to chemical energy.
During a pulse-chase experiment, photographic emulsions were prepared at different times during the chase, and radioactive spots were detected at the following times and locations: 5 minutes: rough ER; 10 minutes: Golgi apparatus; 40 minutes: endosomes; 70 minutes: lysosomes; 140 minutes: lysosomes. Which of the following conclusions can be drawn from these results?
The final destination of the proteins was the lysosome.
Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why?
The intestinal cells are bound together by tight junctions.
Which of the following structures is found in animal cells but NOT in plant cells?
centrioles
Drag each cell structure to the appropriate bin.
*Only bacteria and archaea have prokaryotic cells, which lack a nucleus and other membrane-enclosed organelles. Prokaryotic cells are smaller and, at the level of the individual cell, are generally less versatile than eukaryotic cells, which compartmentalize many of their metabolic pathways into organelles. Nevertheless, prokaryotes are indispensable in every known ecosystem, and certain species are capable of surviving in some of the harshest and most nutrient-limiting environments on Earth.
Drag each cell structure to the appropriate bin. If a structure is found in both plant cells and animal cells, drag it to the "both" bin.
*Plant cells and animal cells have more in common than they have differences. Nevertheless, plant cells' unique structures play important roles. Photosynthesis occurs in plant cells' chloroplasts. The plant cell's central vacuole takes up most of the space within the cell and serves a variety of functions, including storage and hydrolysis of organic compounds. Plant cell walls, which are composed primarily of cellulose, protect the cells from damage and maintain their shape. Cellulose is the most abundant organic compound on the planet.
Which statements are true for chloroplasts? Select the three that apply.
*The chloroplast and the chemical reactions associated with it are extremely important for all living things. The photosynthetic reactions are responsible for converting solar energy into chemical energy that is used not only by the cells in which photosynthesis occurs but also by other organisms. For example, all of the foods you eat can be traced back to a plant or other photosynthetic organism. Furthermore, the chloroplast and its reactions have had a profound influence on the constitution of Earth's atmosphere due to the fact that oxygen is a byproduct of photosynthesis.
Drag each function to the appropriate bin.
*The endomembrane system is critical for the synthesis, processing, and movement of proteins and lipids in the cell. The smooth ER functions mainly in lipid synthesis and processing. The rough ER is the site of secretory protein synthesis. These proteins are processed further in the Golgi apparatus, from where they are dispatched in vesicles to the plasma membrane. Lysosomes, whose enzymes and membranes are made and processed by the rough ER and Golgi apparatus, function in the hydrolysis of macromolecules, such as in phagocytosis and autophagy.
1 meter = _____ centimeters.
100
The diameter of a typical eukaryotic cell is approximately ten times the diameter of a typical prokaryote. What is the ratio of the volume of typical eukaryotic:prokaryotic cells?
1000:1
What is the approximate volume of the budding cell?
14 µm^3
Note that the scale bar under the photo is labeled 1 μm (micrometer). The scale bar works the same way as a scale on a map, where, for example, 1 inch equals 1 mile. In this case the bar represents a much smaller distance. What is the approximate diameter of the mature parent cell?
4 µm
What is the approximate surface area of the mature parent cell? (Remember that you approximated the diameter of the mature parent cell to be 4 µm.)
50 µm^2
Which of these structures stores, modifies, and packages products?
A
Prokaryotes are classified as belonging to two different domains. What are the domains?
Bacteria and Archaea
_____ is/are identical in structure to centrioles.
Basal bodies
Which of the following statements correctly describes a common characteristic of a plant cell wall and an animal cell extracellular matrix?
Both are permeable to water and small solutes.
Which of the following are common traits of chloroplasts and mitochondria?
Both have their own DNA.
Choose the letter that indicates the organelle that contains most of a cell's DNA.
C
The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter _____.
C
Which of the following is a major difference between prokaryotic cells and eukaryotic cells?
Eukaryotic cells have more intracellular organelles than prokaryotes.
Pancreatic cells, which secrete a large amount of digestive enzymes, are labeled with radioactive leucine and then chased for several hours with nonradioactive leucine. Photographic emulsions are prepared at different times during the chase. Where would the black spots appear on an emulsion prepared 3 hours after the pulse?
Exterior of the cell
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 surface area-to-volume ratio which facilitates the exchange of materials between a cell and its environment.
Which of the following statements is true about cell fractionation?
Cell fractionation separates cells into their component parts.
_____ are found only in plant cells, but _____ are found in both plant and animal cells.
Central vacuoles; ribosomes
Which of the following statements about chloroplasts and mitochondria is true?
Chloroplasts and mitochondria synthesize some of their own proteins.
Which statement about the cytoskeleton is true?
Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm.
The DNA-containing region of this bacterial cell is indicated by the letter _____.
D
Which of these provides the cell with structural support?
D
Which molecules do not normally cross the nuclear membrane?
DNA
A cell has formed a food vacuole as it ingested a food particle. Which of the following events is associated with the breakdown of that food particle?
Digestion of the food particle occurs in a vesicle enclosed by a membrane that separates the digestion from the cytoplasm.
Which of these is the double membrane that encloses the nucleus?
E
What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?
ER → Golgi → vesicles that fuse with plasma membrane
What is the reason that a modern transmission 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?
Electron beams have much shorter wavelengths than visible light.
In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells?
Eukaryotic cells are compartmentalized, which allows for specialization.
True or false? Large proteins containing a nuclear localization signal (NLS) bind to the nuclear pore and enter the nucleus without any expenditure of energy.
False
True or false? Proteins produced during the "chase" phase of a pulse-chase experiment are labeled with radioactive material.
False
_____ are surface appendages that allow a bacterium to stick to a surface.
Fimbriae
_____ aid in the coordination of the activities of adjacent animal cells.
Gap (communicating) junctions
Microtubules and microfilaments commonly work with which of the following to perform many of their functions?
Golgi apparatus
Which of the following is part of the endomembrane system?
Golgi apparatus
Which of the following produces and modifies polysaccharides that will be secreted?
Golgi apparatus
A mutation that disrupts the ability of an animal cell to add polysaccharide modifications to proteins would most likely cause defects in its _____.
Golgi apparatus and extracellular matrix
What is the first step in a pulse-chase experiment?
Incubating cells with a labeled molecule
Which statement about extracellular structures (plant cell walls and the extracellular matrix of animal cells) is correct?
Information can be transmitted from these extracellular structures to the cytoplasm.
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 functions is NOT associated with the cytoskeleton in eukaryotic cells?
Movement of RNA molecules from the nucleus to the cytoplasm
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.
What scientific hypotheses can be tested by a pulse-chase experiment?
Movement of molecules through a cell over time
Nucleoplasmin is a nuclear protein. This protein was divided into two segments and linked to the same large cytoplasmic protein, generating two fusion proteins. After injecting these fusion proteins into a cell, one of the proteins was found in the nucleus and the other in the cytoplasm. Which of the following conclusions can be drawn from these results?
Only one of the two fusion proteins possesses a nuclear localization signal.
A small protein (molecular weight = 25,000 daltons) is injected into a cell and observed in the nucleus a short time later. What type of transport has taken place?
Passive transport
Select the correct statement describing cellular structure or function.
Plant and animal cells both carry out cellular respiration, producing ATP.
Which statement correctly describes an endomembrane function?
Products of the ER are usually modified during their transit from the cis to the trans region of the Golgi apparatus.
Gaucher disease is the most common of lipid storage diseases in humans. It is caused by a deficiency of an enzyme necessary for lipid metabolism. This leads to a collection 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 would 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 the cell-cell interaction (cell 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.
When the budding cell matures, it will be approximately how many times greater in volume and how many times greater in surface area than its current size?
The new cell will be approximately 2.4 times its current volume and 1.8 times its current surface area.
Which of the following statements about the nuclear envelope is false?
The nuclear envelope is continuous with the Golgi apparatus.
Which statement correctly describes the nuclear envelope of a eukaryotic cell?
The nuclear envelope is continuous with the endoplasmic reticulum.
Identify the correct statement about differences between rough and smooth endoplasmic reticulum (ER).
The outer surface of smooth ER lacks ribosomes, whereas the outer surface of rough ER has ribosomes.
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 is a characteristic common to all of these extracellular structures?
They are constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell.
In experiments to test whether a protein can enter the nucleus, why would proteins be labeled with fluorescent molecules?
To make the proteins easy to see
Cilia and flagella bend because of _____.
a motor protein called dynein
Drag the labels onto the diagram to identify the path a secretory protein follows from synthesis to secretion. Not all labels will be used.
a. ER b. cis Golgi cisternae c. medial Golgi cisternae d. trans Golgi cisternae e. plasma membrane
Can you label the structures of a plant cell?
a. central vacuole b. cell wall c. chloroplast d. Golgi apparatus e. smooth endoplasmic reticulum (ER) f. rough endoplasmic reticulum g. nucleus h. mitochondrion
Drag the labels to the appropriate locations in this diagram.
a. fimbriae b. nucleoid c. plasma membrane d. cell wall e. capsule f. flagella g. bacterial chromosome h. ribosomes
Drag the labels on the left onto the diagram of the animal cell to correctly identify the function performed by each cellular structure.
a. synthesize lipids b. asssembles ribosomes c. defines cell shape d. produces secretory proteins e. modifies and sorts proteins f. digest proteins g. generates ATP
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
Can you match these prefixes, suffixes, and word roots with their definitions?
across: trans- color: chrom- body: -some (or soma) water: aqu-(or aqua-) two: bi- little, small: -elle between: inter- inside, inner: endo- true, good: eu- cell: -cyte (or cyto-) green: chloro- without, lack of, not: a- (or an-) out of: ex- thread: mito- below, less than: hypo- leaf: -phyll eat: phago- same: sym- above, greater than: hyper- small: micro- formed substance: -plasm
In plant cells, the middle lamella _____.
allows adjacent cells to adhere to one another
All of the following are part of a prokaryotic cell EXCEPT _____.
an endoplasmic reticulum
Which of the following is NOT true? Both chloroplasts and mitochondria _____.
are part of the endomembrane system
Consider two cells with the same volume but with very different surface areas due to differences in their shapes. The cell with the larger surface area is likely to __________.
be involved in the rapid uptake of compounds from the cell's environment
Which of the following is most likely to receive a fabricated organ made from his own cells?
bladder cancer patient
If a fabricated windpipe is not receiving proper oxygen and nutrients, which of the following failed to properly regenerate?
blood vessels
Where do scientists obtain adult stem cells?
bone marrow
Which of the following is the simplest collection of matter that can live?
cell
Which of the following choices correctly matches a tool and its proper application?
cell fractionation to study the function of specific organelles
What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?
cell wall
Which of the following correctly matches an organelle with its function?
central vacuole ... storage
Plant cells have two energy-related organelles. ________________ harness light energy to create sugars and ________________ break down these sugars to create ATP.
chloroplasts; mitochondria
The _____ is composed of DNA and protein.
chromatin
Basal bodies are most closely associated with which of the following cell components?
cilia
Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?
components of the cytoskeleton
Where would you expect to find proteins involved with movement of structures within a cell?
cytoskeleton
The structural framework in a cell is the
cytoskeleton.
The primary role of _____ is to bind animal cells together.
desmosomes
Drag the labels to their appropriate locations in the table below. Use only pink labels for the pink targets. Labels may be used more than once.
desmosomes-animal gap junctions-animal tight junctions-animal plasmodesmata-plant cellulose-plant collagen-animal
Which organelles comprise the endomembrane system of a cell?
endoplasmic reticulum, Golgi apparatus, lysosome
The ____________________ builds compounds, whereas the ________________ breaks things down.
endoplasmic reticulum; lysosome
The evolution of eukaryotic cells most likely involved _____.
endosymbiosis of an aerobic bacterium in a larger host cellthe endosymbiont evolved into mitochondria
Ideally, the best scaffold for growing a replacement tissue or organ would be made of what?
extracellular matrix
Which of the following contain the 9 + 2 arrangement of microtubules, consisting of nine doublets of microtubules surrounding a pair of single microtubules?
flagella and motile cilia
The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by the _____.
function of the Golgi apparatus in sorting and directing membrane components
Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through _____.
gap junctions
Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells?
gap junctions
Amoebae move by crawling over a surface (cell crawling), which involves _____.
growth of actin filaments to form bulges in the plasma membrane
Chloroplasts and mitochondria are thought to be of prokaryotic origin. One piece of evidence that supports this hypothesis is that these organelles contain prokaryotic-like ribosomes. These ribosomes are probably most similar to ribosomes found __________.
in bacterial cells
Where are proteins produced other than on ribosomes free in the cytosol or ribosomes attached to the ER?
in mitochondria
Where would you expect to find tight junctions?
in the epithelium of an animal's stomach
In a plant cell, DNA may be found _____.
in the nucleus, mitochondria, and chloroplasts
Which of the following proteins are synthesized by bound ribosomes?
insulin lysosomal enzyme ER protein
The extracellular matrix is thought to participate in the regulation of animal cell behavior by communicating information from the outside to the inside of the cell via which of the following?
integrins
The plant cell wall
is a protective structure made of cellulose fibrils.
A researcher wants to film the movement of chromosomes during cell division. Which type of microscope should she choose and why is it the best choice?
light microscope, because the specimen is alive
The advantage of light microscopy over electron microscopy is that _____.
light microscopy allows one to view dynamic processes in living cells
Which organelle plays a role in intracellular digestion?
lysosome
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 phagocytize asbestos, but are not able to degrade it. As a result, asbestos fibers accumulate in _____.
lysosomes
Which of the following organelles breaks down worn-out organelles?
lysosomes
What carries instructions for making proteins from the nucleus into the cytoplasm?
mRNA
Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane?
mRNA
Which of the following categories best describes the function of the rough endoplasmic reticulum?
manufacturing
Which structure-function pair is mismatched?
microtubule; muscle contraction
The cilia and flagella of eukaryotic cells are composed of _____.
microtubules
Which of these are hollow rods that shape and support the cell?
microtubules
Drag the terms on the left to the appropriate blanks in the sentences on the right. Terms can be used once, more than once, or not at all.
microtubules intermediate filaments microtubules microfilaments intermediate filaments microfilaments
Cyanide binds with at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the _____.
mitochondria
Suppose a young boy is always tired and fatigued, suffering from a metabolic disease. Which of the following organelles is most likely involved in this disease?
mitochondria
Where in a cell is ATP made?
mitochondria
Which of the following structures is found in eukaryotic but NOT prokaryotic cells?
mitochondria
Cyanide binds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the
mitochondria.
The smallest cell structure that would most likely be visible with a standard (not super-resolution) research-grade light microscope is a _____.
mitochondrion
Which of these organelles carries out cellular respiration?
mitochondrion
Which organelle is the primary site of ATP synthesis in eukaryotic cells?
mitochondrion
Which structure is common to plant and animal cells?
mitochondrion
Which plant cell organelle converts chemical fuel into packets of chemical energy that can power the cell?
mitochonrion
Cilia and flagella move due to the interaction of the cytoskeleton with which of the following?
motor proteins
Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP (because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing?
motor proteins
Cytochalasin D is a drug that prevents actin polymerization. A cell treated with cytochalasin D will still be able to _____.
move vesicles within a cell
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
Where is a bacterial cell's DNA found?
nucleoid region
Ribosomal subunits are manufactured by the _____.
nucleolus
Where is the genetic information of the cell stored?
nucleus
Which of these organelles produces H2O2 as a by-product?
peroxisome
Which cell would be best for studying lysosomes?
phagocytic white blood cell
Based on these data, what is the most likely function of the cells in this experiment?
phagocytosis
Mitochondria are found in _____.
plant and animal cells
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 must be involved in this condition?
the lysosome
In a bacterium, we will find DNA in _____.
the nucleoid
Drag the correct description under each cell structure to identify the role it plays in the plant cell.
plant cell wall: strong, protective structure made from cellulose fibrils central vacuole: regulates cytoplasm composition, creates internal pressure, and stores cell compounds chloroplast: makes sugar by converting light energy into chemical energy mitochondrion: produces chemical energy (ATP) that can power the cell Golgi apparatus: modifies and packages proteins
The _____ is a selective barrier, regulating the passage of material into and out of the cell.
plasma membrane
The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.
plasma membrane
What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell?
plasma membrane
Animal cells are surrounded by a(n) ________________, whereas plant cells are also surrounded by a(n) ________________ .
plasma membrane; cell wall
Dye injected into a plant cell might be able to enter an adjacent cell through __________.
plasmodesmata
A cell with a predominance of free ribosomes is most likely _____.
primarily producing proteins in the cytosol
What is the function of a bacterium's capsule?
protection
Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
proteins
Which of the following is present in a prokaryotic cell?
ribosome
In a bacterium, where are proteins synthesized?
ribosomes
Which of the following organelles might be found inside other organelles?
ribosomes
One of the ways smooth endoplasmic reticulum (ER) differs from rough endoplasmic reticulum is that rough ER is covered by
ribosomes.
Which structure is the site of the synthesis of proteins that may be exported from the cell?
rough ER
Which of these manufactures cellular membranes by adding membrane proteins and phospholipids to its own membrane?
rough endoplasmic reticulum
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
In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet is the _____.
size and weight of the component
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 ER
Where is calcium stored?
smooth endoplasmic reticulum
Where are lipids made in the cell?
smooth endoplasmic reticulum (ER)
What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?
standard light microscopy
Cell size is limited by _____.
surface to volume ratios
A cell with an extensive area of smooth endoplasmic reticulum is specialized to _____.
synthesize large quantities of lipids
In which of the following sites might protein synthesis occur in a typical eukaryotic cell?
the cytoplasm, the rough endoplasmic reticulum, and the mitochondria
A dish of animal cells was grown in the presence of radioactive phosphorous. The phosphorous largely ended up in nucleotides inside the actively growing animal cells. In which cellular structure or structures would you predict the majority of the radioactive phosphorous to accumulate?
the nucleus
In order to best eliminate the chance for rejection, a tissue or organ should be made from cells obtained from which of the following?
the patient
Which of the following is/are likely to limit the maximum size of a cell?
the shape of the cell the cell's surface-to-volume ratio the time it takes a molecule to diffuse across a cell
Which of these cell junctions form a barrier to the passage of materials?
tight junctions
In a liver cell detoxifying alcohol and some other poisons, the enzymes of the peroxisome remove hydrogen from these molecules and _____.
transfer the hydrogen to oxygen molecules to generate hydrogen peroxide
Beginning within the nucleus, the first step leading to the synthesis of a polypeptide is _____.
transferring of information from DNA to messenger RNA
Cells require which of the following to form cilia or flagella?
tubulin
Which organelle often takes up much of the volume of a plant cell?
vacuole
Which of the following clues would tell you if a cell is prokaryotic or eukaryotic?
whether or not the cell is partitioned by internal membranes
