Chapter 6 Bio 1107

which of the following statements about chloroplasts and mitochondria is true? (eText Concept 6.5) * Chloroplasts and mitochondria are components of the endomembrane system. * Mitochondria but not chloroplasts contain a small amount of DNA. * Chloroplasts and mitochondria have three sets of membranes. * Chloroplasts and mitochondria synthesize some of their own proteins. * Chloroplasts but not mitochondria are completely independent of the cell of which they are a part.

Chloroplasts and mitochondria synthesize some of their own proteins.

Which of the following five membranes is most likely to have a lipid composition that is distinct from the other four? (eText Concept 6.5) * Golgi apparatus * mitochondrial outer membrane * endoplasmic reticulum * plasma membrane * lysosome membrane

mitochondrial outer membrane

Cilia and flagella move due to the interaction of the cytoskeleton with which of the following? (eText Concept 6.6) * tubulin * actin * motor proteins * mitochondria * pseudopodia

motor proteins

Which type of cell is most likely to have the most mitochondria? (eText Concept 6.5) * photosynthetic cells in the leaves of a tree * inactive yeast cells that are stored for future use * bacterial cells that are growing on sugars * muscle cells in the legs of a marathon runner * nondividing cells in the skin on your finger

muscle cells in the legs of a marathon runner Correct. Cellular respiration releases energy that cells need to carry out their functions. Active muscle cells need a lot of energy.

The observation that chloroplasts and mitochondria each contain their own DNA and synthesize some of the proteins that function in these organelles suggests that chloroplasts and mitochondria _____. (eText Concept 6.5) * are produced by the nucleus of the cell * contain two or more membranes * are part of the endomembrane system * must divide each time the cell containing them divides * are involved in energy metabolism of the cell

must divide each time the cell containing them divides

Which of the following is/are likely to limit the maximum size of a cell? (eText Concept 6.2) * the shape of the cell * the cell's surface-to-volume ratio * the time it takes a molecule to diffuse across a cell * All of the choices are correct. * None of the choices is correct.

All of the choices are correct.

Which of the following correctly compares the extracellular matrix (ECM) of animal cells to cell walls of plant cells? (eText Concept 6.7) * The structures that are external to the plasma membrane are essentially independent of the plasma membrane in both groups. * Both the ECM and the plant cell wall are composed of varying mixtures of proteins and carbohydrates. * Cell walls and ECMs provide for tight contact between adjacent cells. * The ECM and plant cell walls completely cover the plasma membrane of their respective cells. * Both the ECM and plant cell walls provide rigid structures that determine the shape of their respective cells.

Both the ECM and the plant cell wall are composed of varying mixtures of proteins and carbohydrates.

Which of the following is false in respect to cells' chromosomes? (eText Concept 6.3) * All cells possess one or more chromosomes. * Chromosomes are present throughout a cell's reproductive cycle. * Chromosomes only exist when cells are actively synthesizing proteins. * Chromosomes only appear as a cell is about to divide. * None of the listed responses is false.

Chromosomes only appear as a cell is about to divide.

Which statement about the cytoskeleton is true? (eText Concept 6.6) * Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm. * Microfilaments are more permanent structures in cells compared to intermediate filaments and microtubules. * Microtubules are chains of proteins that resist stretching. * Intermediate filaments are hollow tubes of protein that provide structural support. * Plant cells lack a cytoskeleton because they have a rigid cell wall.

Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm.

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? (eText Concept 6.2) * Eukaryotic cells can synthesize proteins but prokaryotic cells cannot. * Eukaryotic cells are much more successful than prokaryotic cells. * Eukaryotic cells lack many of the organelles found in prokaryotes. * Eukaryotic cells are compartmentalized, which allows for specialization. * Eukaryotic cells are larger than prokaryotic cells.

Eukaryotic cells are compartmentalized, which allows for specialization.

A researcher made an interesting observation about a protein made by the rough endoplasmic reticulum and eventually found in a cell's plasma membrane. The protein in the plasma membrane was actually slightly different from the protein made in the ER. The protein was probably altered in the _____. (eText Concept 6.4) rough endoplasmic reticulum transport vesicles plasma membrane smooth endoplasmic reticulum Golgi apparatus

Golgi apparatus No. The protein was originally synthesized on ribosomes of the rough ER, but modification occurs elsewhere.

Which of the following sequences represents the order in which a protein made in the rough endoplasmic reticulum might move through the endomembrane system? (eText Concept 6.4) * nuclear envelope#&8594;lysosome * Golgi apparatus#&8594;lysosome * lysosome#&8594;plasma membrane * plasma membrane#&8594;nuclear envelope * Golgi apparatus#&8594;mitochondria

Golgi apparatus#&8594;lysosome

Which of the following is false? (eText Concept 6.5) * Mitochondria have more than one membrane. * Mitochondria contain ribosomes in the intermembrane space. * Mitochondria are involved in energy metabolism. * The mitochondria possess their own DNA. * The folds of the inner mitochondrial membrane are called cristae.

Mitochondria contain ribosomes in the intermembrane space.

Microtubules and microfilaments commonly work with which of the following to perform many of their functions? (eText Concept 6.6) * lysosomes * ribosomes * Golgi apparatus * RNA * None of the listed responses is correct.

None of the listed responses is correct.

Which of the following is a possible reason for grouping the peroxisomes with chloroplasts and mitochondria? (eText Concept 6.5) * They all contain DNA and make some of their own proteins. * They all contain two or more membranes. * They are all part of the plastid family of organelles. * They are all involved in ATP synthesis. * None of these organelles are part of the endomembrane system.

None of these organelles are part of the endomembrane system.

What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane? (eText Concept 6.3) * The nucleolus contains messenger RNA (mRNA), which crosses the nuclear envelope through the nuclear pores. * Endoplasmic reticulum membrane is produced in the nucleolus and leaves the nucleus through the nuclear pores. * Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores. * The nuclear pores are connections between the nuclear membrane and the endoplasmic reticulum that permit ribosomes to assemble on the surface of the ER. * None of the listed responses is correct.

Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores. Correct. Proteins and ribosomal RNA are assembled into ribosomal subunits in the nucleolus.

Which of the following is/are possible site(s) of protein synthesis in a typical eukaryotic cell? (eText Concept 6.5) * the cytoplasm * the rough endoplasmic reticulum * in mitochondria * The first two answers are correct. * The first three answers are correct.

The first three answers are correct. Correct. Ribosomes are present in the cytoplasm, on the rough ER, and in mitochondria (and chloroplasts).

Which of the following statements correctly describes a common characteristic of a plant cell wall and an animal cell extracellular matrix? (eText Concept 6.7) * Both are permeable to water and small solutes. * Both are synthesized in the ER and Golgi apparatus. * Both are composed primarily of carbohydrates. * The first two answers are correct. * The first three answers are correc

The first two answers are correct. The ECM of animal cells is primarily glycoproteins—proteins with small carbohydrates attached.

Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why? (eText Concept 6.7) * The intestinal cells are bound together by gap junctions. * The intestinal cells are bound together by the extracellular matrix. * The intestinal cells are bound together by plasmodesmata. * The intestinal cells are fused together into one giant cell. * The intestinal cells are bound together by tight junctions.

The intestinal cells are bound together by tight junctions. Correct. The membranes of neighboring cells are actually fused at a tight junction, forming a seal that prevents the leakage of extracellular fluid across the layer of epithelial cells.

In addition to the fundamental structures required to be defined as a cell, a particular cell also has a nucleus and chloroplasts. Based on this information, this cell could be _____. (eText Concept 6.2) * a yeast (fungus) cell * a cell from the intestinal lining of a cow * a protistal cell and a plant cell * a bacterium * a cell from a pine tree

a protistal cell and a plant cell Correct. Some protists (e.g. algae) can photosynthesize and so do plants. As the protista and plants are both eukaryotes, they contain organelles.

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 _____. (eText Concept 6.2) * be involved in the rapid uptake of compounds from the cell's environment * be a prokaryotic cell * be nearly spherical in shape * have a very high metabolic rate * be buried deep in the interior of an organism

be involved in the rapid uptake of compounds from the cell's environment

Which of the following is the simplest collection of matter that can live? eText Overview * molecules * tissue * cell * organ * None of the listed responses is correct.

cell

Which of the following structures is found in animal cells but NOT plant cells? (eText Concept 6.6) * mitochondria * plasma membrane * Golgi apparatus * centrioles * rough endoplasmic reticulum

centrioles

Basal bodies are most closely associated with which of the following cell components? (eText Concept 6.6) * the central vacuole * mitochondria * nucleus * Golgi apparatus * cilia

cilia No. Basal bodies are made up of components of the cytoskeleton and are not associated with the nucleus.

Where would you expect to find proteins involved with movement of structures within a cell? (eText Concept 6.6) * muscles * ribosomes * cytoskeleton * plasma membrane * transport vesicles moving from the ER to the Golgi

cytoskeleton Correct. Movement of organelles and vesicles within cells is accomplished by the cytoskeleton.

Consider a protein that is made in the rough endoplasmic reticulum. You observe that when the synthesis of the protein is completed, the protein is located in the ER membrane. Where else in the cell might this protein be found? (eText Concept 6.4) * in the aqueous interior of a lysosome functioning as a digestive enzyme * in the cytoplasm functioning as an enzyme in carbohydrate synthesis * in the internal space of the Golgi apparatus, being modified before the protein is excreted * embedded in the plasma membrane functioning in the transport of molecules into the cell * in a mitochondrion functioning in ATP synthesis

embedded in the plasma membrane functioning in the transport of molecules into the cell

Which of the following organelles is unlikely to show enhanced abundance in pancreatic cells that secrete large amounts of digestive enzymes? (eText Concept 6.4) * free cytoplasmic ribosomes * Golgi apparatus * transport vesicles * rough endoplasmic reticulum * All of the listed responses will increase in pancreatic cells secreting digestive enzymes.

free cytoplasmic ribosomes

Which of the following is/are most likely to be involved in the process of producing proteins for a chloroplast or mitochondrion? (eText Concept 6.4) ** the Golgi apparatus * smooth endoplasmic reticulum * transport vesicles * rough endoplasmic reticulum * free cytoplasmic ribosomes

free cytoplasmic ribosomes No. The smooth ER is part of the endomembrane system; chloroplasts and mitochondria are not.

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell they _____. (eText Concept 6.2) * have no membrane-bounded organelles in their cytoplasm * lack a plasma membrane * lack chromosomes * have no ribosomes * have a smaller nucleus

have no membrane-bounded organelles in their cytoplasm

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 _____. (eText Concept 6.5) * free in the cytoplasm of eukaryotes * on the rough ER * in bacterial cells * The first two answers are correct. * The first three answers are correct.

in bacterial cells Correct. Like the ribosomes in bacteria, the ribosomes in the mitochondria are smaller than those found free in the cytoplasm or bound to endoplasmic reticulum in the eukaryotes

A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized _____. (eText Concept 6.4) * in the ribosomes of the mitochondria * on free cytoplasmic ribosomes * in the rough endoplasmic reticulum * in the smooth endoplasmic reticulum * in the plasma membrane

in the rough endoplasmic reticulum Correct. All of the membrane proteins of the endomembrane systems are made in the rough ER.

The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized _____. (eText Concept 6.7) * in the rough endoplasmic reticulum * externally to the plasma membrane * in the Golgi apparatus * in the smooth endoplasmic reticulum * in the rough endoplasmic reticulum and in the Golgi apparatus

in the rough endoplasmic reticulum and in the Golgi apparatus

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? (eText Concept 6.1) * transmission electron microscope, because of its high magnifying power * light microscope, because of its high resolving power * scanning electron microscope, because of its ability to visualize the surface of subcellular objects * transmission electron microscope, because of its high resolving power * light microscope, because the specimen is alive

light microscope, because the specimen is alive

Which of the following categories best describes the function of the rough endoplasmic reticulum? (eText Concept 6.4) * energy processing * information storage * breakdown of complex foods * manufacturing * structural support of cells

manufacturing

Which of the following structures is found in eukaryotic but not prokaryotic cells? (eText Concept 6.2) * ribosomes * plasma membrane * DNA * mitochondria * cytosol

mitochondria

Dye injected into a plant cell might be able to enter an adjacent cell through _____. (eText Concept 6.7) * a microtubule * plasmodesmata * a tight junction * a gap junction * a cell wall

plasmodesmata No. Although microtubules are hollow, they are a component of the cytoskeleton and do not connect the cytoplasm of adjacent cells

Which of the following groups is primarily involved in synthesizing molecules needed by the cell? (eText Concept 6.4) * rough endoplasmic reticulum, lysosome, vacuole * vacuole, rough endoplasmic reticulum, smooth endoplasmic reticulum * smooth endoplasmic reticulum, ribosome, vacuole * ribosome, rough endoplasmic reticulum, smooth endoplasmic reticulum * lysosome, vacuole, ribosome

ribosome, rough endoplasmic reticulum, smooth endoplasmic reticulum Correct. Each of these structures is capable of synthesizing molecules needed by cells

Which of the following lack membranes as part of their structure? (eText Concept 6.5) * peroxisomes * mitochondria * ribosomes * ribosomes and mitochondria * mitochondria and peroxisomes

ribosomes

Which of the following organelles might be found inside other organelles? (eText Concept 6.5) * ribosomes * the nucleolus * transport vesicles * mitochondria * No organelles are found inside of other organelles.

ribosomes

Which of the following features do prokaryotes and eukaryotes have in common? (eText Concept 6.2) * mitochondria, ribosomes, cytoplasm * mitochondria, cytoplasm, plasma membrane * ribosomes, plasma membrane, cytoplasm * ribosomes, nucleus, plasma membrane * nucleus, plasma membrane, ribosomes

ribosomes, plasma membrane, cytoplasm Prokaryotes lack organelles.

You would expect a cell with an extensive Golgi apparatus to _____. (eText Concept 6.4) * move rapidly * absorb nutrients in the GI tract * store large quantities of ions * make a lot of ATP * secrete a lot of protein

secrete a lot of protein

Cell fractionation _____. (eText Concept 6.1) * is no longer used in modern cell biology * separates cells into their component parts * requires the use of a scanning electron microscope * uses strong acids to break apart cells * None of the listed responses is correct.

separates cells into their component parts Correct. The organelles are usually separated by centrifugation.

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(s) would you predict the majority of the radioactive phosphorous to accumulate? (eText Concept 6.4) * the nucleus * the Golgi apparatus and the nucleus * the Golgi apparatus * rough endoplasmic reticulum and Golgi apparatus

the nucleus Correct. Large numbers of nucleotides would be used to make new DNA as the cells grew, and the DNA is housed in the nucleus.

A substance moving from outside the cell into the cytoplasm must pass through _____. (eText Concept 6.2) * the nucleus * the plasma membrane * a ribosome * a microtubule * the endomembrane system

the plasma membrane