mastering biology chapter 6 q+a's

Drag the terms on the left to the appropriate blanks in the sentences on the right.

1. In eukaryotic flagella, the fibers that slide past one another due to the activity of dynein proteins are microtubules. 2. Many cell organelles, most notably the nucleus, are anchored by intermediate filaments which are assembled from a diverse class of proteins. 3. Centrosomes are sites where protein dimers assemble into microtubules. 4. The extension of pseudopodia in amoeba is due to the regulated assembly and destruction of microfilaments. 5. The only cytoskeletal fibers not associated with intracellular movement or whole cell locomotion are the intermediate filaments. 6. During muscle contractions, myosin motor proteins move across tracks of microfilaments.

True or false? Proteins produced during the "chase" phase of a pulse-chase experiment are labeled with radioactive material.

False

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? See Concept 6.7 (Page 118)

Information can be transmitted from these extracellular structures to the cytoplasm

Which organelle plays a role in intracellular digestion?

Lysosome (lyso=decomposition)

Which of the following functions is NOT associated with the cytoskeleton in eukaryotic cells? See Concept 6.6 (Page 112)

Movement of RNA molecules from the nucleus to the cytoplasm

What scientific hypotheses can be tested by a pulse-chase experiment?

Movement of molecules through a cell over time

Mitochondria are found in _____. See Concept 6.5 (Page 109)

Plant and animal cells

Comparing plant cells and animal cells

Plant cell only: Cellulose cell wall, Chloroplast, Central vacuole Animal cell only: Centriole Both: Nucleus, Plasma membrane, Mitochondrion, Cytoskeleton, Endoplasmic reticulum, Golgi apparatus

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

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.

Which one of the following statements about the endomembrane system is correct? See Concept 6.4 (Page 108)

Proteins that will be secreted from the cell are likely to be found in closed spaces bounded by membranes of the endomembrane system

What path does a protein in the secretory pathway take, starting from its site of synthesis?

Rough ER, Golgi apparatus, secretory vesicles, plasma membrane

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.

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.

Which of the following statements supports the argument that viruses are nonliving?

They do not carry out metabolic processes.

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

Can you match these prefixes, suffixes, and word roots with their definitions?

below, less than: hypo- leaf: -phyll same: sym- eat: phago- formed substance: -plasm above, greater than: hyper- small: micro-

The nucleic acid of a virus particle is enclosed in a protein coat. What is it called? See Concept 19.1 (Page 397)

capsid

The predatory bacterium Bdellovibrio bacteriophorus drills into a prey bacterium and, once inside, digests it. In an attack upon a gram-negative bacterium that has a slimy cell covering, what is the correct sequence of structures penetrated by B. bacteriophorus on its way to the prey's cytoplasm?

capsule, lipopolysaccharide membrane, peptidoglycan, phospholipid membrane

Which of the following features is not unique to either prokaryotic or eukaryotic cells?

cell wall extra:Prokaryotic cells and some eukaryotic cells (plants, fungi, and some protists) have a cell wall; hence this feature cannot be used to determine whether a cell is prokaryotic or eukaryotic. Each of the other features listed is unique to either prokaryotic cells (nucleoid) or eukaryotic cells (nucleus and mitochondrion).

Can you match these prefixes, suffixes, and word roots with their definitions?

color: chrom- across: trans- body: -some (or soma-) water: aqu- (or aqua-) little, small: -elle two: bi- between: inter-

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

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 structure is common to plant and animal cells?

mitochondrion

Comparing eukaryotic and prokaryotic cells

prokaryotic only: nucleoid eukaryotic only: nucleolus, lysosome, mitochondria both: plasma membrane, ribosomes, flagelia

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

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.

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 lysosomes

Can you match these prefixes, suffixes, and word roots with their definitions?

thread: mito- true, good: eu- cell: -cyte (or cyto-) without, lack of, not: a- (or an-) green: chloro- inside, inner: endo- out of: ex-

Which of these cell junctions form a barrier to the passage of materials?

tight junctions

Cells require which of the following to form cilia or flagella?

tubulin

Which statements are true for chloroplasts? Select the three that apply.

-They are the sites of reactions that convert solar energy into chemical energy. -They contain the green pigment chlorophyll. -They have membranous sacs called thylakoids that are surrounded by a fluid called stroma.

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? See Concept 6.4 (Page 107)

Digestion of the food particle occurs in a vesicle enclosed by a membrane that separates the digestion from the cytoplasm.

_____ aid in the coordination of the activities of adjacent animal cells.

Gap (communicating) junctions

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

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.

Cilia and flagella bend because of ________.

a motor protein called dynein

To understand how cells function as the fundamental unit of life, you must first become familiar with the individual roles of the cellular structures and organelles. Drag the labels on the left onto the diagram of the animal cell to correctly identify the function performed by each cellular structure.

a-synthesizes lipids b-assembles ribosomes c-defines cell shape d-produces secretory proteins e-modifies and sorts proteins f-digests proteins g-generates ATP

Which of the following correctly matches an organelle with its function? See Concept 6.2 (Page 99)

central vacuole...storage

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?

cytoskeletal structures

The primary role of _____ is to bind animal cells together.

desmosomes

Drag the labels to their appropriate locations in the table below. Pink labels may be used more than once.

desmosomes-animal gap junctions-animal tight junctions-animal plasmodesmata-plant cellulose-plant collagen-animal

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

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

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

Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane?

mRNA

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 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

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

Which organelle often takes up much of the volume of a plant cell?

vacuole