BIO 190 CH 4

exclusively DNA

deoxyribose, thymine

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

e

prokaryotic and eukaryotic

flagella, ribosomes, plasma membrane

Many cell organelles, most notably the nucleus, are anchored by----------- which are assembled from a diverse class of proteins.

intermediate filaments

The only cytoskeletal fibers not associated with intracellular movement or whole cell locomotion are the

intermediate filaments

Tertiary structure

is achieved when a protein folds into a compact, three-dimensional shape stabilized by interactions between side-chain R groups of amino acids.

Quaternary structure

is the result of two or more protein subunits assembling to form a larger, biologically active protein complex.

Primary structure

is the sequence of amino acids in a protein.

smooth ER

lipid synthesis, poison detoxification, calcium ion storage

lysosomes

macromolecule digestion, autophagy

During muscle contractions, myosin motor proteins move across tracks of

microfilaments

The extension of pseudopodia in amoeba is due to the regulated assembly and destruction of

microfilaments

Centrosomes are sites where protein dimers assemble into

microtubules

In eukaryotic flagella, the fibers that slide past one another due to the activity of dynein proteins are

microtubules

prokaryotic only

nucleoid

dehydration reaction. forms what bond

peptide bond.

Both DNA and RNA

phosphate, adenine, guanine, cytosine

exclusively RNA

ribose, uracil

dehydration rxn

synthesis a polymer 2 molecules are covalently bonded to each other with loss of a water molecules

How many fatty acids are in a phospholipid?

2

Which of these is a carbonyl group?

C=O

Which of functional groups listed below behaves as an acid?

COOH

Which of these is a carboxyl group?

COOH

simple shape

If you wanted to show a generalized protein in which the focus is on the protein's function rather than its structure, you should use a

wireframe model

If you wanted to show the 3-dimensional shape of a protein by showing the amino acid side chains and their interactions, you should use a

space-filling model

If you wanted to show the 3-dimensional shape of a protein, including all of the atoms composing it, you should use a

ribbon model

If you wanted to show the 3-dimensional shape of a protein, including the backbone structure, folds, and coils, you should use a

simplified diagram

If you wanted to show the general shape of a protein, along with some important functional details such as folds and coils, you should use a

Which of the functional groups behaves as a base?

NH2

what is ab amino group

NH2

Which of these functional groups is characteristic of alcohol?

OH

Which of these is a hydroxyl group?

OH

Which of these groups plays a major role in energy transfer?

PO4

Which of these groups is characteristic of thiols?

SH

c

These molecules are _____. a) enantiomers b) cis-trans isomers (geometric isomers) c) structural isomers d) amines e) thiols

dehydration reaction.

When two amino acid monomers are positioned so that the carboxyl group of one is adjacent to the amino group of the other, they can be joined through

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? a) The nucleus b) Rough endoplasmic reticulum and Golgi apparatus c) The Golgi apparatus d) Rough endoplasmic reticulum e) The Golgi apparatus and the nucleus

a

A function of cholesterol that does not harm health is its role _____. a) as a component of animal cell membranes b) the most abundant male sex hormone c) as the primary female sex hormone d) in calcium and phosphate metabolism e) All of cholesterol's effects cause the body harm.

a

A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized __________. SHOW HINT a) in the rough endoplasmic reticulum b) in the plasma membrane c) in the ribosomes of the mitochondria d) in the smooth endoplasmic reticulum e) on free cytoplasmic ribosomes

a

Identify three possible components of a DNA nucleotide. View Available Hint(s) a) deoxyribose, phosphate group, thymine b) adenine, phosphate group, ribose c) cytosine, phosphate group, ribose d) deoxyribose, phosphate group, uracil e) cytidine, phosphate group, ribose f) guanine, phosphate group, ribose

a

In a bacterium, where are proteins synthesized? a) ribosomes b) nucleus c) peroxisome d) nucleoid region e) capsule

a

On the basis of the principle of complementary base pairing, you would expect the percentage of __________ in an individual's DNA to be equal to the percentage of __________. a) adenine; thymine b) adenine; guanine c) thymine; guanine d) thymine; cytosine e) adenine; cytosine

a

The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell. a) plasma membrane b) nucleoid region c) ribosome d) pili e) cell wall

a

To what does the term polypeptide refer? a) None of the listed responses is correct. b) A complex carbohydrate c) Carbohydrates with a hydrogen bond holding them together d) Amino acids linked by hydrolysis e) Monomers linked by glycosidic linkages

a

Which of the following correctly matches an organelle with its function? a) central vacuole ... storage b) mitochondrion ... photosynthesis c) lysosome ... movement d) nucleus ... cellular respiration e) ribosome ... manufacture of lipids

a

Which of the following organelles can be found in abundance in the pancreatic cells that secrete large amounts of digestive enzymes? SHOW HINT a) free cytoplasmic ribosomes b) transport vesicles c) rough endoplasmic reticulum d) Golgi apparatus e) All of the listed responses will increase in pancreatic cells secreting digestive enzymes

a

Which of the following statements is an accurate description of proteins? a) The primary structure of a protein is the order of amino acids in a polypeptide, as coded for in the DNA of a gene. b) The 20 amino acids found in proteins differ in the composition of their R groups, which may be either polar or charged. c) Secondary structures, which include the alpha helix or beta pleated sheet, are held together by interactions between R groups. d) Tertiary structure is the overall shape of a polypeptide, which may be stabilized by hydrophobic interactions, hydrogen bonds, ionic bonds, and peptide bonds. e) Quaternary structure is only found in proteins that have four identical polypeptide subunits.

a

Which of the following structures is found in eukaryotic but not prokaryotic cells? a) Mitochondria b) Ribosomes c) Cytosol d) DNA e) Plasma membrane

a

Which of these is rich in unsaturated fats? a) olive oil b) a fat that is solid at room temperature c) beef fat d) butter e) lard

a

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

a

Which structure is common to plant and animal cells? a) Mitochondrion b) Centriole c) Wall made of cellulose d) Central vacuole e) Chloroplast

a

Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why? SHOW HINT a) The intestinal cells are bound together by tight junctions. b) The intestinal cells are bound together by gap junctions. c) The intestinal cells are fused together into one giant cell. d) The intestinal cells are bound together by plasmodesmata. e) The intestinal cells are bound together by the extracellular matrix.

a

Which of the following proteins are synthesized by bound ribosomes? a) insulin b) actin c) DNA polymerase d) lysosomal enzyme e) ribosomal protein f) ER protein

a,d,f

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? SHOW HINT a) transmission electron microscope, because of its high resolving power b) light microscope, because the specimen is alive c) transmission electron microscope, because of its high magnifying power d) light microscope, because of its high resolving power e) scanning electron microscope, because of its ability to visualize the surface of subcellular objects

b

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? a) Transmission electron microscope because of its high magnifying power b) Light microscope because the specimen is alive c) Transmission electron microscope because of its high resolving power d) Light microscope because of its high resolving power e) Scanning electron microscope because of its ability to visualize the surface of subcellular objects

b

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell, they a) have a smaller nucleus b) have no membrane-bounded organelles c) lack chromosomes d) have no ribosomes e) lack a plasma membrane

b

Basal bodies are most closely associated with which of the following cell components? a) Central vacuole b) Cilia c) Nucleus d) Golgi apparatus e) Mitochondria

b

Cell fractionation a) uses strong acids to break apart cells b) separates cells into their component parts c) requires the use of a scanning electron microscope d) None of the listed responses is correct. e) is no longer used in modern cell biology

b

Cell fractionation __________. SHOW HINT a) requires the use of a scanning electron microscope b) separates cells into their smallest component parts c) uses strong acids to break apart cells d) is no longer used in modern cell biology e) None of the listed responses is correct.

b

Cis-trans isomers (geometric isomers) are molecules that _____. a) differ in their molecular formulas b) differ in the arrangement of their atoms about a double bond c) are isomers in which one of the molecules contains an amino group and the other contains a phosphate group d) are isomers that differ in the covalent partnerships between their atoms e) are mirror images

b

Dye injected into a plant cell might be able to enter an adjacent cell through __________. SHOW HINT a) a microtubule b) plasmodesmata c) a gap junction d) a cell wall e) a tight junction

b

Enantiomers are molecules that _____. a) contain an -OH group b) are mirror images c) are isomers that differ in the covalent partnerships between their atoms d) contain a carboxyl group d e) iffer in the arrangement of their molecules about a double bond

b

Glycogen is _____. a) the form in which plants store sugars b) a polysaccharide found in animals c) a source of saturated fat d) a transport protein that carries oxygen e) a polysaccharide found in plant cell walls

b

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? a) Prokaryotic cells are larger than eukaryotic cells. b) Eukaryotic cells possess specialized membrane-bounded organelles. c) Eukaryotic cells can synthesize proteins, but prokaryotic cells cannot. d) Eukaryotic cells lack many of the organelles found in prokaryotes. e) eukaryotic cells are much more successful than prokaryotic cells.

b

To which functional class of proteins does lysozyme belong? a) Structural protein b) Enzymatic protein c) Hormonal protein d) Storage protein e) Transport protein

b

What could happen if a mutation in a gene caused a hydrophobic amino acid in a polypeptide to be replaced by a hydrophilic amino acid? a) There would be no effect as long as the protein had quaternary structure, because primary structure does not affect that level. b) The new amino acid would not form the same interactions with hydrophobic R groups, and the protein's shape would likely be affected. c) The shape of the protein would not be affected if only one amino acid in the primary structure is changed. d) The hydrophilic amino acid could not form the proper peptide bond in its new location, so both the shape and function of the protein would be affected.

b

What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane? a) The nuclear pores are connections between the nuclear membrane and the endoplasmic reticulum that permit ribosomes to assemble on the surface of the ER. b) Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores. c) The nucleolus contains messenger RNA (mRNA), which crosses the nuclear envelope through the nuclear pores. d) Endoplasmic reticulum membrane is produced in the nucleolus and leaves the nucleus through the nuclear pores. e) The nucleolus passes through the nuclear membrane via the nuclear pores.

b

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

b

What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? a) Golgi—ER—lysosome b) ER—Golgi—vesicles that fuse with plasma membrane c) Lysosome—ER—Golgi d) Nucleus—ER—Golgi e) ER—lysosomes—vesicles that fuse with plasma membrane

b

Which characteristics best describe the side chains in the part of the protein in contact with the phospholipid tails of the membrane? a) Charged - acidic; hydrophilic b) Non-polar; hydrophobic c) Charged - basic; hydrophilic d) Polar; hydrophilic

b

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

b

Which of the following is/are most likely to be involved in the process of producing proteins for a chloroplast or mitochondrion? SHOW HINT a) rough endoplasmic reticulum b) free cytoplasmic ribosomes c) transport vesicles d) the Golgi apparatus e) smooth endoplasmic reticulum

b

Which of the following is/are possible site(s) of protein synthesis in a typical eukaryotic cell? a) Cytoplasm and rough endoplasmic reticulum b) cytoplasm, rough endoplasmic reticulum, and mitochondria c) Cytoplasm d) Mitochondria e) Rough endoplasmic reticulum

b

Which of the following organelles might be found inside other organelles? SHOW HINT a) transport vesicles b) ribosomes c) the nucleolus d) mitochondria e) No organelles are found inside of other organelles.

b

Which of these cell junctions form a barrier to the passage of materials? a) gap (communicating) junctions b) tight junctions c) keratin fibers d) desmosomes (anchoring junctions) e) plasmodesmata

b

You would expect a cell with an extensive Golgi apparatus to a) move rapidly b) secrete a lot of protein c) absorb nutrients in the GI tract d) store large quantities of ions e) make a lot of ATP

b

glucose + glucose —> _____ by _____. a) lactose + water ... hydrolysis b) maltose + water ... dehydration synthesis c) starch + water ... dehydration synthesis d) sucrose + water ... dehydration synthesis e) cellulose + water ... hydrolysis Previous Answers

b

hydrolysis

breaking down a polymer the bond between monomers is broken by adding a h2o

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? SHOW HINT a) the Golgi apparatus and the nucleus b) the Golgi apparatus c) the nucleus d) rough endoplasmic reticulum e) rough endoplasmic reticulum and Golgi apparatus

c

A researcher made an interesting observation about a protein made by the rough endoplasmic reticulum (ER) 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 a) smooth endoplasmic reticulum b) plasma membrane c) Golgi apparatus d) rough endoplasmic reticulum e) transport vesicles

c

As a researcher in a protein lab, you analyze two different proteins for their shape and the amino acids they contain. Your results show that the two proteins have exactly the same numbers and types of amino acids, but they have different shapes. What is the best explanation for these results? a) All proteins have the same numbers and types of amino acids. Differences between proteins are all based on shape. b) With only 20 amino acid types to work with, many proteins must have the same numbers and types. c) Each protein has a unique linear sequence of amino acids. d) Proteins from the same functional class (enzymatic, structural, etc.) contain exactly the same amino acids.

c

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell, they __________. a) lack a plasma membrane b) have a smaller nucleus c) have no membrane-bounded organelles d) have no ribosomes e) do not have genes

c

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 __________. SHOW HINT a) free in the cytoplasm of eukaryotes b) on the rough ER c) in bacterial cells d) The first two answers are correct. e) The first three answers are correct.

c

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? SHOW HINT a) in the cytoplasm, functioning as an enzyme in carbohydrate synthesis b) in a mitochondrion, functioning in ATP synthesis c) embedded in the plasma membrane, functioning in the transport of molecules into the cell d) in the internal space of the Golgi apparatus, being modified before the protein is excreted e) in the aqueous interior of a lysosome, functioning as a digestive enzyme

c

In addition to the fundamental structures required to be defined as a cell, which of the following cells -also have a nucleus and -chloroplasts? SHOW HINT a) a cell from a pine tree b) a bacterium c) a protistal cell and a plant cell d) a yeast (fungus) cell e) a cell from the intestinal lining of a cow

c

The primary role of _____ is to bind animal cells together. a) plasmodesmata b) the cytoskeleton c) desmosomes d) tight junctions e) gap (communicating) junctions

c

The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized __________. SHOW HINT a) in the Golgi apparatus b) externally to the plasma membrane c) in the rough endoplasmic reticulum and in the Golgi apparatus d) in the rough endoplasmic reticulum e) in the smooth endoplasmic reticulum

c

What holds phospholipids together in a bilayer formation? a) covalent bonds between polar heads b) ionic interactions between phospholipid tails c) hydrophilic and hydrophobic interactions with water d) interaction of cis-double bonds in tails with polar heads

c

What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell? a) capsule b) pili c) cell wall d) flagella e) nucleoid region

c

Where would you expect to find proteins involved with movement of structures within a cell? SHOW HINT a) plasma membrane b) ribosomes c) cytoskeleton d) transport vesicles moving from the ER to the Golgi e) muscles

c

Which of the following categories best describes the function of the rough endoplasmic reticulum? SHOW HINT a) structural support of cells b) energy processing c) manufacturing d) information storage e) breakdown of complex foods

c

Which of the following components of a tossed salad will pass through the human digestive tract and be digested the least? a) Oil (in the dressing) b) Protein (in the bacon bits) c) Cellulose (in the lettuce) d) Sugar (in the dressing) e) Starch (in the croutons)

c

Which of the following features do prokaryotes and eukaryotes have in common? SHOW HINT a) nucleus, plasma membrane, ribosomes b) mitochondria, ribosomes, cytoplasm c) ribosomes, plasma membrane, cytoplasm d) ribosomes, nucleus, plasma membrane e) mitochondria, cytoplasm, plasma membrane

c

Which of the following five membranes is most likely to have a lipid composition that is distinct from the other four? SHOW HINT a) endoplasmic reticulum b) Golgi apparatus c) mitochondrial outer membrane d) lysosome membrane e) plasma membrane

c

Which of the following statements correctly describes a common characteristic of cell walls and the cell extracellular matrix? a) Cell walls and the extracellular matrix are possessed by both plants and animals. b) Collagen is a major component of both cell walls and the extracellular matrix. c) Both are external to the plasma membrane. d) Both are synthesized in the nucleolus. e) Both are composed primarily of lipids.

c

Which of the following structures is found in animal cells but NOT plant cells? SHOW HINT a) plasma membrane b) mitochondria c) centrioles d) Golgi apparatus e) rough endoplasmic reticulum

c

Which of the following structures is found in animal cells but not plant cells? a) Golgi apparatus b) Rough endoplasmic reticulum c) Centrioles d) Plasma membrane e) Mitochondria

c

Which of the following structures is found in eukaryotic but not prokaryotic cells? SHOW HINT a) DNA b) plasma membrane c) mitochondria d) cytosol e) ribosomes

c

Which structure is not part of the endomembrane system? a) Nuclear envelope b) Plasma membrane c) Chloroplast d) Golgi apparatus e) All of the listed responses are part of the endomembrane system.

c

Which type of cell is likely to have the most mitochondria? a) Inactive yeast cells that are stored for future use b) Photosynthetic cells in the leaves of a tree c) Muscle cells in the legs of a marathon runner d) Bacterial cells that are growing on sugars e) Nondividing cells in the skin on your finger

c

_____ is the most abundant organic compound on Earth. a) Glycogen b) Glucose c) Cellulose d) Lactose e) Starch

c

What functional feature(s) does the phosphate group contribute to the structure of a phospholipid? a) place where bonds can form between adjoining phospholipids b) place to attach fatty acids c) negative charge to interact with water d) nonpolar group that avoids water e) place to attach another small charged molecule

c,e

animal cell only

centriole

plant cell only

chloroplast, cellulose cell wall, central vacuole

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 __________. SHOW HINT a) transport vesicles b) rough endoplasmic reticulum c) smooth endoplasmic reticulum d) Golgi apparatus e) plasma membrane

d

A substance moving from outside the cell into the cytoplasm must pass through __________. SHOW HINT a) a ribosome b) the endomembrane system c) a microtubule d) the plasma membrane e) the nucleus

d

Basal bodies are most closely associated with which of the following cell components? SHOW HINT a) nucleus b) Golgi apparatus c) mitochondria d) cilia e) the central vacuole

d

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 __________. SHOW HINT a) have a very high metabolic rate b) be a prokaryotic cell c) be nearly spherical in shape d) be involved in the rapid uptake of compounds from the cell's environment e) be buried deep in the interior of an organism

d

Dye injected into a plant cell might be able to enter an adjacent cell through a) a cell wall b) a gap junction c) a tight junction d) plasmodesmata e) a microtubule.

d

L-dopa is used to treat _____. a) muscle sprains b) Marfan's syndrome c) Alzheimer's disease d) Parkinson's disease e) laryngitis

d

What is the function of a bacterium's capsule? a) propulsion b) protein synthesis c) adhesion d) protection e) DNA storage

d

What kind of effect does R-dopa have on Parkinson's disease? a) At first it makes the symptoms worse but over the long term it alleviates the symptoms. b) It alleviates the symptoms. c) At first it alleviates the symptoms but over the long term it makes the symptoms worse. d) None. e) It makes the symptoms of Parkinson's disease worse.

d

Where is a bacterial cell's DNA found? a) ribosomes b) nucleus c) peroxisome d) nucleoid region e) capsule

d

Which molecule is less soluble in water--a fat or a phospholipid? Why? a) A fat molecule is less soluble in water because it has more carbons and hydrogens than a phospholipid. b) A phospholipid is less soluble in water because even though it has one end that is hydrophilic, the end that is hydrophobic is larger. c) A phospholipid is less soluble in water because it is smaller than a fat molecule. d) A fat molecule is less soluble in water because it has three non-polar fatty acids and no polar or charged head like a phospholipid has.

d

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

d

Which of the following features do prokaryotes and eukaryotes have in common? a) Mitochondria, cytoplasm, and plasma membrane b) Nucleus, plasma membrane, and ribosomes c) Mitochondria, ribosomes, and cytoplasm d) Ribosomes, plasma membrane, and cytoplasm e) Ribosomes, nucleus, and plasma membrane

d

Which of the following groups is primarily involved in synthesizing molecules needed by the cell? SHOW HINT a) smooth endoplasmic reticulum, ribosomes, and vacuole b) lysosomes, vacuoles, and ribosomes c) vacuole, rough endoplasmic reticulum, and smooth endoplasmic reticulum d) ribosomes, rough endoplasmic reticulum, and smooth endoplasmic reticulum e) rough endoplasmic reticulum, lysosomes, and vacuole

d

Which of the following hydrocarbons has a double bond in its carbon skeleton? a) C2H6 b) C2H2 c) CH4 d) C2H4 e) C3H8

d

Which of the following is the simplest collection of matter that can live? SHOW HINT a) Organ b) molecules c) tissue d) cell e) None of the listed responses is correct.

d

Which of the following is/are likely to limit the maximum size of a cell? SHOW HINT a) the cell's surface-to-volume ratio b) the time it takes a molecule to diffuse across a cell c) the shape of the cell d) All of the choices are correct. e) None of the choices is correct.

d

Which of the following statements about chloroplasts and mitochondria is true? SHOW HINT a) Chloroplasts and mitochondria are components of the endomembrane system. b) Chloroplasts and mitochondria have three sets of membranes. c) Mitochondria, but not chloroplasts, contain a small amount of DNA. d) Chloroplasts and mitochondria synthesize some of their own proteins. e) Chloroplasts, but not mitochondria, are completely independent of the cell of which they are a part.

d

Which of the following statements correctly describes a common characteristic of a plant cell wall and an animal cell extracellular matrix? SHOW HINT a) Both are permeable to water and small solutes. b) Both are synthesized in the ER and Golgi apparatus. c) Both are composed primarily of carbohydrates. d) The first two answers are correct. e) The first three answers are correct.

d

Which of these is a polysaccharide? a) galactose b) lactose c) glucose d) cellulose e) sucrose

d

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

d

Which structure is not part of the endomembrane system? a) Nuclear envelope b)Golgi apparatus c) Plasma membrane d) Chloroplast e) All of the listed responses are part of the endomembrane system.

d

_____ aid in the coordination of the activities of adjacent animal cells. a) Keratin fibers b) Plasmodesmata c) Desmosomes d) Gap (communicating) junctions e) Tight junctions

d

Secondary structure

describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between backbone atoms located near each other in the polypeptide chain.

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell they __________. SHOW HINT a) have no ribosomes b) lack chromosomes c) lack a plasma membrane d) have a smaller nucleus e) lack membrane-bounded organelles in their cytoplasm

e

Cilia and flagella move due to the interaction of the cytoskeleton with which of the following? a) Pseudopodia b) Mitochondria c) Actin d) Tubulin e) Motor proteins

e

Cilia and flagella move due to the interaction of the cytoskeleton with which of the following? SHOW HINT a) tubulin b) actin c) pseudopodia d) mitochondria e) motor proteins

e

Dye injected into a plant cell might be able to enter an adjacent cell through __________. a) a microtubule b) a gap junction c) a tight junction d) a cell wall e) plasmodesmata

e

Generally, animals cannot digest (hydrolyze) the glycosidic linkages between the glucose molecules in cellulose. How then do cows get enough nutrients from eating grass? a) The flat teeth and strong stomach of herbivores break the cellulose fibers so that the cows get enough nutrition from the cell contents. b) They have to eat a lot of it. c) Cows and other herbivores are exceptions and make some cellulose-digesting enzymes. d) All of the listed responses are correct. e) Microorganisms in their digestive tracts hydrolyze the cellulose to individual glucose units.

e

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? SHOW HINT a) Eukaryotic cells can synthesize proteins but prokaryotic cells cannot. b) Eukaryotic cells are larger than prokaryotic cells. c) Eukaryotic cells are much more successful than prokaryotic cells. d) Eukaryotic cells lack many of the organelles found in prokaryotes. e) Eukaryotic cells are compartmentalized, which allows for specialization.

e

Microtubules and microfilaments commonly work with which of the following to perform many of their functions? SHOW HINT a) lysosomes b) ribosomes c) Golgi apparatus d) RNA e) None of the listed responses is correct.

e

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 __________. SHOW HINT a) are produced by the nucleus of the cell b) contain two or more membranes c) are involved in energy metabolism of the cell d) are part of the endomembrane system e) must divide each time the cell containing them divides

e

Which of the following carbohydrate molecules has the lowest molecular weight? a) chitin b) lactose c) cellulose d) sucrose e) glucose

e

Which of the following categories best describes the function of the rough endoplasmic reticulum? a) Structural support of cells b) Breakdown of macromolecules c) Information storage d) Energy processing e) Manufacturing

e

Which of the following is FALSE? SHOW HINT a) Mitochondria have more than one membrane. b) The mitochondria possess their own DNA. c) The folds of the inner mitochondrial membrane are called cristae. d) Mitochondria are involved in energy metabolism. e) Mitochondria contain ribosomes in the intermembrane space.

e

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

e

Which of the following is/are possible site(s) of protein synthesis in a typical eukaryotic cell? SHOW HINT a) the cytoplasm b) the rough endoplasmic reticulum c) in mitochondria d) The first two answers are correct. e) The first three answers are correct.

e

Which of these is NOT a lipid? a) phospholipid b) wax c) steroids d) cholesterol e) RNA

e

Which of these is a source of lactose? a) starch b) potatoes c) sugar beets d) sugar cane e) milk

e

Which type of cell is most likely to have the most mitochondria? SHOW HINT a) bacterial cells that are growing on sugars b) photosynthetic cells in the leaves of a tree c) nondividing cells in the skin on your finger d) inactive yeast cells that are stored for future use e) muscle cells in the legs of a marathon runner

e

You would expect a cell with an extensive Golgi apparatus to ___________. SHOW HINT a) absorb nutrients in the GI tract b) make a lot of ATP c) store large quantities of ions d) move rapidly e) secrete a lot of protein

e

Your intestine is lined with individual cells that absorb nutrients. No fluids leak between these cells from the interior of the intestine. Why? a) The intestinal cells are bound together by gap junctions. b) The intestinal cells are fused together into one large cell. c) The intestinal cells are bound together by plasmodesmata. d) The intestinal cells are bound together by the extracellular matrix. e) The intestinal cells are bound together by tight junctions.

e

_____ are surface appendages that allow a bacterium to stick to a surface. a) Flagella b) Cell walls c) Ribosomes d) Mitochondria e) Fimbriae

e

plant and animal cell

endoplasmic reticulum, Golgi apparatus, mitochondrion, nucleus, plasma membrane, cytoskeleton

protein synthesis order

endoplasmic reticulum--> cis golgi-->medial golgi--> trans golgi cisternae--> plasma membrane--> extracellular space

eukaryotic only

mitochondria, nucleolus, lysosome

Golgi apparatus

protein modification and sorting, cisternal maturation

rough ER

protein synthesis