Week 4-5

Question 1

Which of these is the simplest unit of life?

a) organ
b) molecules
c) cell
d) tissue

Answer 1

c) cell

Question 2

Which feature do prokaryotes and eukaryotes have in common?

a) ribosomes, plasma membrane, cytoplasm
b) ribosomes, nucleus, plasma membrane
c) mitochondria, ribosomes, cytoplasm
d) mitochondria, cytoplasm, plasma membrane
e) nucleus, plasma membrane, ribosomes

Answer 2

a) ribosomes, plasma membrane, cytoplasm

Question 3

In addition to the fundamental structures required to be defined as a cell, which cell type(s) also has/have a nucleus and chloroplasts?

a) a bacterium
b) a cell from a pine tree
c) a protist cell and a plant cell
d) a yeast (fungus) cell
e) a cell from the intestinal lining of a cow

Answer 3

c) a protist cell and a plant cell

Question 4

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?

a) rough ER
b) smooth ER
c)Golgi apparatus
d) nuclear envelope
e) lysosomes

Answer 4

b) smooth ER

Question 5

What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane?

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

Answer 5

d) Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores.

Question 6

Which of the following correctly describes the pathway taken by a protein destined for secretion from an animal cell?

a) plasma membrane → transport vesicle → Golgi → transport vesicle → rough ER
b) Golgi → rough ER → transport vesicle → plasma membrane
c) rough ER → transport vesicle → lysosome → transport vesicle → plasma membrane
d) rough ER → transport vesicle → Golgi → transport vesicle → plasma membrane
e) rough ER → transport vesicle → Golgi → transport vesicle → lysosome → plasma membrane

Answer 6

d) rough ER → transport vesicle → Golgi → transport vesicle → plasma membrane

Question 7

Which category best fits the function of the rough endoplasmic reticulum?

a) energy processing
b) manufacturing
c) breakdown of complex foods
d) information storage
e) structural support of cell

Answer 7

b) manufacturing

Question 8

Which of the following statements about the cytoskeleton is correct?
a) Transport vesicles move between organelles of the endomembrane system independently from the cytoskeleton.
b) Microfilaments are structurally rigid and resist compression, whereas microtubules resist tension (stretching).
c) Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other.
d) Chemicals that block the assembly of the cytoskeleton would cause little effect on the cell’s response to external signals and stimuli.
e) None of the listed scenarios apply here

Answer 8

c) Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other.

Question 9

Consider a protein that is made in the rough endoplasmic reticulum. When the synthesis of the protein is complete, the protein is located in the ER membrane. Where else in the cell might this protein be found?

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

Answer 9

c) embedded in the plasma membrane, functioning in the transport of molecules into the cell

Question 10

A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized __________.

a) on free cytoplasmic ribosomes
b) in the ribosomes of the mitochondria
c) in the plasma membrane
d) in the smooth endoplasmic reticulum
e) in the rough endoplasmic reticulum

Answer 10

e) in the rough endoplasmic reticulum

Question 11

Chloroplasts and mitochondria are thought to have started as prokaryotes. One piece of support for this hypothesis is these organelles’ prokaryotic-type ribosomes. These ribosomes are probably most similar to ribosomes found __________.

a) free in the cytoplasm of eukaryotes
b) on the rough ER
c) in bacterial cells
d) free in the cytoplasm of eukaryotes and on the rough ER
e) None of the listed responses are correct.

Answer 11

c) in bacterial cells

Question 12

Which type of cell will have the most mitochondria?

a) nondividing cells in the skin on your finger
b) muscle cells in the legs of a marathon runner
c) inactive yeast cells that are stored for future use
d) bacterial cells that are growing on sugars
e) photosynthetic cells in the leaves of a tree

Answer 12

b) muscle cells in the legs of a marathon runner

Question 13

The person credited with first recognizing (in the 1850s) that living cells cannot arise spontaneously, but arise only from previously existing cells, is __________.

a) Anton van Leeuwenhoek
b) Watson
c) Robert Hooke
d) Rudolf Virchow
e) Louis Pasteur

Answer 13

d) Rudolf Virchow

Question 14

Microtubules and microfilaments commonly work with what to perform many of their functions?

a) lysosomes
b) ribosomes
c )Golgi apparatus
d) RNA
e) None of the listed responses is correct.

Answer 14

e) None of the listed responses is correct.

Question 15

Which structure is found in animal cells but not in plant cells?

a) centrioles
b) plasma membrane
c) rough endoplasmic reticulum
d) Golgi apparatus
e) mitochondria

Answer 15

a) centrioles

Question 16

Where would you expect to find proteins involved with movement of structures within a cell?

a) muscles
b) transport vesicles
moving from the ER to the Golgi
c) plasma membrane
d) cytoskeleton
e) ribosomes

Answer 16

d) cytoskeleton

Question 17

Basal bodies are most closely associated with which of the following cell components?

a) cilia
b) the central vacuole
c) Golgi apparatus
d) mitochondria
e) nucleus

Answer 17

a) cilia

Question 18

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 __________.

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

Answer 18

d) be involved in the rapid uptake of compounds from the cell’s environment

Question 19

Which statement correctly describes characteristic shared by plant cell walls and an animal cell extracellular matrices?

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 are correct

Answer 19

d) The first two answers are correct.

Question 20

The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized __________.

a) in the smooth endoplasmic reticulum
b) in the rough endoplasmic reticulum and in the Golgi apparatus
c) externally to the plasma membrane
d) in the Golgi apparatus
e) in the rough endoplasmic reticulum

Answer 20

b) in the rough endoplasmic reticulum and in the Golgi apparatus

Question 21

Which statement about the fluid mosaic model is true?

a) Only phospholipids are capable of moving in the membrane.
b) The mosaic aspect of the membrane is due to the glycosylation of inner leaflet phospholipids.
c) The fluid aspect of the membrane is due to the lateral and rotational movement of phospholipids, and embedded proteins account for the mosaic aspect.
d) The fluid aspect of the membrane is due to the behavior of phospholipids, and the mosaic aspect is due to the presence of carbohydrates.
e) The fluid aspect of the membrane describes its structure at normal temperatures, and the mosaic aspect describes the behavior of the membrane as the temperature is lowered.

Answer 21

c) The fluid aspect of the membrane is due to the lateral and rotational movement of phospholipids, and embedded proteins account for the mosaic aspect.

Question 22

Which functional process is not a consequence of the association of proteins with biological membranes?

a) cell-cell communication
b) intercellular joining
c) cell-cell recognition
d) enzymatic activity
e) energy, carbon, and nitrogen storage

Answer 22

e) energy, carbon, and nitrogen storage

Question 23

Which process does not occur in dividing bacteria?

a) binary fission
b) inward growth of the plasma membrane
c) replication of DNA
d) separation of the origins of replication
e) mitosis

Answer 23

e) mitosis

Question 24

Which is involved in the binary fission of bacteria?

a) distribution of a copy of the single parental chromosome to each daughter cell
b) formation of a cell plate
c) disintegration of the nuclear membrane
d) prophase, prometaphase, metaphase, anaphase, and telophase
e) formation of a spindle apparatus

Answer 24

a) distribution of a copy of the single parental chromosome to each daughter cell

Question 25

Which statement is correct concerning carbohydrates associated with the plasma membrane? a) The carbohydrate composition of most eukaryotic plasma membranes is quite similar. b) Membrane carbohydrates function primarily in cell-cell recognition. c) Carbohydrates associated with the plasma membrane are located on both surfaces of the membrane. d) Carbohydrates are only found associated with the membranes of prokaryotic cells. e) Carbohydrates on the plasma membrane are typically short chains of between two and five monosaccharides.

Answer 25

b) Membrane carbohydrates function primarily in cell-cell recognition.

Question 26

Where in the fluid mosaic model of the membrane would carbohydrates be found? a) on the inside (cytoplasmic) surface of the membrane b) on the outside (external) surface of the membrane c) on both hydrophilic surfaces of the membrane, but not in the hydrophobic interior d) Carbohydrates are rarely associated with plasma membranes. e) in the interior of the membrane

Answer 26

b) on the outside (external) surface of the membrane

Question 27

The tail of a phospholipid is _________. a) Made of carbohydrates b) Made of proteins c) Made of nucleic acids d) Hydrophobic e) None of the listed responses are correct

Answer 27

d) Hydrophobic

Question 28

Which molecule is most likely to passively diffuse across the plasma membrane? a) DNA b) hemoglobin c) glucose d) sodium ion e) carbon dioxide

Answer 28

e) carbon dioxide

Question 29

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

Answer 29

a) the plasma membrane

Question 30

A single-celled organism isolated from a deep-sea hot thermal vent was found to have a cell wall but lacked a nucleus. This organism is most likely a member of which of the following domains? a) Eukarya b )Archaea c) Animalia d) Plantae e) Fungi

Answer 30

b )Archaea

Question 31

The head of a phospholipid is __________. a) Made of carbohydrates b) Made of proteins c) Made of nucleic acids d) Hydrophobic e) None of the listed responses are correct

Answer 31

e) None of the listed responses are correct

Question 32

What is the function of proteins in cell membranes? a) Cellular transport b) Photosynthesis c) Cellular respiration d) Translation

Answer 32

a) Cellular transport

Question 33

What is the function of the carbohydrates in the cell membrane? a) Pumps and channels b) Communication c) Strength d) Break down organelles e) All of the listed responses are correct.

Answer 33

b) Communication

Question 34

Which of these statements best describes the function of the cell membrane? a) It allows substances to freely enter and exit the cell. b) It controls which substances enter and exit the cell. c) It prevents substances from entering the cell d) It prevents substances from leaving the cell. e) None of the listed responses are correct.

Answer 34

b) It controls which substances enter and exit the cell.

Question 35

Where are peripheral proteins attached? a) The surface of the cell membrane via covalent bonds b) The rough endoplasmic reticulum c) The Golgi apparatus d) The interior of the cell membrane e) All of the listed responses are correct

Answer 35

d) The interior of the cell membrane

Question 36

If you were studying typical bacteria, what would be most useful for visualizing them? A. unaided eye B. light microscope C. electron microscope D. A and B E. B and C

Answer 36

E. B and C

Question 37

Which cellular structure is common to all three domains of life? A. nucleus B. endoplasmic reticulum C. mitochondria D. ribosomes E. endocytotic vesicles

Answer 37

D. ribosomes

Question 38

Which would be the most surprising to find as part of a prokaryotic cell? A. nucleoid B. chloroplast C. ribosome D. plasma membrane E. cell wall

Answer 38

B. chloroplast

Question 39

Cells, such as bacteria, are taken up by other cells, such as immune cells, by which process? A. pinocytosis B. exocytosis C. receptor-mediated endocytosis D. phagocytosis E. facilitated diffusion

Answer 39

D. phagocytosis Phagocytosis is the cellular "eating"

Question 40

Enzymes responsible for biosynthesis of membrane lipids would be located in what part of the cell shown? A. endoplasmic reticulum B. nucleus C. lysosomes D. Golgi E. plasma membrane

Answer 40

A. endoplasmic reticulum

Question 41

Autophagy removes old, damaged organelles like mitochondria. Which organelle is most critical for autophagy? A. smooth E R B. peroxisomes C. rough E R D. lysosomes E. Golgi apparatus

Answer 41

D. lysosomes Lysomes perform the digestion that is part of autography

Question 41

What is the correct order for secretion (e.g., a protein such as insulin)? A. rough E R, endosome, Golgi, smooth E R B. rough E R, Golgi, smooth E R, exocytosis C. smooth E R, rough E R, exocytosis, Golgi D. rough E R, Golgi, transport vesicle, exocytosis E. rough E R, Golgi, endosome, exocytosis, transport vesicle

Answer 41

D. rough E R, Golgi, transport vesicle, exocytosis

Question 42

If you applied a drug to block mitochondrial function, what would an affected cell lack most? A. protein B. A T P C. enzymes D. vesicles E. membranes

Answer 42

B. ATP The mitochondrion is the powerhouse of the cell

Question 43

Which best describes the structure of a biological membrane? A. two layers of phospholipids with proteins embedded between the two layers B. a mixture of covalently linked phospholipids and proteins that determines which solutes can cross the membrane and which cannot C. two layers of phospholipids with proteins either crossing the layers or on the surface of the layers D. a fluid structure in which phospholipids and proteins move freely between sides of the membrane E. two layers of phospholipids (with opposite orientations of the phospholipids in each layer) with each layer covered on the outside with proteins

Answer 43

C. two layers of phospholipids with proteins either crossing the layers or on the surface of the layers

Question 44

A drug that blocks muscular contraction might have disrupted what? a) microfilaments b) intermediate c) filaments d) ribosomes e)plasmodesmata

Answer 44

a) microfilaments

Question 45

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

Answer 45

b) None of the listed organelles are part of the endomembrane system.

Question 46

Which cell structure allows selective permeability between a cell and its external environment? a) endoplasmic reticulum b) the plasma membrane c) chloroplasts d) lysosomes e) mitochondria

Answer 46

b) the plasma membrane

Question 47

If a treatment were available that would disrupt the nuclear lamina in living cells, what would you expect to be the most likely immediate consequence for the cell? a) closure of nuclear pores disrupting transport of materials into and out of the nucleus b) the loss of chromosome function c) All of the listed choices are correct d) a change in the shape of the nucleus e)the inability of the nucleus to divide during cell division

Answer 47

c) All of the listed choices are correct

Question 47

A mutation that inactivates an enzyme involved in the modification of sugars associated with glycoproteins is most likely to affect the function of which of the following cellular structures? a) smooth endoplasmic reticulum b) None of the listed scenarios apply here c) transport vesicles produced by the rough endoplasmic retitulum d) cisternae of the Golgi apparatus e) transport vesicles produced by the trans face of the Golgi apparatus

Answer 47

d) cisternae of the Golgi apparatus

Question 48

Cilia and flagella move due to the interaction of the cytoskeleton with what? a) motor proteins b) mitochondria c) pseudopodia d) actin e) tubular

Answer 48

a) motor proteins

Question 49

A researcher wants to film the movement of chromosomes during cell division. Which type of microscope should be chosen and why? 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) scanning electron microscope, because of its ability to visualize the surface of subcellular objects e) light microscope, because of its high resolving power

Answer 49

b) light microscope, because the specimen is alive

Question 50

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? a) Eukaryotic cells can synthesize proteins but prokaryotic cells cannot. b) Eukaryotic cells are compartmentalized, which allows for specialization. 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 larger than prokaryotic cells.

Answer 50

b) Eukaryotic cells are compartmentalized, which allows for specialization.

Question 50

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

Answer 50

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

Question 51

Which type of biological macromolecule is the main component of the plasma membrane? a) carbohydrate b) lipid c) None of the listed choices is correct. d) nucleic acid e) protein

Answer 51

b) lipid

Question 52

Which statement about the role of phospholipids in the structure and function of biological membranes is correct? a) Phospholipids are completely insoluble in water. b) Phospholipids form a selectively permeable structure. c) Phospholipids form a structure in which the hydrophobic portion faces outward. d) Phospholipids form a single sheet in water. e) They are triacylglycerols, which are commonly available in foods

Answer 52

b) Phospholipids form a selectively permeable structure.

Question 53

During binary fission in a bacterium __________. a) the two DNA molecules attach to the centrioles b) bacterial circular DNA is replicated but bacterial plasmids are not c) bacterial circular DNA as well as bacterial plasmids are replicated d) the two DNA molecules break up into plasmids e) the two DNA molecules float free in the cell and are guided to daughter cells by a spindle-like apparatus

Answer 53

c) bacterial circular DNA as well as bacterial plasmids are replicated

Question 54

Under the fluid mosaic model, where in the plasma membrane would cholesterol most likely be found? a) in the interior and on the inside surface, but not on the outside surface b) on either surface of the membrane, but not in the interior of the membrane c) on the inside (cytoplasmic) surface d) on the outside (external) surface of the membrane e) wedged between phospholipid molecules in the interior of the membrane

Answer 54

e) wedged between phospholipid molecules in the interior of the membrane

Question 54

Proteins are not embedded in the cell membrane. False True

Answer 54

FALSE

Question 55

When a potassium ion (K+) moves from the soil into the vacuole of a root cell , it must pass through several cellular structures. Which of the following correctly describes the order in which these structures will be encountered by the ion? a) cell wall → plasma membrane → cytoplasm → vacuole b) plasma membrane → cell wall → cytoplasm → vacuole c) cell wall → plasma membrane → vacuole → cytoplasm d) plasma membrane → cell wall → lysosome → cytoplasm → vacuole e) None of the listed scenarios apply here

Answer 55

a) cell wall → plasma membrane → cytoplasm → vacuole

Question 56

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

Answer 56

a) a plasmodesma

Question 57

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell they __________. a) have no ribosomes b) lack chromosomes c) cannot replicate their DNA d) lack a plasma membrane e) lack membrane-bounded organelles in their cytoplasm

Answer 57

e) lack membrane-bounded organelles in their cytoplasm

Question 57

You would know a dividing cell was a plant cell rather than an animal cell if you saw that __________. a) it had formed a cell plate b) it had two pairs of centrioles during prophase c) the nucleolus was visible during metaphase d) it had microtubules e) it had formed a cleavage furrow

Answer 57

a) it had formed a cell plate

Question 58

Which is involved in the binary fission of bacteria? a) formation of a cell plate b) formation of a spindle apparatus c) disintegration of the nuclear membrane d) prophase, prometaphase, metaphase, anaphase, and telophase e) distribution of a copy of the single parental chromosome to each daughter cell

Answer 58

e) distribution of a copy of the single parental chromosome to each daughter cell

Question 59

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

Answer 59

e) free cytoplasmic ribosomes

Question 60

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

Answer 60

a) secrete a lot of protein

Question 61

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

Answer 61

d) The intestinal cells are bound together by tight junctions.

Question 62

Which molecule will diffuse most quickly across a lipid bilayer? a) glucose b) protein molecule c) H2O b) O2 (oxoigen) c) Na+ (sodium ions)

Answer 62

b) O2 (oxoigen)

Question 63

All statements describe major functions of membrane proteins, EXCEPT: a) Attachment to the cytoskeleton and extracellular matrix b) Cell-cell recognition c) Protein synthesis d) Cellular transport

Answer 63

c) Protein synthesis

Question 63

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

Answer 63

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

Question 64

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

Answer 64

c) diffusion time, surface area-to-volume ratio, and shape

Question 65

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

Answer 65

c) Golgi apparatus

Question 66

A researcher disrupts cells and separates subcellular components using centrifugation. What is the primary factor that determines whether a specific cellular component remains in the liquid solution or ends up in the pellet? a) how hydrophobic the component is b) the relative solubility of the component c) the relative size and weight of the component d) None of the listed scenarios apply here e) the carbohydrate composition of the component

Answer 66

c) the relative size and weight of the component

Question 67

In the phospholipid bilayer, which ways do the nonpolar tails face? a) The directions are scattered. b) Towards the exterior c) None of the listed choices are correct. d) Towards the interior e) No tails exist in the phospholipid bilayer.

Answer 67

d) Towards the interior