Chapter.4 Full Test Bank Life Is Cellular

Chapter 04: Life Is Cellular

MULTIPLE CHOICE

1. Which of the following is a part of accepted cell theory?

a.	Every living organism is composed of one or more cells, and all living cells have membrane-enclosed organelles.
b.	All living cells arise from preexisting cells, and all living cells have membrane-enclosed organelles.
c.	All living cells have membrane-enclosed organelles.
d.	Every living organism is composed of one or more cells, and all living cells arise from preexisting cells.

2. Which of the following types of organisms are single-celled (unicellular)?

a.	bacteria, yeast, and many protozoans
b.	many fungi, some protozoans, and plants
c.	plants and animals
d.	many fungi, plants, and animals

3. Adenine (A), thymine (T), guanine (G), and cytosine (C) are the ________ building blocks for DNA; they are organized in different combinations to code for all of the proteins needed to accomplish everything the cell does.

a.	carbohydrate	c.	protein
b.	nucleotide	d.	lipid

4. Which of the following accurately describes viruses?

a.	They are small, cellular infectious agents that are only capable of reproducing when inside a living cell, and they can attack plants as well as animals.
b.	Each is typically a piece of genetic material encased in proteins, and they can reproduce on their own.
c.	They can attack plants, animals, and protozoans, and each is typically a piece of self-replicating genetic material encased in proteins.
d.	Typically a piece of genetic material encased in proteins, viruses are small, noncellular infectious agents that are only capable of reproducing when inside a living cell such as those of plants, animals, fungi, protozoans, or bacteria.

5. Some antibiotics used to treat bacterial infections kill the bacteria by chemically punching holes in the cell wall of the bacteria, by preventing the bacteria from replicating their DNA, or by many other actions that ultimately cause cell death. Why do these antibiotics not work to kill viruses and cure people of viral infections?

a.	Antibiotics cannot kill a virus because viruses are not living cells with cell walls to puncture, nor do they have their own organelles to replicate DNA.
b.	Viruses are too virulent to be killed by those antibiotics.
c.	Viruses are too quick for the antibiotics to work.
d.	Viruses mutate at a rate faster than the rate at which antibiotics can kill them.

6. Scientists repeat their experiments over and over again because they

a.	never get it right the first time.
b.	can never be sure what procedural steps they followed the first few times.
c.	must make sure the results were not accidents and that they are repeatable.
d.	simply have extra time and resources that must be used.

7. Living cells have an intact phospholipid bilayer that separates the cell from its external environment; this structure is commonly referred to as the

a.	nucleus.	c.	endoplasmic reticulum.
b.	mitochondria.	d.	plasma membrane.

8. Liposomes form spontaneously from ________ and are important because ________.

a.	DNA; they provide a rigid structure to support the cell
b.	phospholipid monolayers; these phospholipid monolayers provide a stable barrier between the internal and external environments
c.	rigid cell walls; they provide support for the living cell and a barrier between the external and internal environments
d.	phospholipid bilayers; they provide a barrier between an external environment and an internal environment

9. An experiment mixed oil (lipids), organophosphate-containing detergent in water, and copper ions to act as a catalyst for a chemical reaction. Membranes budded off of the oil in this mixture. Which of the following is a reasonable and possible explanation of the experimental results?

a.	The chemical reaction caused the organophosphates from the detergent to chemically combine with lipids from the oil to form phospholipids. The hydrophilic tails lined up toward each other with their hydrophobic heads pointing out toward the water; this configuration formed a phospholipid bilayer that pulled into a liposome.
b.	The chemical reaction caused the organophosphates from the detergent to chemically combine with lipids from the oil to form phospholipids with hydrophilic heads and hydrophobic tails. The hydrophobic tails lined up toward each other with their hydrophilic heads pointing out toward the water; this configuration formed a phospholipid bilayer that pulled into a spherical liposome.
c.	The copper ions permanently, chemically combined with the lipids to form phospholipids. The hydrophilic tails lined up toward each other with their hydrophobic heads pointing out toward the water; this configuration formed a phospholipid bilayer that pulled into a liposome.
d.	The copper ions permanently, chemically combined with the lipids and phosphates to form phospholipids. The hydrophilic tails lined up toward each other with their hydrophobic heads pointing out toward the water; this configuration formed a phospholipid bilayer that pulled into a liposome.

10. Phospholipids are large organic molecules with a hydrophilic, polar phosphate head connected to hydrophobic, nonpolar fatty acid tails. These molecules arrange themselves to form a mostly impermeable barrier between a liposome and its environment by lining up

a.	hydrophilic head to hydrophilic head with the tails all facing outward from the center line of the membrane.
b.	hydrophobic tails facing each other at the center line of the membrane with the hydrophilic heads facing outward, away from the center line of the membrane.
c.	hydrophobic tails facing hydrophilic heads.
d.	hydrophilic tails facing hydrophobic heads with every other tail facing outward from the center line of the membrane.

11. Which of the following statements best describes the differences between the nuclear envelope and the plasma membrane?

a.	The nuclear envelope consists of two concentric phospholipid bilayers, while the plasma membrane is only one phospholipid bilayer. Both membranes are selectively permeable and have pores.
b.	The nuclear envelope consists of two concentric phospholipid bilayers, while the plasma membrane is only one phospholipid bilayer. Neither membrane is selectively permeable or has pores.
c.	Both membranes consist of two concentric phospholipid bilayers, are selectively permeable, and have pores.
d.	Both membranes consist of two concentric phospholipid bilayers, and neither is selectively permeable or has pores.

12. The selective permeability of a phospholipid bilayer membrane can be increased with help from ________ proteins.

a.	transport
b.	channel
c.	passive carrier
d.	transport proteins, channel proteins, and passive carrier

13. During the process of ________, water diffuses across a semipermeable membrane from an area where water is more concentrated to an area where water is less concentrated (it moves along the water concentration gradient).

a.	osmosis	c.	facilitated diffusion
b.	simple diffusion	d.	pinocytosis

14. Cells naturally, without using energy, respond to changes in water concentration through the process of

a.	facilitated diffusion.	c.	phagocytosis.
b.	osmosis.	d.	active transport.

15. The plasma membrane of some white blood cells contain ________ proteins that bind with proteins of cells such as bacteria that have invaded the human body.

a.	channel	c.	diffusion
b.	receptor	d.	carrier

16. If the concentration of sugar molecules in water on side “A” of a selectively permeable membrane is

5 percent, and the concentration of sugar molecules in water on side “B” of a selectively permeable membrane is 15 percent, the water will

a.	mostly move from side “B” to side “A” because the water concentration is higher on side“B.”
b.	mostly move from side “A” to side “B” because the water concentration is higher on side“A.”
c.	mostly move from side “A” to side “B” because the water concentration is higher on side“B.”
d.	not move at all because the water concentrations are isotonic.

17. A screen door allows breezes to enter and aromas to exit but keeps out insects. Its function most resembles

a.	the cytosol.	c.	the ER lumen.
b.	the plasma membrane.	d.	a ribosome.

18. Cheryl is in a lab attempting to prepare a slide of cow blood for observation in a wet mount. She places a small drop of the blood on a slide, adds a drop of strong saline (salt) solution, and then covers all of it with a coverslip. After returning to her desk, she observes the slide with her microscope and notices that all of the red blood cells (RBCs) do not look like the nice round donut-shaped cells in her lab manual. Instead, the RBCs look very shriveled up. Her lab partner, Derek, has also made a slide, but the RBCs on his slide do look like the ones in the lab manual. Derek used a more dilute solution of saline but the same vial of blood.

The most plausible explanation for the appearance of the blood cells on Cheryl’s slide is that the

a.	saline she used was hypotonic to the RBCs; this resulted in water osmosing through the RBC plasma membrane mostly into the cells.
b.	saline she used was isotonic to the RBCs; this resulted in water osmosing through the RBC plasma membrane into and out of the cells at an equal rate.
c.	saline she used was hypertonic to the RBCs; this resulted in water osmosing through the RBC plasma membrane mostly out of the cell.
d.	RBCs were hypertonic to the saline; this resulted in water osmosing through the RBC plasma membrane mostly into the cells.

19. Dialysis tubing is a selectively permeable membrane that can be filled with a solution to simulate a cell. A piece of dialysis tubing has been filled with a cloudy white solution of 5 percent starch, 5 percent egg albumin (protein), and 5 percent glucose (a small sugar) dissolved in water to simulate a cell. This simulated cell is weighed and then placed in a beaker of water. After soaking in the water for one hour, the simulated cell is once again weighed.

Over time, the weight of the simulated cell can be expected to

a.	decrease because it is hypotonic to the beaker environment and water will enter the simulated cell through osmosis.
b.	decrease because it is hypertonic to the beaker environment and water will leave the simulated cell through osmosis.
c.	increase because the solution in the beaker is hypotonic to the simulated cell and water will enter the simulated cell through osmosis.
d.	remain constant because it is isotonic to the beaker environment and water will be drawn into the simulated cell because of the albumin.

20. Examine the figure below. Assume each sugar molecule represents a percentage point of sugar dissolved in the solution. Over time, the solution level on the left side of the figure would ________, while the solution level on the right side of the figure would ________. This is because the solution on the left side of the figure is ________, while the solution on the right side of the figure is ________.

a.	rise; decrease; hypertonic; hypotonic
b.	decrease; rise; hypertonic; hypotonic
c.	decrease; rise; hypotonic; hypertonic
d.	There will be no net movement of water because the solutions are isotonic.

21. Examine the figure below. Assume each sugar molecule represents a percentage point of sugar dissolved in the solution. Over time, the solution level on the left side of the figure would ________, while the solution level on the right side of the figure would ________. This is because the solution on the left side of the figure is ________, while the solution on the right side of the figure is ________.

a.	rise; decrease; hypertonic; hypotonic
b.	decrease; rise; hypertonic; hypotonic
c.	decrease; rise; hypotonic; hypertonic
d.	There will be no net movement of water because the solutions are isotonic.

22. Which of the following statements MOST accurately describes a selectively permeable membrane?

a.	Solutes are never able to cross the membrane.
b.	Large molecules are always excluded from crossing the membrane.
c.	Substances can only pass through the membrane with the help of either active or passive transport proteins.
d.	Certain solutes move freely across the membrane by simple diffusion, while others must be helped across by active or passive transport proteins; some substances are completely excluded from crossing the membrane.

23. If a bottle of perfume was spilled in the corner of a large lecture hall, the students sitting near that corner of the room would very quickly smell the perfume. Over time, the students sitting in the far corner of the room would smell the perfume. What phenomenon has occurred to the perfume molecules that have entered the air?

a.	osmosis	c.	active transport
b.	facilitated diffusion	d.	simple diffusion

24. A scientist is observing a membrane through which water and some small hydrophobic molecules can freely pass along a concentration gradient from high to low. However, some sugar molecules are too large to pass through the membrane either way without the assistance of passive transport proteins. Additionally, small Na^ ions and some proteins can pass through the membrane against the concentration gradient, but both require the assistance of active transport proteins. What general type of membrane are they observing?

a.	impermeable	c.	semipermeable
b.	impenetrable	d.	completely permeable

25. Which of the following would be likely to require facilitated diffusion to move across the plasma membrane?

a.	water (H₂O)
b.	sodium ions (Na^), hydrogen ions (H^), sugars, and amino acids
c.	oxygen (O₂)
d.	carbon dioxide (CO₂)

26. Ross buys a bunch of small, round, red radishes at the grocery store; they are on sale because they have been sitting in the produce aisle for a while. When he gets home he notices their texture is not as crisp and crunchy as he would like. Ross’s friend recommends that he refrigerate them in a bowl of water overnight. The next day the radishes are crisp and crunchy again. The most likely explanation of why they became crunchy again after soaking in water is that the water was ________ to the radish cells it contained. So, the water osmosed across the plasma membranes ________ the radish cells, ________ the turgor pressure inside of the cells.

a.	hypertonic; into; increasing
b.	hypotonic; out of; decreasing
c.	hypertonic; into; decreasing
d.	hypotonic; into; increasing

27. Why would hydrophilic substances such as sodium ions (Na^), hydrogen ions (H^), sugars, and amino acids be unable to simply diffuse across a plasma membrane?

a.	They readily mix with the hydrophobic tails forming the core of the phospholipid bilayer.
b.	They are repelled by the hydrophilic heads of the phospholipids that form the phospholipid bilayer.
c.	They do not readily mix with the hydrophobic tails forming the core of the phospholipid bilayer; therefore, they must move across by facilitated diffusion.
d.	They do not readily mix with the hydrophobic tails forming the core of the phospholipid bilayer; therefore, the only way they can move into the cell is by endocytosis.

28. An amoeba, a protozoan that moves by pseudopodia, approaches a smaller protozoan and extends its pseudopodia (extensions of cytoplasm in plasma membrane) around the smaller protozoan. Once the amoeba’s pseudopodia completely surrounds the other protozoan, the amoeba’s plasma membrane pinches off by folding back into the amoeba and creating a vesicle containing the smaller protozoan. This vesicle is now within the amoeba itself and will soon fuse with other vesicles containing digestive enzymes. This is an example of

a.	pinocytosis.	c.	osmosis.
b.	exocytosis.	d.	phagocytosis.

29. A white blood cell (WBC) encounters bacteria in a scrape on the knee of a child who has fallen off of his bicycle. The WBC’s job is to take the bacteria inside of itself and destroy the bacteria. If the bacteria cannot be moved across the WBC membrane, how will the WBC most likely take it in?

a.	exocytosis	c.	facilitated diffusion
b.	pinocytosis	d.	phagocytosis

30. A protein molecule, transferrin, embedded in the plasma membrane recognizes iron molecules and causes the plasma membrane to fold in around the iron and take it into the cell. This is an example of

a.	osmosis.	c.	receptor-mediated endocytosis.
b.	diffusion.	d.	pinocytosis.

31. Which of the following would be likely to move through a plasma membrane by simple diffusion?

a.	water (H₂O), carbon dioxide (CO₂), and oxygen (O₂)
b.	polysaccharides, large protein molecules, and low-density lipoprotein particles
c.	bacteria and yeast
d.	sodium ions (Na^), hydrogen ions (H^), sugars, and amino acids

32. Neurotransmitters are chemicals that transmit a nerve impulse across the gap between nerve endings. These chemicals are often large and unable to pass through the membrane, so the cell packages them in a vesicle that can fuse with the plasma membrane. The inside of the vesicle opens to the outside of the cell, releasing the neurotransmitters into the gap. This type of transport of cellular products is called

a.	pinocytosis.	c.	exocytosis.
b.	receptor-mediated endocytosis.	d.	phagocytosis.

33. Cells lining blood vessels can form vesicles outside of the cell that can fold into the cell taking in liquids and solutes from the bloodstream. This is an example of

a.	pinocytosis.	c.	exocytosis.
b.	receptor-mediated endocytosis.	d.	phagocytosis.

34. A factory with an office that controls the information sent to separate rooms for each of the manufacturing and shipping processes would be analogous to a

a.	virus.
b.	prokaryotic cell with a nucleus.
c.	prokaryotic cell without a nucleus.
d.	eukaryotic cell with a nucleus.

35. The enzymes needed to perform photosynthesis in plant cells are closely associated with the membranes in

a.	chloroplasts.	c.	mitochondria.
b.	plasma membrane.	d.	ER.

36. Prokaryotes and eukaryotes are primarily distinguished by the absence or presence of internal

a.	ribosomes.
b.	membranes.
c.	membrane-enclosed organelles.
d.	cell walls.

37. The membranes of the mitochondria provide a place for enzymes needed for ________to anchor and function.

a.	photosynthesis	c.	mitosis
b.	export of proteins	d.	cellular respiration

38. Martin observes a wet mount slide preparation using the compound light microscope in the lab room. He observes layers of cells that have a definite, rigid, rectangular shape; there appears to be a nucleus in all of the cells and there are many oval-shaped green structures that seem to be moving around inside of the cells in an orderly fashion. What general cell type is he MOST likely observing?

a.	prokaryotic and plant
b.	prokaryotic and animal
c.	eukaryotic and plant
d.	eukaryotic and animal

39. Ribosomes are very small nonmembranous organelles that can either exist freely in the cytoplasm or be embedded in the endoplasmic reticulum of a cell. They are associated with the synthesis of

a.	lipids.	c.	nucleic acids.
b.	proteins.	d.	carbohydrates.

40. The smooth endoplasmic reticulum

a.	is the site where lipids destined for other cellular compartments are manufactured.
b.	produces the energy needed to run chemical reactions in the cell.
c.	converts sunlight into chemical energy.
d.	stores water, nutrients, and enzymes.

41. The Golgi apparatus

a.	is the place where a cell’s genetic material is stored.
b.	sorts proteins and lipids and sends them to their final destination.
c.	captures energy from sunlight and sends it to the mitochondria.
d.	creates energy by converting ribosomes to proteins.

42. The boundary that surrounds the contents of the nucleus is the

a.	plasma membrane.	c.	nuclear pore.
b.	nuclear envelope.	d.	cytosol.

43. Which of the following statements is true of chloroplasts?

a.	They produce proteins used by other parts of the cell.
b.	They capture energy from sunlight.
c.	They give an animal cell its shape.
d.	They contain an entire copy of a cell’s genetic material.

44. Human muscle cells need large amounts of ATP to function in the movement of the body, which is why ________ are especially abundant in muscle cells.

a.	mitochondria
b.	ribosomes
c.	smooth endoplasmic reticulum
d.	lysosomes

45. In plants, the epidermis layer functions like a covering of skin to protect the leaf, while vascular bundles carry water and nutrients through the leaf. The palisade mesophyll layer is responsible for most of the photosynthesis that occurs, while the spongy mesophyll layer underneath it aids in the exchange of gases (CO₂ and O₂) and water vapor. In which leaf tissues would one expect to find the highest density of chloroplasts?

a.	epidermis	c.	spongy mesophyll
b.	vascular bundles	d.	palisade mesophyll

46. Which of the following would be the best analogy for the function of the Golgi apparatus?

a.	the machine that assembles a product
b.	a worker in a factory who places labels on products and then packs them into a shipping box
c.	the garbage truck that hauls away the wastes produced as a product is made
d.	the blueprints for making the product

47. A long piece of ribbon wired along both long edges is twisted into a helix and wrapped around individual pipe cleaners that have been rolled into spools; this grouping is then twisted (super coiled) again to condense it. This could be best used as a simple model for a

a.	plasma membrane, where the pipe cleaners represent the phospholipid bilayer and the ribbon represents proteins embedded in the membrane.
b.	cell wall.
c.	mitochondrion.
d.	chromosome, where the pipe cleaners represent bundles of proteins around which the DNA double helix (wired ribbon) is wrapped.

48. A solid waste (garbage) transfer facility that sorts and breaks down garbage into recyclables and waste to be thrown away in the landfill would be a suitable analogy for which cellular organelle?

a.	smooth ER	c.	lysosome
b.	rough ER	d.	nucleus

49. The flexible poles providing structure to a soft-sided tent most closely resemble the

a.	endoplasmic reticulum in a bacterial cell.
b.	Golgi apparatus in a plant cell.
c.	cytoskeleton in an animal cell or other cell without a cell wall.
d.	nucleus in a eukaryotic cell.

50. The endoplasmic reticulum (ER) is a single membrane continuous with the nuclear envelope and a series of interconnected sacs throughout the cell. Why might it be beneficial to the cell for the ER to be continuous with the nuclear envelope? It might be beneficial for the ER and nuclear envelope to be connected because it

a.	takes less energy, DNA, carbohydrates, and phospholipids for the ER to synthesize centrioles.
b.	is easier for messages to get from the nucleus to the ER where proteins and lipids are made for the cell; this would require the use of less energy.
c.	would make it easier for the nucleus to actually carry out cellular respiration.
d.	would make it easier for the ER to carry out photosynthesis.

1. The smallest and most basic units of life are microscopic, self-contained units enclosed by a water-repelling membrane and are called ________.

2. All cells living today came from a preexisting ________.

3. Viruses use their ________ material to take over their host cell’s metabolic machinery to produce the components needed for the virus to reproduce.

4. All cells have a ________ that acts as a barrier separating the cellular components from the external environment.

5. A plasma membrane is constructed of two layers of ________ , organic molecules that have a hydrophilic head and a hydrophobic tail.

6. ________ transport of molecules across a selectively permeable membrane requires the input of energy from the cell, whereas ________ transport of molecules across a selectively permeable membrane does not require the use of cellular energy.

7. When a white blood cell engulfs an entire bacterial cell by surrounding it with plasma membrane and bringing it into the cell in a vesicle, the white blood cell is accomplishing ________.

8. When an amoeba has digested a bit of pond scum in a vesicle and that vesicle then carries the waste products to the amoeba’s cell membrane, fuses with the membrane, and releases the waste products outside of the cell, ________ has occurred.

9. Streptococcus pyogenes can cause a bacterial infection of the throat. Since the bacterium lacks a nucleus or membrane-encased organelles, Streptococcus pyogenes is a(n) ________ cell type.

10. An animal cell that contains an extensive network of ________ is likely to be a key source of lipids and/or hormones important in the development and functioning of that animal.

11. A cell containing a nucleus, mitochondria, Golgi apparatus, both smooth and rough ER, ribosomes, cytoskeleton, a large vacuole, and chloroplasts would be an example of a typical ________ cell.

12. A cell that has numerous ________ is a plant cell that plays an important role in photosynthesizing sugars for the entire plant.

13. A cell surrounded by only a plasma membrane but containing a nucleus, mitochondria, Golgi apparatus, both smooth and rough ER, ribosomes, cytoskeleton, and lysosomes would be an example of a typical ________ cell.

1. Using what you know about cell theory and viruses, explain why viruses are not alive.

2. When scientists such as J. C. Venter and Daniel Gibson engineer a cell constructed with synthetic DNA in the laboratory, do they challenge accepted cell theory? If so, which part of cell theory do they challenge? Briefly explain your answer.

3. Examine the infographic below. Are all bacteria (prokaryotes) likely to be 3 µm in length and all protozoans (eukaryotes) 500 µm in size? Support your answer using information from the infographic.

4. In your own words, briefly point out the primary difference between prokaryotes and eukaryotes, and then explain what might keep viruses from being included in either of these categories.

5. Label the plasma membrane below. Use the following terms: cellular environment, external environment, plasma membrane, hydrophilic heads, hydrophobic tails, energy, water, sugar, and transport protiens.

6. The figure below depicts a transport protein in a plasma membrane. The dark blue molecules represent a protein that is being transported out of the cell. Is the transport of the protein active or passive? Support your answer by describing evidence visible in the figure and stating its significance regarding your answer.

7. The figure below depicts transport proteins in a plasma membrane. Molecules are moving through the plasma membrane. How are the molecules moving across the membrane? Is this movement active or passive? Support your answer by describing evidence visible in the figure and stating its significance regarding your answer.

8. Examine the photo below. This photo shows low-density lipoprotein (LDL) particles bound to receptors on the outside of a cell membrane. You view the same cell later and notice that the LDL particles are now enclosed in vesicles inside of the cell. What would you propose as the explanation for how the LDL particles arrived in their new location? Support your explanation.

9. Explain the process through which cells lining blood vessels bring in pockets of fluids from the bloodstream. Is this process specific or nonspecific?

10. If a white blood cell (WBC) is approximately 18 µm in diameter, which of the cell types or viruses seen in the infographic below would it be large enough to engulf? Describe the process the white blood cell would use to engulf another cell.

11. What additional structures would the cell below need to become a plant cell?

12. There are cells in the human pancreas that produce insulin, a peptide hormone important in the regulation of blood sugar levels by adjusting the metabolism of sugars and fats. Once the pancreas cells have produced the initial peptide (small string of amino acids) component of insulin, it must be finished, packaged, and shipped out of the cell. Which organelles would likely be involved in this process of finishing, packaging, and shipping of a peptide hormone? Include a brief, general description of what happens to the hormone at each organelle and the plasma membrane.

13. Indicate which cell in the figure below is the plant cell and which is the animal cell. Label all cellular structures 1–12 in both cells. Include a brief description of each organelle’s function with its label.

a.	photosynthesis
b.	regulate what moves in and out of cell
c.	structure and support for cell
d.	lipid synthesis
e.	tags proteins for movement
f.	enzymatic breakdown of large molecules
g.	protein synthesis
h.	cellular respiration
i.	water and solute storage
j.	location of DNA
k.	internal organization and structural support

1. central vacuole

2. nucleus

3. cytoskeleton

4. mitochondrion

5. ribosomes

6. rough endoplasmic reticulum

7. smooth endoplasmic reticulum

8. Golgi apparatus

9. lysosome

10. plasma membrane

11. cell wall

12. chloroplast