Download Chapter 4

Biotech Chapters 4-6 Self Test Packet.
50 points
Most of the material in the next few chapters you have had before. We will not be covering this material in class, but it will be needed throughout the
remainder of the course. Feel free to use the book or any other resource of your choosing. This is due upon my return on Tuesday October 26 th in its
completion. Some of these exact questions will be written into a test/quiz next week along with some short answer. You can work on the packet in class
for the next 2 days and then you can finish it up at home.
Chapter 4 – The Origin and Early History of Life
1. The hypothesis of Panspermia proposes that meteors or cosmic dust may have brought _________ to Earth.
2. All living organisms on Earth are characterized by cellular organization, growth, reproduction, and _____________.
3. In Oparin's bubble theory, the chemical-concentrating bubble-like structures were called __________________.
4. Organelles such as the nucleus are not present in __________________ organisms.
5. Prokaryotes were the only organisms for about ___________ billion years after life began on Earth.
6. The early atmospheric condition of primitive Earth was thought to contain ample hydrogen atoms which was conducive
to bond formation and is referred to as a _________________ atmosphere.
7. ____________ are bacteria that are able to grow “without air” or that are poisoned by oxygen.
8. Endosymbiotic bacteria relationships evolved into more complex cell types called _____________, which possessed
nuclear membranes and membrane-bound organelles.
9. Most recent molecular studies have led to the addition of a sixth kingdom, Archaea, containing certain groups of
_____________ with unusual cell walls, membranes and eukaryote-like genetic mechanisms.
10. Through reconstruction of the conditions of the primitive Earth in simulation experiments, scientists have concluded
that certain key _____________ of life could have been created as a by-product of its conditions at birth.
11. Eukaryotic, mostly unicellular (few multicellular), photosynthetic or heterotrophic, such as amoebas and algae, are
classified into a kingdom called _____________.
12. Thomas Cech coined the term ________________ to describe RNA molecules that behaved like enzymes.
____13. Oparin suggested the theory of
A. biogenesis
B. primary abiogenesis
C. natural selection
D. coacervates
E. protobionts
____14. When phospholipid molecules are placed into water, microspheres form spontaneously. These
microspheres are called
A. protons
B. anaerobes
C. archaebacteria
D. eukaryotes
E. coacervates
____15. Early cyanobacteria evolved a form of photosynthesis that permanently changed the Earth’s atmosphere
by releasing which of the following gases?
A. carbon dioxide
B. nitrogen
C. oxygen
D. ozone
E. carbon monoxide
____16. The only “origin of life on Earth” theory or possibility that permits testable scientific hypotheses is
A. alien origin
B. special creation
C. spontaneous origin
D. double helix E. atomic
____17. Spontaneous origin proponents hypothesize that life evolved from inanimate matter. According to this
view, the force leading to life was
A. selection
B. resistance to radiation
C. ability to live on land
D. ability to reproduce
E. all of the above
____18. The age of the Earth according to modern estimations is
A. 8 billion years
B. 4.5 billion years
C. 3.5 billion years
D. 1.5 billion years
E. a few thousand years
____19. The oldest microfossils are of
A. bacteria
B. eukaryotes
C. insects
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D. pollen grains
E. small animals
____20. Life apparently originated on Earth about
A. 1 million years ago
B. 6000 years ago
D. 8 billion years ago
E. 3.5 billion years ago
C. 4.5 billion years ago
____21. According to geochemists which of the following would have been the most unlikely condition on the
primitive Earth?
A. atmospheric cooling
B. crust formation
C. gas cloud encircling the Earth
D. high levels of oxygen
E. water, carbon dioxide, and nitrogen among the early gases
____22. It is generally agreed that the early Earth’s reducing atmosphere contained
A. carbon dioxide, methane, nitrogen gas
B. hydrogen sulfide, water, ammonia
C. more than traces of free oxygen
D. a, b, and c are true
E. only a and b are true
____23. Scientists believe that our atmosphere has progressively changed as some living organisms began to
harness sunlight energy to split water molecules to form complex carbon molecules. This activity led to an
increase in
A. water
B. ammonia
C. oxygen
D. ozone
E. carbon dioxide
____24. The first step in the origin of life is thought to be the formation of organic compounds from atmospheric
components, using all of the following forms of energy except
A. catabolism
B. lightning
C. radioactive decay
D. solar radiation
E. volcanic eruption
____25. An experimental test of the hypothesis to explain the origin of the first organic compounds on Earth might
include all of the following sequential steps (starting with a and proceeding to e) except
A. assemble an atmosphere with H2, CH4, NH3, and H2S
D. increase the temperature of the gases
B. place this atmosphere over liquid water
E. provide energy with electrical spark
C. inoculate with a few bacteria to get the process started
discharges
____26. Among the products of the Miller-Urey experiments and subsequent experiments by others, it was shown
that which of the following could be produced in simulated primitive Earth conditions?
A. ammonia and water
B. amino acids
C. CO2 and H2O
D. formaldehyde and hydrogen sulfide
E. methane and oxygen
____27. Both in Miller-Urey experiments and subsequent experiments by others, it was shown that which of the
following could be produced in simulated primitive Earth conditions?
A. amino acids
B. adenine and other nucleotides
C. living bacteria
D. living eukaryotes
E. only a and b
____28. The characteristics of life include all of the following except
A. complexity
B. death
C. multicellularity
D. sensitivity to environment
____29. All living organisms possess
A. photosynthesis
B. cellular organization C. growth and metabolism
E. only b, c, and d
____30. Coacervates have all of the following except
A. they enclose a small amount of water
B. they divide
D. they have a two-layer outer boundary
E. they show heredity
E. inheritance
D. reproduction and heredity
C. they grow
____31. Oparin, in his theory of “primary abiogenesis” suggested cell predecessors as
A. microspheres
B. protocells
C. protobionts D. coacervates
E. liposomes
____32. It has recently been discovered that enzyme-like catalysis can be carried out not only by enzymes but
also by
A. sugars
B. DNA
C. phospholipids
D. RNA
E.steroids
____33. The most primitive bacteria that exist today are
A. amoeba
B. eubacteria C. archaebacteria
D. algae
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E. nitrogen-fixing bacteria
____34. Bacteria that lack the peptidoglycan in their cell wall are
A. coacervates
B. eukaryotes
C. living fossils
D. archaebacteria
E. fungi
____35. Probably the energy source for the first photosynthetic cells was
A. chemical bond energy
B. lightning
C. radioactive decay
D. geothermal energy
E. sunlight
____36. Oxygen concentration of 1% of 1 billion years ago increased to the present level of 21% because of
photosynthetic activity of
A. fungi
B. cyanobacteria
C. plants
D. protests
E. animals
____37. The oldest fossils of eukaryotes have been estimated to be
A. 6000 years old B. 8 billion years old C. 4.5 billion years old D. 1.5 billion years old
____38. The kingdom not containing eukaryotes is
A. protista
B. archaebacteria
C. fungi
D. animalia
____39. Multicellularity and endosymbiotic relationship is not observed in
A. animalia
B. planta
C. bacteria
D. fungi
E. 1995 years old
E. planta
E. protista
____40. Recent molecular studies have added a new sixth kingdom for prokaryotes that lack peptidoglycan in
their cell walls. It is called
A. yeast kingdom
B. paramecium kingdom
C. amoeba kingdom
D. archaebacteria kingdom
E. eubacteria kingdom
____41. One of the theories about the origin of life is panspermia. Panspermia proposes that
A. Extraterrestrials from extreme distances from Earth seeded the developing planet with primitive life forms,
which eventually evolved into what we know today.
B. Meteors and/or cosmic dust clouds carried various primitive life forms to the Earth, which eventually evolved
into what we know today.
C. Meteors and/or cosmic dust clouds carried various complex organic molecules to the Earth, which eventually
evolved into what we know today.
D. Extraterrestrials from extreme distances from Earth seeded the developing planet with complex organic
molecules, which eventually evolved into what we know today.
E. Spontaneous generation of life followed either an extraterrestrial visit or a meteor deposition of inorganic
molecules.
____42. Of the following primitive Earth conditions and chemical reactions, which one do biochemists know was
important to the formation of amino acids and subsequent formation of complex carbon molecules that are
common to life?
A. There had to be a reducing atmosphere rather than one with oxygen, otherwise formation of those molecules
would have been extremely difficult.
B. There had to be an atmosphere with oxygen rather than a reducing atmosphere, otherwise formation of those
molecules would have been extremely difficult.
C. Cellular respiration was necessary for the reducing atmosphere to form, otherwise photosynthesis would not
have been able to occur.
D. Sulfide molecules from deep-sea vents interacted with available atmospheric oxygen, producing a reducing
atmosphere that would have encouraged amino acid formation.
E. Silicate surfaces provide excellent substrates for cellular respiration, thus increasing the available atmospheric
oxygen, which in turn promoted evolution of inorganic molecules into animate forms.
____43. The “Bubble Theories” all propose that
A. The organic molecules that formed in the soupy mixture of ancient oceans had to find some form of protection
or become disassociated again and again and, thus, bubble formation offered some forms of protection.
B. The organic molecules had to combine with various gases that were present in the pre-biotic atmosphere, such
as methane and nitrogen, to obtain enough buoyancy to reach the surface.
C. The organic molecules united into gaseous envelopes, which covered the surface of the ancient oceans and
thus were propelled farther out into the deeper water by waves.
D. The organic molecules were surrounded by various carbohydrates, which would produce a “lifting effect,”
which would in turn cause the "bubbles" and their trapped organic molecules to rise in the water column.
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____44. Even though archaebacteria are considered the most primitive forms of life so far discovered on Earth,
they still
A. utilize sunlight as a primary energy source
B. utilize ATP as their energy-carrying molecule
C. reproduce normally in oxygen-rich environments
D. create their nuclear membranes from peptidoglycans
E. have difficulty maintaining the cell wall surrounding their cells
____45. Archaebacteria live in hostile-to-life environments. Scientists debate about which ones might be the
“relics” of the first organisms on the Earth. Based on our knowledge of reconstructing the conditions on the early
Earth, which one of these archaebacteria might be the oldest?
A. methanogens
B. extreme halophiles
C. extreme thermophiles
D. extreme peptidoglycans
E. cyanobacteria
____46. The fossil record reflects a change in cells and cell structures dating at least 1.5 billion years ago. There
was a shift toward a cell type referred to as eukaryotic. Organisms described as eukaryotic have which of the
following in common?
A. They are all anaerobic.
B. They are all autotrophic.
C. They all utilize photosynthesis.
D. They all have a membrane-bound nucleus.
E. They are all unicellular.
____47. Diversity among the vast numbers of organisms that have arisen on the Earth can be attributed to all the
following except
A. sexual reproduction
B. multicellularity
C. a membrane-bound nucleus
D. for the development of the endoplasmic reticulum
E. for the ability to utilize the same gene sequences to produce their proteins
____48. Which of the following was demonstrated by the Miller-Urey experiment?
A. Life began in the oceans.
B. Life can be started experimentally in the laboratory.
C. Organic molecules important to life could have been formed from a vast array of simple chemicals.
D. Life began on the pre-biotic Earth 3.5 billion years ago.
____49. One day while Dr. Feelgood was working in his taxonomic laboratory, a package arrived with the
following label: “Beware, the contents of this package contains a eukaryotic, multicellular, nonmotile,
nonphotosynthetic life form. Open with extreme caution.” Dr. Feelgood quickly closed the doors and windows of
his laboratory and opened the package. To which two kingdoms of life could this life form belong?
A. Archaebacteria
B. Animalia
C. Fungi
D. Plantae
E. Protista
____50. Archaebacteria share all of the following characteristics except
A. unicellular structure
B. considered prokaryotes
C. contain a peptidoglycan cell wall
D. include human pathogens
E. c and d are correct
____51. The current bubble hypothesis for the evluation of life does not include
A. volcanic eruptions under the ocean releasing gases in bubbles
B. bubbles of oxygen mixed with volcanic produced bubbles
C. complex organic molecules mixed into the ocean from rain
D. energy sources included UV, radiation, and lightening
E. gases concentrated inside bubbles
____52. Many scientists believe that life on Earth originated
A. on the surface of clay particles
B. at deep-sea vents
D. in the foam produced at the ocean’s edge
E. all of the above
C. under the frozen ocean
____53. Archaebacteria are most likely to be found today in
A. hot sulfur springs
B. in the Dead Sea
C. in a small pond in the Tropical Rain Forest
D. a and b only
E. all of the above
54. Match each of the following.
__________A. Names of early environmentally isolated, chemical concentrating structures.
1.
________B. Cellular organelle containing organisms; include all organisms except bacteria.
2.
_________C. Blue-green algae; a type of bacteria important in the history of life on Earth.
3.
__________D. The most primitive bacteria that exist today; methane producing bacteria;
4.
absence of peptidoglycan cell-wall.
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archaebacteria
cyanobacteria
protobionts
eukaryotes
Chapter 5 Cell Structure
1. Plasma ________ encloses the cell and separates its contents from the surroundings.
2. A semi-fluid matrix called the _________ occupies the area between the nucleus and the plasma membrane.
3. All _____ contain a plasma membrane.
4. The cell theory states that all of the ________ on earth are individual cells or aggregates of cells.
5. The interior of eukaryotic cells contain numerous membrane-bound structures called ___________.
6. The _________ of a eukaryotic cell contains most of the cell's hereditary apparatus, which isolates it from the
rest of the cell.
7. A distinctive feature of eukaryotes is the organization of their chromosomal DNA which is tightly packaged with
proteins into a membrane-bound structure called a _______.
8. The delivery system of eukaryotic cells called the ______ complex can collect, package, modify, and transport
molecules.
9. The _________ is not only responsible for the cell's shape and movement, but it also provides a scaffolding at
certain locations of the cytoplasm for some enzymes and macromolecules.
10. ___________ is the generally accepted evolutionary process which created the organelles, chloroplasts, and
mitochondria.
11. Even though they were similarly created by endosymbiosis, ___________ are important in respiration, while
chloroplasts are involved in photosynthesis.
12. Many eukaryotic cells possess flagella or cilia, which have the characteristic ______ arrangement of
microtubules.
13. Microfilaments such as actin, microtubules, and the intermediate filaments form the cell-supporting structure
called the ______________.
14. As a cell’s size increases, the _____________ increases much more rapidly than its surface area.
15. Animal cells excrete glycoproteins outside of the plasma membrane to produce an __________________
which is directly linked to the cytoskeleton.
____16. Small cells function more effectively, because as cells become larger their surface area to volume ratio
A. increases
B. decreases C. stays the same
D. is squared E. is cubed
____17. Membrane-bound organelles that contain powerful enzymes found in cells are known as
A. lysosomes B. plastids
C. vacuoles
D. liposomes E. ribosomes
____18. The proteins of the plasma membrane are in large part responsible for the cell's ability to interact with its
environment. They act as or are involved in all of the following except
A. channel
B. recognition
C. reception
D. transport
E. packaging (histones)
____19. The genetic material of which kind of cells is included in a single, circular molecule of DNA devoid of any
histone proteins?
A. bacteria
B. protozoa
C. insects
D. flowering plants
E. yeasts
____20. Who first described cells?
A. Darwin
B. Golgi
C. Linnaeus
D. Hooke
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E. Leeuwenhoek
____21. Schlieden and Schwann stated the “cell theory,” which in its modern form includes all of the following
postulates except
A. All organisms are composed of one or more cells.
B. All cells need oxygen.
C. Cells are the smallest living things.
D. Cells arise only by division of a previously existing cell.
E. Cells vary in size and shape.
____22. The chromosomal hereditary material is packaged in this organelle in eukaryotic cells but not in
prokaryotic cells. This organelle is
A. mitochondria
B. chloroplasts
C. plasma membrane
D. nucleus
E. centrioles
____23. The peptidoglycan of the bacterial cell wall contains a carbohydrate matrix linked together by short
chains of
A. amino acids
B. fatty acids
C. nucleotides
D. water molecules
E. steroids
____24. A very common method of distinguishing the bacteria takes advantage of the thickness of the
peptidoglycan layer in the cell wall. This method of differential staining of cells is called
A. positive staining
B. negative staining
C. Gram staining
D. neutral staining
E. prokaryotic staining
____25. Prokaryotic cell movement is attributed to the
A. capsule
B. ribosomes
C. pili
D. nucleoid area
____26. Photosynthetic bacterial membranes are located in the
A. nuclei
B. chloroplasts
C. cell wall
D. plasma membrane
E. flagella
E. plasmids
____27. Plant cells often have a large membrane-bound sac that is used for storing water and other substances.
This organelle is called
A. nucleus
B. chloroplast
C. Golgi body
D. centriole
E. central vacuole
____28. Which of the following is not bounded by membranes?
A. endoplasmic reticulum
B. microbody
C. Golgi body
D. nucleoid
E. nucleus
____29. Some of the functions of the eukaryotic organelles are performed in bacteria by the
A. plasma membrane B. nucleoid area
C. cell wall
D. capsule
E. flagella/cilia
____30. All of the following about flagella of bacteria are true except
A. they are used in locomotion
B. they are used in feeding
C. they have similar function as mitochondria of eukaryotic cells
D. there may be more than one per cell
E. they are attached in between the cell wall and the membrane
____31. The cytoplasmic space in eukaryotic cells is occupied by many diverse membrane-bound structures with
specific cellular functions. These are called
A. flagella
B. organelles C. cilia
D. chromosomes
E. receptors
____32. Which of the following is not present in all eukaryotic cells?
A. endoplasmic reticulum
B. ribosome
C. plasma membrane
____33. Some ribosomes are embedded into
A. chromosomes
B. smooth endoplasmic reticulum
D. histones
E. vacuoles
____34. Ribosomes are
A. only DNA molecules
D. only protein molecules
D. cell wall
E. Golgi bodies
C. rough endoplasmic reticulum
B. only RNA molecules
C. single, naked, and circular chromosomes
E. large molecular aggregates of protein and RNA
____35. The eukaryotic organelle that is directly involved in the transport of proteins synthesized on the surface of
the rough ER is called
A. mitochondria
B. vacuole
C. cytoskeleton
D. Golgi complex
E. nucleus
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____36. Lipid synthesis occurs in which eukaryotic organelle?
A. rough ER
B. smooth ER C. lysosomes
D. mitochondria
E. nucleolus
____37. Many hormones induce changes in cells by first binding to plasma membrane
A. marker proteins
B. pores
C. rough ER
D. channels
E. surface receptors
____38. In eukaryotes, mitochondria are the organelles primarily involved in
A. energy release/capture
B. phospholipid assembly
C. export of enzymes
E. protein synthesis
D. lipid synthesis
____39. Which structure is the repository of the genetic information that directs all of the activities of the cell?
A.ER
B. mitochondria
C. nucleus
D. chloroplasts
E. centriole
____40.Nuclear pores apparently permit the passage of only
A. chromosomes outward
B. glucose molecules outward
D. proteins inward and outward, but RNA only outward
C. assembled DNA molecules outward
E. sodium ions inward, potassium ions outward
____41.Nucleolus of the nucleus is the site of
A. protein synthesis
B. ribosome assembly
C. chromosome replication
D. lipid synthesis
E. uncoiling and unraveling of chromosomes
____42. Chromosomes can be condensed into compact structures, visible with the light microscope, but usually
only
A. after the cell is dead
B. during cell division
C. while the DNA is being copied into RNA
D. while the proteins are being assembled
E. while the nuclear pores are open
____43. Flattened sacks of membranes apparently involved in the packaging and export of molecules
synthesized in the cell are known as
A. Golgi bodies
B. microbodies
C. pinocytic vesicles
D. vacuoles
E.chromosomes
____44. Lysosomes are vesicles bounded by membranes that contain oxidative enzymes. Their functions include
all of the following except they
A. catalyze the rapid breakdown of macromolecules
B. break down old organelles
C. eliminate substances taken into the cell by phagocytosis
D. digest phagocytized pathogens
E. allow bacteria to pass through unaffected
____45. Peroxisomes in animal cells, and glyoxosomes in plant cells are examples of
A. chromosomes
B. lysosomes
C. microbodies
D. nucleosomes
E. ribosomes
____46. Mitochondria and chloroplasts are the other organelles besides the nucleus that contain
A. genes
B. pores
C. channels
D. plasma membranes
E. pigments
____47. The organelle involved in the oxygen-requiring process by which the energy in macromolecules is stored
in ATP is the
A. nucleus
B. lysosome
C. ER D. mitochondria E. chloroplasts
____48. The endosymbiotic theory is supported by the finding of non-nuclear DNA in which of the following
organelles?
A. lysosomes
B. ER
C. mitochondria
D. chloroplasts
E. both in c and d
____49. The distinctive feature of chloroplasts is that they contain a green pigment called
A. Gram stain B. chlorophyll C. hemoglobin D. chromatin
E. keratin
____50. Which of the following is not found in the cytoskeleton?
A. actin filaments B. intermediate filaments C. spindle fibers D. microtubules
____51. Centrioles are organelles which have
A. a barrel shape
B. paired structures
D. microtubule assembly function
E. none of the above
C. composed of nine triplets of microtubules
E. all of the above
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____52. The functions of the cytoskeleton include
A. providing the cell shape
B. providing a scaffolding for the enzymes in certain areas of the cell
C. organizing the cell's activities
D. providing movement of molecules in the cell
E. all of the above
____53. Cell crawling is essential for which of the following?
A. cancer spreading
B. inflammation
C. wound healing
____54. Bacteria are generally
A. 1 to 2 centimeters thick
B. 1 to 2 millimeters thick
D. 1 to 2 nanometers thick
E. 1 to 2 meters thick
D. clotting of blood
E. all of the above
C. 1 to 2 micrometers thick
____55. The electron microscope can magnify an object typically
A. ten times bigger
B. one hundred times bigger
C. one thousand times bigger
D. tens of thousand times bigger
E. hundreds of thousand times bigger
____56. A team of researchers is writing a grant for a microscope to use in their research on the external
structures on the dorsal surface of a spider mite. The specific region on the mite’s back seems to be the habitat of
an even smaller mite. These mites are extremely tiny and only one microscope with very high magnification can
be purchased. Based on the information given, which type of microscope would you suggest?
A. transmission electron microscope
B. scanning electron microscope
C. binocular compound light microscope
D. monocular compound light microscope
E. dissecting microscope
____57. A computer program is being written by one of your friends to design the “perfect” spherical cell. She
asks you about the sizes of cells and if there are any ratios or mathematical factors that she should use in her
program. You reply,
A. “No, there are none that I am aware of; cells can be any size as long as they have a plasma membrane.”
B. “Yes, make sure that you include in the program that as the cell's diameter increases, the surface area of the
cell and the cell volume increases by the square root of the cell's diameter.”
C. “Yes, make sure that you include in the program that as the cell's diameter increases, the surface area of the
cell increases by squaring the diameter of the cell, while the cell volume increases by cubing the diameter of the
cell.”
D. “No, as long as you clearly state the type of cell that is required—for example, a red blood cell or a bone cell—
otherwise you will have to set up a differential equation that considers the nuclear diameter.”
____58. A cytologist is examining a tissue under an electron microscope. He notices in particular that the
endoplasmic reticulum of each cell is extremely rough in appearance and of course knows that the rough
appearance is because of the ribosomes embedded there. He is curious about why there are so many ribosomes.
You can help. Your response would be,
A. “This tissue exports lipids and is very involved with mRNA production, which of course is used in protein
synthesis.”
B. “This tissue exports proteins to other areas of the body.”
C. “This tissue has obviously been exposed to the new protein diet supplements that are so popular these days
and has been recruited to make more protein.”
D. “This tissue exports various nucleic acids, hence the large number of ribosomes present on the endoplasmic
reticulum in each of those cells.”
____59. One of the relationships that exists between ribosomes and lysosomes is that
A. ribosomes produce enzymes that could be stored in lysosomes
B. ribosomes produce lipids that could be stored in lysosomes
C. lysosomes are located near ribosomes on the surface of the endoplasmic reticulum
D. lysosomes are produced by ribosomes and therefore contain proteins that were synthesized at the ribosomes
____60. A cell physiologist treats a cell with a chemical that prevents entry of amino acids. Which organelle will
be affected the most?
A. mitochrondia
B. lysosome
C. nucleus
D. ribosome
E. Golgi apparatus
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____61. A cell biologist has developed a new drug that will block the cis face of the Golgi apparatus. If eventually
approved by the FDA, she wants to use this new drug to aid cancer patients. What specifically will this drug
prevent from happening inside a cancer cell?
A. the synthesis of proteins or lipids on the endoplasmic reticulum
B. the movement of the lipids and proteins from the endoplasmic reticulum to the Golgi apparatus
C. the blockage of proteins and lipids on the endoplasmic reticulum
D. the prevention of ATP synthesis by blocking pyruvate formation on the trans face of the Golgi apparatus
____62. A cell biologist treats a cell so that oxygen cannot diffuse across the membrane. Which organelle will be
directly affected?
A. mitochrondia
B. lysosome
C. nucleus
D. ribosome
E. Golgi apparatus
____63. Plants, fungi, and bacteria share which one of the following characteristics?
A. cell walls
B. nuclear membranes C. nuclei
D. lysosomes E. vesicles
____64.Which of the following is not visible by use of a light microscope?
A. paramecium
B. bacterium
C. large virus D. red blood cell
E. eukaryotic nucleus
____65. A plant and animal cell both contain
A. nucleus
B. Golgi apparatus
C. aysosome
E. all of the above
D. a and b only
____66. All of the following are considered to be part of the endomembrane system except
A. mitochondria
B. Golgi Apparatus
C. rough endoplasmic reticulum
D. plasma membrane E. transport vesicles
____67. Prokaryotic, Animal and Plant cells all possess
A. ribosomes B. plasma membrane C. microtubules
D. b and c only
68. Match each of the following.
__________A. DNA in a membrane-bound structure.
1.
__________B. Cell wall present, at least in some members of the group.
2.
__________C. Cell wall of nitrogen-containing carbohydrate, cross-linked with 3.
short
amino acid chains.
__________D. Employ RNA and protein as the only hereditary materials.
4.
__________E. Large cells, nucleus, inner membrane, and one or the other
5.
compartments.
E. a and b only
prokaryotes only
eukaryotes only
both prokaryotes and eukaryotes
neither prokaryotes nor eukaryotes
not consistently
Chapter 6 - Membranes
1. The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called
____________.
2. Due to the repellent nature of the polar water molecules, the ________ tails of the phospholipids are
sequestered together.
3. While water continually orients phospholipids into a lipid bilayer, it does not fix the lipids permanently into
position. Thus they are considered _______ in nature.
4. ________ is the net movement of substances to regions of lower concentration.
5. Osmosis is the diffusion of water across a membrane in response to the concentration of one or more of the
________.
6. Because a given channel or carrier will transport only certain kinds of molecules and ions, the plasma
membrane is said to be ___________.
7. The net movement of a solute across the plasma membrane toward a region of lower concentration, by means
of specific channels or carriers, is called _________.
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8. The type of active transport where protons are pumped out of the cell or into an organelle against their
concentration gradient is called ___________.
9. Glycoproteins and glycolipids are examples of _____________________ associated with the cell membrane.
10. Both active transport and facilitated transport utilize specific ______________ proteins embedded in the cell
membrane.
11. Osmosis occurs as water can cross the lipid bilayer through __________________, specialized channels for
water movement.
____12. The plasma membrane is a thin sheet of lipid embedded with larger molecules
A. called proteins
B. called carbohydrates
C. called polymers
D. called nucleotides
E. of sodium and potassium ions
____13. Membrane proteins are not very soluble in water, because they possess long stretches of non-polar
amino acids that
A. are too long to interact with the water molecules
B. are hydrophobic
C. are transmembranal
D. are hydrophilic
E. serve as transport channels
____14. Proteins that function as passageways through which substances and information crosses the
membrane are called
A. junction proteins
B. carrier proteins
C. hydrophilic proteins
D. hydrophobic proteins
E. transmembrane proteins
____15. If a cell has the same concentration of dissolved molecules as of its outside environment, the cell’s
condition is called as being
A. isotonic
B. hypertonic C. hypotonic
D. hydrophobic
E. hydrophilic
____16. A type of transport of a solute across a membrane, up its concentration gradient, using protein carriers
driven by the expenditure of chemical energy is known as
A. osmosis
B. diffusion
C. facilitated transport D. active transport
E. exocytosis
____17. The cell’s transactions with the environment mediated by its plasma membrane include all of the
following except
A. ingesting food as molecules and sometimes as entire cells
B. returning waste and other molecules back to the environment
C. responding to a host of chemical cues
D. directing the synthesis of various food-digesting proteins
E. passing of messages to other cells
____18. Which of the following properties is not true of membrane phospholipids?
A. The hydrophobic tails are oriented towards the interior.
B. The hydrophilic heads are oriented towards the exterior.
C. Only the saturated fatty acids are always present.
D. Once they are incorporated they remain in the membrane permanently.
E. The bilayers made up of them are randomly interspersed with proteins.
____19. The fluid nature of the membranes is attributed to a lateral movement of
A. protein channels
B. phospholipid molecules
C. antigen molecules
D. pumps such as the proton pump
E. the entire lipid bilayer
____20. Some proteins of the plasma membrane extend across the entire width of the membrane. These have
been known to function as
A. structural proteins
B. recognition proteins
C. channels
D. cell shape determinants
E. cell division triggers
____21. On the outer surface of the plasma membrane there are marker molecules that identify the cell-type.
Often these molecules are
A. ATP
B. amino acids
C. nucleotides D. carbohydrate chains
E. inorganic ions
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____22. Which of the following protein classes are not found as membrane proteins?
A. transport channels B. hormones
C. receptors
D. enzymes
E. identity markers
____23. The part of a membrane protein that extends through the phospholipid bilayer is primarily composed of
amino acids that are
A. highly polar
B. negatively charged C. non-polar
D. positively charged
E. water soluble
____24. The following are all functions of a typical plasma membrane except
A. transport of water and bulk material
B. selective transport of certain molecules and material
C. reception of information
D. expression of cellular identity
E. be permanent in composition
____25. The movement of substances to regions of lower concentration is called
A. active transport
B. diffusion
C. osmosis
D. pumping
E. exocytosis
____26. If two solutions have unequal concentrations of a solute, the solution with the lower concentration is
called A. isotonic
B. hypertonic C. hypotonic
D. hypnotic
E. osmosis
____27. In bacteria, fungi, and plants the high internal pressure generated by osmosis is counteracted by the
mechanical strength of their
A. plasma membranes B. organelles C. cytoskeletons
D. cell walls
E. flagella
____28. Some single-celled eukaryotes remove the water entering by osmosis with a process called extrusion
which involves
A. mitochondria
B. cell walls
C. Golgi bodies
D. micro bodies
E. contractile vacuoles
____29. The actual transport of protons by the proton pump is mediated by a transmembrane protein which
undergoes a change in its
A. conformation
B. amino acid sequence
C. net charge
D. solubility
E. immunity
____30. The process often thought of as “cell eating” is
A. osmosis
B. pinocytosis
C. phagocytosis
D. diffusion
____31. Carrier-mediated transport is also called
A. facilitated diffusion B. active transport
C. exocytosis
D. endocytosis E. phagocytosis
____32. Osmosis can only occur if water travels through the
A. cell wall
B. semi-permeable membrane C. vacuole
D. ER E. cytoskeleton
____33. Cell-walled organisms cannot carry out
A. exocytosis B. active transport
C. osmosis
D. diffusion
E. active transport
E. endocytosis
____34. The type of diffusion that is specific and passive, and which becomes saturated if all of the protein
carriers are in use is
A. exocytosis B. facilitated diffusion C. active transport
D. endocytosis E. osmosis
____35. The type of transport that is specific, which requires specific carrier molecules and energy is
A. exocytosis B. facilitated diffusion C. active transport
D. endocytosis E. osmosis
____36. In a single sodium-potassium pump cycle, ATP is used up with the result that
A. 3 sodium ions leave and 2 potassium ions enter
B. 1 sodium ion enters and 1 potassium ion leaves
C. 1 sodium ion leaves and 1 potassium ion enters
D. 3 sodium ions enter and 2 potassium ions leave
E. sodium and potassium ions enter and water leaves
____37.The accumulation of amino acids and sugars in animal cells occurs through the
A. ATP pump B. sodium-potassium pump
C. glucose pump
D. coupled transport
____38. Cholesterol functions in the plasma membrane to
A. transport ions
B. serve as an energy molecule C. maintain fluidity
E. maintain hypertension
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E. proton pump
D. mediate steroid action
____39. A phospholipid molecule has a polar and a nonpolar end. Because of this, water molecules form
A. polar bonds with the nonpolar end of the phospholipid molecule
B. polar bonds with the polar end of the phospholipid molecule
C. hydrogen bonds with the nonpolar end of the phospholipid molecule
D. hydrogen bonds with the polar end of the phospholipid molecule
E. covalent bonds with the nonpolar end of the phospholipid molecule
____40. The Fluid Mosaic Model proposed by Singer and Nicolson in 1972 included that
A. The cell membrane was composed of lipids and proteins.
B. The cell membrane was composed of a phospholipid bilayer between two layers of globular proteins.
C. The cell membrane was composed of a phospholipid bilayer with globular proteins actually inserted into the
bilayer.
D. The cell membrane was composed of a phospholipid bilayer but the polar ends of the phospholipid molecules
were reversed.
____41. Membrane proteins serve many functions. One of the functions is transportation of substances across
the membrane. If a cell biologist placed cells into an environment in which a chemical has been added that blocks
the function of these transport proteins, which process will be blocked?
A. active transport
B. osmosis
C. diffusion
D. phagocytosis
E. pinocytosis
____42. For the process of diffusion to occur, molecules must
A. Move from areas of high concentration to areas of lesser concentration until an equilibrium is reached.
B. Move from areas of low concentration to areas of higher concentration until an equilibrium is reached.
C. Remain stationary until their molecular motion allows for an equilibrium to be reached.
D. Move from areas of high concentration to areas of lesser concentration until facilitated transport can assist the
molecular equilibrium.
E. Move from areas of high concentration to areas of lesser concentration until an equilibrium is reached by active
transport.
____43. Facilitated diffusion is an important method for cells in obtaining necessary molecules and removing
other ones. Requirements for facilitated diffusion include which of the following?
A. The carrier molecule must be specific to the molecule that is transported. The direction of movement is always
with the concentration gradient, never against the gradient.
B. The carrier molecule is nonspecific to the molecule that is transported. The direction of movement is always
with the concentration gradient, never against the gradient.
C. The carrier molecule is nonspecific to the molecule that is transported. The direction of movement is always
against the concentration gradient, never with the gradient.
D. The carrier molecule must be specific to the molecule that is transported and an ATP molecule must be
attached to the specific carrier. The direction of movement is always against the concentration gradient, never
with the gradient.
____44. If a blood research laboratory is attempting to collect the content of human red blood cells, the
researchers should use which of the following types of solutions to cause blood cell lysis (bursting)?
A. hyperosmotic
B. isosmotic
C. hypoosmotic
____45. One day during the summer you and some friends made ice cream using an electric ice cream maker. A
few days later you noticed a yellow circle of dead grass where the ice cream freezer had been placed. What
happened?
A. The ice and salt mixture that spilled out when the freezer was moved froze the grass.
B. The grass was frost bitten by the ice and salt mixture that spilled out when the freezer was moved.
C. The ice and salt mixture was isosmotic to the grass cells and caused the yellow circle of dead grass.
D. The ice and salt mixture was hyperosmotic to the grass cells and caused the yellow circle of dead grass.
E. The ice and salt mixture was hypoosmotic to the grass cells and caused the yellow circle of dead grass.
____46. Which of the following is not a component of an animal cell membrane?
A. phospholipids
B. polynucleotides
C. aquaporins D. glycolipids E. cholesterol
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____47. As a scientist you perform an experiment in which you create an artificial cell with a selectively
permeable membrane through which only water can pass. You put a 5M solution of glucose into the cell and you
place that into a beaker of water. What observations do you expect to see?
A. Water moves out of the cell.
B. Glucose moves out of the cell.
C. No net change in cell weight.
D. Water moves into the cell.
E. Glucose moves into the cell.
____48. As a scientist you perform an experiment in which you create an artificial cell with a selectively
permeable membrane through which only water can pass. You put a 5M solution of glucose into the cell and you
place that into a beaker of 10M glucose. What observations do you expect to see?
A. Water moves out of the cell.
B. Glucose moves out of the cell.
C. No net change in cell weight.
D. Water moves into the cell.
E. Glucose moves into the cell.
____49. The turgor pressure observed in plants is a direct result of the plant cells being _________________ to
their environment.
A. hypoosmotic
B. isosmotic
C. osmosis
D. hyperosmotic E. None of the above
____50. Which of the following is not a part of the Sodium-Potassium Pump?
A. Three sodium ions bind to the cytoplasmic side of the protein.
B. Three sodium ions are translocated out of the cell.
C. Phosphate facilitates potassium ion binding to transport protein.
D. Two potassium ions are transported into the cell.
E. ATP binds to the protein which becomes phosphorylated (ADP is released).
51.Match each of the following.
_________A.
Fluid, hydrophobic barrier to the passage of proteins polar molecules.
1.
_________B.
May serve as cell surface markers.
2.
_________C.
Channels of the sodium-potassium pump.
3.
_________D.
May act as cell surface receptors.
4.
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exterior
glycolipids
lipid bilayer
transmembrane proteins