Author: Biology Junction Team

PCC Prokaryotes

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PCC Prokaryotes

 

 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 1.
Eubacteria and archaebacteria differ in
a.
 the presence of a nucleus.
c.
 size.
b.
 the makeup of their cell walls.
d.
 the presence of a cell wall.
 2.
Escherichia coli is classified as a(an)
a.
 archaebacterium.
b.
 eubacterium.
c.
 eukaryote.
d.
 virus.
 3.
Which of the following is NOT a way in which archaebacteria and eubacteria differ?
a.
 Archaebacteria lack an important carbohydrate found in the cell walls of eubacteria.
b.
 The two groups have very different membrane lipids.
c.
 Archaebacteria have gene sequences that are similar to those of eukaryotes.
d.
 Archaebacteria follow the lytic cycle, while eubacteria follow the lysogenic cycle.
 4.
Which of the following are members of the kingdom Archaebacteria?
a.
 methanogens
c.
 eukaryotes
b.
 eubacteria
d.
 E. coli

nar001-1.jpg

Figure 19–1
 5.
The structure in Figure 19–1 represents a(an)
a.
 virus.
c.
 methanogen.
b.
 archaebacterium.
d.
 eubacterium.
 6.
Which structure or structures shown in Figure 19–1 have key differences in eubacteria and archaebacteria?
a.
 A, B, C
c.
 D only
b.
 A, B, E
d.
 A only

nar002-1.jpg

Figure 19–2
 7.
Which cell shape in Figure 19–2 is called a coccus?
a.
 A
c.
 C
b.
 B
d.
 none of the above
 8.
Which of the following can survive either with oxygen or without it?
a.
 obligate aerobes
c.
 facultative anaerobes
b.
 obligate anaerobes
d.
 bacteriophages
 9.
Some bacteria are able to survive unfavorable conditions by forming
a.
 photoautotrophs.
c.
 coccus.
b.
 capsids.
d.
 endospores.
 10.
Which of the following is(are) used to identify prokaryotes?
a.
 cell shape
c.
 the way prokaryotes obtain energy
b.
 the way prokaryotes move
d.
 all of the above
 11.
Where are you likely to find a photoautotroph?
a.
 in your refrigerator
b.
 in the darkness of the ocean
c.
 in your digestive system
d.
 near the surfaces of lakes, streams, and oceans
 12.
Unlike photoautotrophs, chemoautotrophs obtain energy
a.
 directly from the sun.
c.
 indirectly from organic molecules.
b.
 directly from inorganic molecules.
d.
 indirectly from other organisms.
 13.
A method called Gram staining is used to tell
a.
 what shape a prokaryote has.
b.
 how a prokaryote obtains energy.
c.
 what kind of cell wall a prokaryote has.
d.
 whether a prokaryote has flagella.
 14.
Which of the following describes a role of bacteria in the environment?
a.
 carrying out photosynthesis
c.
 fixing nitrogen
b.
 recycling nutrients
d.
 all of the above
 15.
Bacteria that break down the nutrients in dead matter into simpler substances that are taken up by plant roots are called
a.
 endospores.
c.
 photoautotrophs.
b.
 flagella.
d.
 decomposers.
 16.
Nitrogen fixation involves each of the following EXCEPT
a.
 soybeans.
c.
 fertilizer.
b.
 Rhizobium.
d.
 nodules on roots.
 17.
Which of the following is produced when bacteria break down complex compounds in sewage?
a.
 carbon dioxide gas
c.
 nitrogen
b.
 purified water
d.
 all of the above
 18.
Humans use bacteria to
a.
 clean up small oil spills.
c.
 synthesize drugs.
b.
 mine minerals from the ground.
d.
 all of the above
 19.
Bacteria living in extreme environments may be a good source of
a.
 antibiotics.
c.
 nitrogen-fixing bacteria.
b.
 heat-stable enzymes.
d.
 Gram stains.
 20.
Which of the following is a way that bacteria cause disease?
a.
 by capsids
c.
 by conjugation
b.
 by nitrogen fixation
d.
 by releasing toxins
 21.
Bacteria that cause disease are called
a.
 viruses.
c.
 endospores.
b.
 pathogens.
d.
 antibiotics.
 22.
Food stored in a refrigerator will keep longer because the bacteria that spoil food
a.
 die at low temperatures.
b.
 take longer to multiply at low temperatures.
c.
 require light to live.
d.
 grow more slowly in the dark.
 23.
Which of the following is a characteristic of bacteria that is key to keeping them under control?
a.
 Most bacteria cannot survive high temperatures for long periods.
b.
 Most bacteria are resistant to harmful chemicals.
c.
 Most bacteria form endospores when subjected to harsh conditions.
d.
 Most bacteria do not cause food to spoil.
 24.
Which of the following will NOT kill bacteria?
a.
 refrigeration
c.
 chemical disinfection
b.
 boiling
d.
 frying
 25.
The chromosomes of bacteria
a.
 contain numerous types of organelles.
b.
 are divided into compartments.
c.
 vary in number, depending on the species of bacteria.
d.
 contain a single circular piece of DNA.
 26.
Structures found in bacterial cells but not in eukaryotic cells are
a.
 nuclei.
c.
 membrane-bound organelles.
b.
 linear chromosomes.
d.
 circular chromosomes.
nar003-1.jpg
 27.
Refer to the illustration above. Organism B has a shape similar to that of
a.
 Micrococcus.
c.
 Streptococcus.
b.
 Bacillus.
d.
 Leptospira.
 28.
Refer to the illustration above. The shape represented by Organism A applies to the bacterial genus
a.
 Streptococcus, which causes strep throat.
b.
 Leptospira, which can cause urinary tract infections in humans.
c.
 Bacillus, which produces antibiotics.
d.
 Penicillium, which produces penicillin.
 29.
Refer to the illustration above. The shape represented by Organism C is called
a.
 a coccus.
c.
 a bacillus.
b.
 a spirillum.
d.
 filamentous.
 30.
Bacteria often have small extra loops of DNA called
a.
 nucleoids.
c.
 plasmids.
b.
 pili.
d.
 prions.
 31.
Cell organelles that Escherichia coli and other bacteria have in common with eukaryotes are
a.
 chloroplasts.
c.
 nuclei.
b.
 mitochondria.
d.
 ribosomes.
 32.
It is important to distinguish between Gram-positive and Gram-negative bacteria in diagnosing a bacterial infection because
a.
 Gram-negative and Gram-positive bacteria differ in their response to different antibiotics.
b.
 Gram-positive bacteria never cause fatal diseases.
c.
 Gram-positive bacteria destroy antibiotics, preventing them from working.
d.
 Gram-positive bacteria do not respond to many antibiotics.
 33.
Bacterial cells have
a.
 a cell wall only.
b.
 a cell membrane only.
c.
 both a cell membrane and an outer cell wall.
d.
 a cell wall inside their cell membrane.
 34.
Escherichia coli is an example of a bacterium that has
a.
 a thin layer of peptidoglycan in its cell wall.
b.
 a thick layer of peptidoglycan in its cell wall.
c.
 a shape called a coccus.
d.
 a cell wall but no cell membrane.
 35.
Cyanobacteria are photoautotrophs because they require
a.
 oxygen.
c.
 inorganic chemicals.
b.
 carbon dioxide.
d.
 light.
 36.
Nitrogen-fixing bacteria
a.
 repair nitrogen-damaged soybean roots.
b.
 damage the environment by using atmospheric oxygen to produce toxic nitrogen compounds.
c.
 convert atmospheric nitrogen into a usable form of nitrogen.
d.
 convert ammonia in the soil into nitrogen gas.
 37.
Bacterial cells such as Escherichia coli transfer pieces of genetic material in a process called
a.
 binary fission.
c.
 conjugation.
b.
 mitosis.
d.
 sexual reproduction.
 38.
Bacterial endospores
a.
 are formed when there is plenty of available food.
b.
 allow certain species to survive harsh environmental conditions.
c.
 are similar to human tumors.
d.
 can cause growth abnormalities in plants.
 39.
A chain of round bacteria would be called:
a.
 spirilla.
b.
 diplococci.
c.
 bacilli.
d.
 streptococci.
e.
 streptobacilli.
 40.
Rod-shaped bacteria are called:
a.
 streptococci.
b.
 bacilli.
c.
 diplococci.
d.
 vibrio.
e.
 spirochete.
Figure 23-02
Use the figure below to answer the corresponding questions.nar004-1.jpg
 41.
The structure in Figure 23-02 labeled C is:
a.
 a ribosome.
b.
 the plasma membrane.
c.
 the capsule.
d.
 the cell wall.
e.
 the flagellum.
 42.
What is the function of the structure labeled A in Figure 23-02?
a.
 to adhere to surfaces or other bacteria
b.
 to prevent phagocytosis
c.
 support and protection in hypotonic conditions
d.
 transmission of DNA between bacteria
e.
 locomotion
 43.
The walls of Eubacteria contain peptidoglycan, which is:
a.
 lipids crosslinked with sugars.
b.
 sugars crosslinked with proteins.
c.
 a protein.
d.
 a lipid.
e.
 a polysaccharide.
 44.
Penicillin works most effectively against gram-positive bacteria because:
a.
 penicillin affects cell membranes.
b.
 they have a thick peptidoglycan cell wall and penicillin affects the synthesis of peptidoglycans.
c.
 they have special protein channels that allow penicillin to enter the cell and halt the cell cycle.
d.
 they are smaller than gram-negative bacteria and, thus, easily take up penicillin by diffusion.
e.
 they contain prophages that negatively interact with penicillin.
 45.
Some bacteria avoid a host’s immune system by means of:
a.
 efficient use of their flagella.
b.
 ameboid motion.
c.
 their capsule.
d.
 changing their cell wall structure.
e.
 eliminating the use of a membrane.
 46.
Bacteria:
a.
 are incapable of locomotion.
b.
 move by means of pili
c.
 move by means of cilia.
d.
 move by means of a rotating flagella.
e.
 move by means of a whiplike flagella.
 47.
Small circles of DNA called ______________ exist in addition to the bacterial chromosome.
a.
 capsids
b.
 plasmids
c.
 chromatids
d.
 pili
e.
 centromeres
 48.
Small hairlike structures on the surface of bacteria are called:
a.
 capsids.
b.
 pili.
c.
 chromatids.
d.
 plasmids.
e.
 virons.
 49.
Plasmids of bacteria often have genes involved in:
a.
 reproduction.
b.
 motility.
c.
 viral resistance.
d.
 antibiotic resistance.
e.
 photosynthesis.
 50.
Pili are involved in adhesion of bacterial cells to a substrate or host, or in transmission of __________ between bacteria.
a.
 ribosomes
b.
 cytoplasm
c.
 vectors
d.
 RNA
e.
 DNA

 
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PCC Biochemistry

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PCC Biochemistry
 

True/False
Indicate whether the statement is true or false. Write  + for true and  0 for false.
 1.
Atoms have a positive charge.
 2.
An element is made up of more than one kind of atom.
 3.
Hydrogen and oxygen atoms have an equal number of electrons.
 4.
A molecule is an atom that has gained or lost an electron.
 5.
An atom that gains or loses one or more electrons is called an ion.
 6.
An atom with more electrons than protons has a positive charge.
 7.
Ionic bonds form between two negatively charged particles.
 8.
A covalent bond forms between two atoms that share electrons to form a molecule.
 9.
Adhesion is an attraction between different substances.
 10.
The ability of water to retain heat helps cells maintain homeostasis.
 11.
Nonpolar molecules dissolve well in water.
 12.
Water molecules attract nonpolar molecules such as oil.
 13.
Organic compounds contain carbon atoms that are covalently bonded to other elements—typically hydrogen, oxygen, and other carbon atoms.
 14.
A nucleotide has four parts.
 15.
RNA is made up of a double strand of nucleotides.
 16.
DNA stores hereditary information that can be used to make proteins.
 17.
When cells break down food, the energy from the food is temporarily stored as ATP.
 18.
The amount of energy needed to cause a chemical reaction to start is called activation energy.
 19.
Without enzymes, chemical reactions necessary for life would not occur at a rate sufficient to sustain life.
 20.
Enzymes speed up a chemical reaction by increasing the activation energy of the reaction.
 21.
When an enzyme binds with its substrate, the activation energy needed for the chemical reaction to occur is increased.
 22.
Chemical reactions that occur in cells are called biochemical reactions.
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 23.
Atoms are composed of
a.
 protons.
c.
 electrons.
b.
 neutrons.
d.
 All of the above
 24.
The electrons of an atom
a.
 are found in the nucleus along with the protons.
b.
 occupy the space surrounding the nucleus.
c.
 have a positive charge.
d.
 are attached to the positive charge of neutrons.
 25.
The smallest particle of matter that can retain the chemical properties of carbon is a(n)
a.
 carbon molecule.
c.
 carbon atom.
b.
 carbon macromolecule.
d.
 element.
 26.
A substance that is composed of only one type of atom is called a(n)
a.
 nucleus.
c.
 element.
b.
 cell.
d.
 molecule.
 27.
All matter is composed of
a.
 cells.
c.
 atoms.
b.
 molecules.
d.
 carbon.
 28.
A molecule that has a partial positive charge on one side and a partial negative charge on the other side is called a
a.
 nonpolar molecule.
c.
 charged molecule.
b.
 polar molecule.
d.
 bipolar molecule.
 29.
A chemical formula shows the
a.
 kinds of bonds found in the molecule.
b.
 kinds of bonds found in the compound.
c.
 kinds of elements found in the compound.
d.
 arrangement of the elements found in the compound.
 30.
Ionic bonds form between molecules that have
a.
 opposite charges.
c.
 no charges.
b.
 the same charge.
d.
 neutral charges.
 31.
The bond formed when two atoms share a pair of electrons is called a(n)
a.
 hydrogen bond.
c.
 covalent bond.
b.
 ionic bond.
d.
 water bond.
 32.
Sharing of electrons in the outer energy levels of two atoms
a.
 results in ion formation.
b.
 occurs in covalent bonds.
c.
 only occurs if both are atoms of the same element.
d.
 is found only among carbon atoms.
 33.
Water is important to life because it
a.
 surrounds all cells.
b.
 is found inside cells.
c.
 influences the shape of the cell membrane.
d.
 All of the above
 34.
Nonpolar molecules have
a.
 no negative or positive poles.
c.
 only a negative pole.
b.
 both negative and positive poles.
d.
 only a positive pole.
 35.
When placed in the same container, oil and water do not mix because
a.
 they are both polar.
c.
 they are both nonpolar.
b.
 water is polar and oil is nonpolar.
d.
 water is nonpolar and oil is polar.
 36.
Due to the polarity of water, compounds that dissolve best in water contain
a.
 nonpolar bonds.
c.
 polar bonds.
b.
 ionic bonds.
d.
 Both (b) and (c)
 37.
Water is a polar molecule because
a.
 it contains two hydrogen atoms for each oxygen atom.
b.
 it has a charge.
c.
 different parts of the molecule have slightly different charges.
d.
 it does not have a charge.
 38.
Acidic solutions have a pH that is
a.
 less than 7.
c.
 a negative number.
b.
 between 7 and 14.
d.
 more than 7.
 39.
Hydrogen ions, H+, react with hydroxide ions, OH-, to form
a.
 water.
c.
 a base.
b.
 an acid.
d.
 None of the above
 40.
Which of the following is not an organic macromolecule?
a.
 carbohydrate
c.
 lipid
b.
 ice
d.
 nucleic acid
 41.
All organic compounds contain the element
a.
 carbon.
c.
 calcium.
b.
 nitrogen.
d.
 sodium.
 42.
Which of the following organic molecules are classified as carbohydrates?
a.
 amino acids
c.
 nucleotides
b.
 fatty acids
d.
 sugars
 43.
Polysaccharides are
a.
 carbohydrates.
c.
 proteins.
b.
 lipids.
d.
 unsaturated fats.
 44.
Lipids are
a.
 polar molecules.
c.
 water soluble.
b.
 similar to water molecules.
d.
 nonpolar molecules.
 45.
Which of the following organic molecules are most closely related to proteins?
a.
 amino acids
c.
 nucleotides
b.
 fatty acids
d.
 sugars
 46.
Long chains of amino acids are found in
a.
 carbohydrates.
c.
 proteins.
b.
 lipids.
d.
 sugars.
 47.
All of the following are examples of lipids except
a.
 saturated fats.
c.
 cholesterol.
b.
 starch.
d.
 earwax.
 48.
Lipids are soluble in
a.
 water.
c.
 oil.
b.
 salt water.
d.
 All of the above
 49.
Which organic molecules below are most closely related to lipids?
a.
 amino acids
c.
 nucleotides
b.
 fatty acids
d.
 sugars
 50.
Which of the following organic molecules are most closely related to nucleic acids?
a.
 amino acids
c.
 nucleotides
b.
 fatty acids
d.
 sugars
 51.
Which of the following is a carbohydrate?
a.
 DNA
c.
 wax
b.
 insulin
d.
 sucrose
 52.
Carbohydrates and lipids have many carbon-hydrogen bonds; therefore, they both
a.
 store energy in these bonds.
c.
 dissolve only in vinegar.
b.
 are easily dissolved in water.
d.
 exist only in cells of plants.
nar001-1.jpg
nar001-2.jpg
Molecule A
Molecule B
 53.
Refer to the illustration above. Molecules like Molecule B are found in
a.
 carbohydrates.
c.
 nucleic acids.
b.
 lipids.
d.
 proteins.
 54.
Liquid fats called oils contain
a.
 mostly unsaturated fatty acids.
c.
 many glucose molecules.
b.
 mostly saturated fatty acids.
d.
 amino acids.
 55.
Animals store glucose in the form of
a.
 cellulose.
c.
 wax.
b.
 glycogen.
d.
 lipids.
 56.
The shape of a protein is primarily determined by
a.
 the type and sequence of its amino acids.
b.
 its size.
c.
 its cell location.
d.
 None of the above
 57.
The two types of nucleic acids are
a.
 chlorophyll and retinal.
c.
 lipids and sugars.
b.
 DNA and RNA.
d.
 glucose and glycogen.
 58.
DNA stores
a.
 fat.
c.
 protein.
b.
 carbohydrates.
d.
 heredity information.
 59.
The two strands of a DNA molecule are held together by
a.
 ionic bonds.
c.
 hydrogen bonds.
b.
 covalent bonds.
d.
 None of the above
 60.
A molecule shaped like a spiral staircase (double helix) is typical of
a.
 deoxyribonucleic acid.
c.
 lipids.
b.
 ribonucleic acid.
d.
 carbohydrates.
 61.
ATP (adenosine triphosphate) stores energy for cells to use in the bonds between its
a.
 amino acids.
c.
 nucleotides.
b.
 carbon atoms.
d.
 phosphates.
nar002-1.jpg
 62.
Refer to the illustration above. Which graph illustrates what happens during an energy-releasing reaction?
a.
 Graph A
b.
 Graph B
c.
 both graphs because they each show a different stage of an energy releasing reaction
d.
 None of the above
 63.
Refer to the illustration above. Which graph illustrates a reaction during which energy is released?
a.
 Graph A
b.
 Graph B
c.
 both graphs because all chemical reactions release energy
d.
 None of the above
nar003-1.jpg
 64.
Refer to the illustration above. Which of the following statements regarding the graph is true?
a.
 Reaction 2 occurs faster than Reaction 3 because Reaction 2 requires more energy than Reaction 3.
b.
 The difference between the graphs shown for Reaction 2 and Reaction 3 is because of a difference in the activation energy of these reactions.
c.
 Reactant A contains more energy at the beginning of the reaction than product C has after the reaction.
d.
 All of the above
 65.
Refer to the illustration above. Reaction 3 in the graph
a.
 probably occurred in the presence of a catalyst.
b.
 requires more activation energy than Reaction 2.
c.
 is the same as Reaction 1, but faster.
d.
 is slower than Reaction 2.
 66.
The molecule on which an enzyme acts is called a(n)
a.
 active site.
c.
 organic molecule.
b.
 inactive site.
d.
 substrate.
 67.
An enzyme
a.
 is not used up when catalyzing a reaction.
b.
 lowers the activation energy of a reaction.
c.
 bonds with a substrate molecule at the enzyme’s active site.
d.
 All of the above
 68.
Which of the following conditions affects the function of enzymes?
a.
 pH
c.
 enzyme concentration
b.
 heat
d.
 All of the above
 69.
Reducing activation energy
a.
 is a violation of the laws of nature.
b.
 requires higher temperatures than those found within cells.
c.
 occurs only when reactants are quickly added to the reaction mixture.
d.
 is accomplished by the action of catalysts on reactants.
 70.
Enzymes
a.
 are able to heat up molecules so that they can react.
b.
 always provide carbon dioxide for chemical reactions.
c.
 are biological catalysts.
d.
 absorb excess heat so that reactions occur at low temperatures.
 71.
A cell contains
a.
 thousands of different kinds of enzymes, each promoting a different chemical reaction.
b.
 one kind of enzyme that promotes thousands of different chemical reactions.
c.
 approximately 100 kinds of enzymes, each promoting a different chemical reaction.
d.
 one enzyme that promotes photosynthesis and one enzyme that promotes cellular respiration.
 72.
Amylase is a digestive enzyme that breaks down starch into
a.
 amino acids.
c.
 glycogen.
b.
 glucose.
d.
 cellulose.
 73.
The digestive enzyme pepsin works with hydrochloric acid to break down proteins in the stomach. Pepsin probably works best at a pH of
a.
 11.
c.
 3.
b.
 7.
d.
 Both (b) and (c).

 
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PCC Cell Structure and Function 2011

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PCC Cell Structure and Function 2011
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 1.
The smallest units of life in all living things are
a.
 cells.
c.
 cytoplasm.
b.
 mitochondria.
d.
 Golgi apparatus.
 2.
When the volume of a cell increases, its surface area
a.
 increases at the same rate.
b.
 remains the same.
c.
 increases at a faster rate.
d.
 increases at a slower rate.
 3.
Surface area is an important factor in limiting cell growth because
a.
 the cell can burst if the membrane becomes too large.
b.
 materials cannot enter the cell if the surface is too large.
c.
 the cell may become too large to take in enough food and to remove enough wastes.
d.
 waste products cannot leave the cell if the cell is too small.
 4.
The size to which a cell can grow is limited by its
a.
 location.
c.
 function.
b.
 structure.
d.
 surface area.
 5.
A cell that can change its shape would be well suited for
a.
 receiving and transmitting nerve impulses.
b.
 covering the body surface.
c.
 moving to different tissues through narrow openings.
d.
 All of the above
 6.
One difference between prokaryotes and eukaryotes is that
a.
 nucleic acids are found only in prokaryotes.
b.
 mitochondria are found in larger quantities in eukaryotes.
c.
 the Golgi apparatus is found only in prokaryotes.
d.
 prokaryotes have no nuclear membrane.
 7.
Which of the following is characteristic of prokaryotes?
a.
 They have a nucleus.
b.
 They existed on Earth before eukaryotes.
c.
 The organelles in their cytoplasm are surrounded by membranes.
d.
 None of the above
 8.
Which of the following is an example of a prokaryotic cell?
a.
 an amoeba
c.
 a bacterium
b.
 a virus
d.
 a liver cell
 9.
Only eukaryotic cells have
a.
 DNA.
c.
 ribosomes.
b.
 membrane-bound organelles.
d.
 cytoplasm.
 10.
Studying a picture of a cell taken with an electron microscope, you find that the cell has no nucleus and no mitochondria, but it does have a plasma membrane and a cell wall. You conclude that the cell is probably from a(n)
a.
 animal.
c.
 prokaryote.
b.
 plant.
d.
 extinct organism.
 11.
Plasma membranes
a.
 are part of only a small number of cells.
b.
 contain genes.
c.
 are made of DNA.
d.
 are thin coverings that surround cells.
 12.
The structure that regulates what enters and leaves the cell is called the
a.
 nucleus.
c.
 nuclear membrane.
b.
 cell wall.
d.
 plasma membrane.
 13.
The plasma membrane
a.
 encloses the contents of a cell.
b.
 allows material to enter and leave the cell.
c.
 is selectively permeable.
d.
 All of the above
 14.
A structure within a cell that performs a specific function is called a(n)
a.
 organelle.
c.
 tissue.
b.
 organ tissue.
d.
 biocenter.
 15.
A particularly active cell might contain large numbers of
a.
 chromosomes.
c.
 mitochondria.
b.
 vacuoles.
d.
 walls.
 16.
The Golgi apparatus is an organelle that
a.
 receives proteins and lipids from the endoplasmic reticulum.
b.
 labels the molecules made in the endoplasmic reticulum with tags that specify their destination.
c.
 releases molecules in vesicles.
d.
 All of the above
 17.
One important organelle that helps maintain homeostasis by moving supplies from one part of the cell to the other is the
a.
 endoplasmic reticulum.
c.
 nucleus.
b.
 mitochondrion.
d.
 cytoplasm.
 18.
In which of the following organelles is a cell’s ATP produced?
a.
 mitochondrion
c.
 Golgi apparatus
b.
 endoplasmic reticulum
d.
 lysosome
 19.
Numerous hairlike organelles that protrude from the surface of a cell and are packed in tight rows are called
a.
 flagella.
c.
 actin filaments.
b.
 microtubules.
d.
 cilia.
 20.
Proteins are made on the
a.
 mitochondria.
c.
 nucleus.
b.
 ribosomes.
d.
 plasma membrane.
 21.
The packaging and distribution center of the cell is the
a.
 nucleus.
c.
 central vacuole.
b.
 Golgi apparatus.
d.
 nuclear envelope.
 22.
The double membrane surrounding the nucleus is called the
a.
 nucleolus.
c.
 nucleoplasm.
b.
 nuclear wall.
d.
 nuclear envelope.
 23.
All cells have
a.
 a covering called a plasma membrane that surrounds the cell and controls what information and materials enter and leave it.
b.
 an internal fluid that gives shape to the cell and supports the other things within it.
c.
 either a central zone or a nucleus that contains the cell’s genes.
d.
 All of the above
 24.
cell : plasma membrane ::
a.
 nucleus : chromosome
b.
 nucleus : nuclear envelope
c.
 chromosome : DNA
d.
 cell : DNA
nar001-1.jpg
 25.
Refer to the illustration above. Which structure immediately identifies this cell as a eukaryote?
a.
 structure 1
c.
 structure 3
b.
 structure 2
d.
 structure 4
 26.
Refer to the illustration above. The cell uses structure 3
a.
 to transport material from one part of the cell to another.
b.
 to package proteins so they can be stored by the cell.
c.
 as a receptor.
d.
 to transfer energy from organic molecules to ATP.
 27.
Refer to the illustration above. Structure 1 is
a.
 the endoplasmic reticulum.
b.
 a Golgi apparatus.
c.
 a mitochondrion.
d.
 the nucleus.
 28.
Refer to the illustration above. This cell’s chromosomes are found in
a.
 structure 1.
c.
 structure 3.
b.
 structure 2.
d.
 structure 5.
 29.
Refer to the illustration above. The cell shown is probably an animal cell because
a.
 it has mitochondria.
b.
 it does not have a cell wall.
c.
 it has a plasma membrane.
d.
 it does not have a nucleus.
 30.
All of the following are found in both plant and animal cells, except
a.
 a cell wall.
c.
 mitochondria.
b.
 a plasma membrane.
d.
 the endoplasmic reticulum.
 31.
How are chloroplasts like mitochondria?
a.
 They can both use energy from sunlight.
b.
 They look alike.
c.
 They both contain DNA.
d.
 They are both found in animal cells.
 32.
The organelles associated with photosynthesis are the
a.
 mitochondria.
c.
 Golgi apparatus.
b.
 chloroplasts.
d.
 vacuoles.
 33.
The organelles in plant cells that contain a green pigment are the
a.
 mitochondria.
c.
 chloroplasts.
b.
 bilayer lipids.
d.
 Golgi apparatus.
 34.
Plant cells have a large membrane-bound space in which water, waste products, and nutrients are stored. This place is known as a
a.
 mitochondrion.
c.
 Golgi apparatus.
b.
 chloroplast.
d.
 central vacuole.
 35.
Which of the following pairs contains unrelated items?
a.
 eukaryote–amoeba
c.
 cell wall–animal cell
b.
 ribosomes–protein
d.
 mitochondria–energy
 36.
Plant cells
a.
 do not contain mitochondria.
b.
 have a cell wall instead of a plasma membrane.
c.
 have a large central vacuole instead of a Golgi apparatus.
d.
 have chloroplasts and a cell wall.
 37.
Which of the following is the correct order of organization of structures in living things, from simplest to most complex?
a.
 organ systems, organs, tissues, cells
b.
 tissues, cells, organs, organ systems
c.
 cells, tissues, organ systems, organs
d.
 cells, tissues, organs, organ systems
 38.
As a result of diffusion, the concentration of many types of substances
a.
 always remains greater inside a membrane.
b.
 eventually becomes balanced on both sides of a membrane.
c.
 always remains greater on the outside of a membrane.
d.
 becomes imbalanced on both sides of a membrane.
nar002-1.jpg
 39.
Refer to the illustration above. In which direction are water molecules in this system most likely to diffuse?
a.
 from 1 to 2
c.
 from 4 to 3
b.
 from 2 to 4
d.
 from 3 to 1
 40.
The dispersal of ink in a beaker of water is an example of
a.
 diffusion.
c.
 active transport.
b.
 osmosis.
d.
 endocytosis.
 41.
Sugar molecules can enter cells through the process of
a.
 exocytosis.
c.
 osmosis.
b.
 facilitated diffusion.
d.
 ion pumps.
 42.
Channels utilizing facilitated diffusion
a.
 work in two directions.
b.
 require an electrical signal to function.
c.
 Both a and b
d.
 None of the above
 43.
Which of the following is not characteristic of facilitated diffusion?
a.
 It requires a carrier protein.
b.
 It moves substances against a concentration gradient.
c.
 It requires no energy input.
d.
 It involves a change in the shape of its carrier.
 44.
Which of the following does not expend energy?
a.
 diffusion
c.
 active transport
b.
 endocytosis
d.
 a sodium-potassium pump
 45.
Which of the following enters a cell by active transport?
a.
 glucose
c.
 lactose
b.
 water
d.
 potassium ion
 46.
The process by which water passes into or out of a cell is called
a.
 solubility.
c.
 selective transport.
b.
 osmosis.
d.
 endocytosis.
 47.
The sodium-potassium pump usually pumps
a.
 potassium out of the cell.
b.
 sodium into the cell.
c.
 potassium into the cell.
d.
 only a potassium and sugar molecule together.
 48.
Ridding the cell of material by discharging it from sacs at the cell surface is called
a.
 pinocytosis.
c.
 exocytosis.
b.
 phagocytosis.
d.
 endocytosis.
 49.
Molecules that are too large to be moved across a cell membrane can be removed from the cell by
a.
 diffusion.
c.
 lipid carriers.
b.
 exocytosis.
d.
 osmosis.
 50.
Placing a plant into a hypertonic environment will
a.
 cause turgor pressure to increase.
b.
 cause the plant to take in water.
c.
 have no effect.
d.
 cause turgor pressure to decrease.

 
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Mollusks

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Mollusks

 

 

True/False
Indicate whether the sentence or statement is true or false.
1.
Mollusks must eat constantly because the functioning of their nephridia causes the disposal of useful molecules as well as of waste products.
2.
Unlike arthropods, mollusks are unsegmented; instead, they are divided into three regions.
3.
Mollusks have four distinct body parts: a foot, a head, a visceral mass, and a tail.
4.
In terrestrial snails, the mantle cavity functions as a simple lung.
5.
Most bivalves have separate sexes, but some are hermaphroditic.
6.
Due to the presence of a shell, all gastropods are capable of living on land for at least a portion of their lives.
7.
Since cephalopods have tentacles, they have no need for a radula.
 

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
8.
All of the following are characteristics of mollusks except that they have
a.
a pseudocoelomate body plan.
c.
a complete digestive tract.
b.
bilateral symmetry.
d.
an open circulatory system.
9.
The cilia of a trochophore larva
a.
allow attachment to the ocean bottom.
b.
create currents for drawing in food.
c.
cover the entire larval body.
d.
are necessary for reproduction.
10.
Trochophore larvae
a.
are found in molluscan life cycles.
b.
possess a belt of cilia around their bodies.
c.
occur in annelid life cycles.
d.
All of the above
11.
A characteristic structure found in many mollusks is the radula, which is involved in
a.
jet propulsion.
c.
eating.
b.
opening and closing of the shells.
d.
reproduction.
12.
All of the following are classes of the phylum Mollusca except
a.
bivalves.
c.
gastropods.
b.
cephalopods.
d.
pseudopods.
13.
The only mollusks that have a closed circulatory system are
a.
bivalves.
c.
chitons.
b.
cephalopods.
d.
gastropods.
      mollusks_files/i0160000.jpg
14.
Refer to the illustration above. Which two organisms in the diagrams possess mantles?
a.
Organisms “A” and “C”
c.
Organisms “A” and “D”
b.
Organisms “B” and “C”
d.
Organisms “B” and “D”
15.
“Jet propulsion” is the usual means of locomotion in water for
a.
arthropods.
c.
cephalopods.
b.
echinoderms.
d.
annelids.
      mollusks_files/i0190000.jpg
16.
Refer to the illustration above. The organism shown in this diagram is a
a.
bivalve.
c.
chiton.
b.
cephalopod.
d.
gastropod.
17.
Refer to the illustration above. This organism possesses a(n)
a.
simple lung.
c.
internal beak.
b.
closed circulatory system.
d.
open circulatory system.
18.
Refer to the illustration above. Movement of this organism is dependent upon the structure labeled
a.
“1.”
c.
“3.”
b.
“2.”
d.
None of the above
19.
Shells of mollusks
a.
may consist of one or more pieces.
c.
allow for the attachment of muscles.
b.
provide protection.
d.
All of the above
20.
Adductor muscles are responsible for
a.
moving the valves of bivalves.
c.
pumping the hearts of mollusks.
b.
extending the feet of mollusks.
d.
fanning the gills of aquatic mollusks.

 
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Nucleic Acids

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Nucleic Acids

 

 

Modified True/False
Indicate whether the statement is true or false.  If false, change the identified word or phrase to make the statement true.
 1.
It has been discovered that the genetic material is protein. _________________________
 2.
Hershey and Chase were the first two scientists to prove that genetic material is composed of proteins. _________________________
 3.
The five-carbon sugar in DNA nucleotides is called ribose. _________________________
 4.
After years of research, the structure of the DNA molecule is now known to be a double helix. _________________________
 5.
Franklin’s X-ray diffraction images suggested that the DNA molecule resembled a tightly coiled spring, a shape called a helix. _________________________
 6.
In all living things, DNA replication must occur after cell division. _________________________
 7.
Before a DNA molecule can replicate itself, it must coil up. _________________________
 8.
Helicases unwind the double helix of DNA by breaking the nitrogen bonds that link the base pairs. _________________________
 9.
Errors in nucleotide sequence that occur during replication cannot be corrected. _________________________
 10.
RNA molecules contain the five-carbon sugar ribose. _________________________
 11.
During transcription, the information on a DNA molecule is “rewritten” into an mRNA molecule. _________________________
 12.
When a tRNA anticodon binds to an mRNA codon, the amino acid detaches from the tRNA molecule and bonds to the end of a growing protein chain. _________________________
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 13.
Griffith’s transformation experiments
a.
 changed proteins into DNA.
b.
 caused harmless bacteria to become deadly.
c.
 resulted in DNA molecules becoming proteins.
d.
 were designed to show the effect of heat on bacteria.
 14.
Griffith’s experiments showed that
a.
 dead bacteria could be brought back to life.
b.
 harmful bacteria were hardier than harmless bacteria.
c.
 heat caused the harmful and harmless varieties of bacteria to fuse.
d.
 genetic material could be transferred between dead bacteria and living bacteria.
 15.
Avery’s experiments showed that transformation
a.
 is prevented by protein-destroying enzymes.
b.
 is prevented by DNA-destroying enzymes.
c.
 causes protein to become DNA.
d.
 is caused by a protein.
 16.
Avery and his research team concluded that
a.
 RNA was the genetic material.
b.
 protein bases were the genetic material.
c.
 DNA and RNA were found in the human nucleus.
d.
 DNA was responsible for transformation.
 17.
Using radioactive tracers to determine the interactions of bacteriophages and their host bacteria, Hershey and Chase demonstrated without question that
a.
 genes are composed of protein molecules.
b.
 DNA and proteins are actually the same molecules located in different parts of cells.
c.
 bacteria inject their DNA into the cytoplasm of bacteriophages.
d.
 DNA is the molecule that stores genetic information in cells.
 18.
All of the following are true of the viruses Hershey and Chase used in their study except
a.
 they consisted of DNA surrounded by a protein coat.
b.
 they injected their DNA into cells.
c.
 they destroyed the DNA of the infected bacteria.
d.
 they caused infected bacteria to make many new viruses.
 19.
The scientist who worked with Martha Chase to prove that genetic material is composed of DNA was
a.
 Alfred Hershey.
c.
 Francis Crick.
b.
 Oswald Avery.
d.
 Rosalind Franklin.
 20.
Molecules of DNA are composed of long chains of
a.
 amino acids.
c.
 monosaccharides.
b.
 fatty acids.
d.
 nucleotides.
 21.
Which of the following is not part of a molecule of DNA?
a.
 deoxyribose
c.
 phosphate
b.
 nitrogen base
d.
 ribose
 22.
A nucleotide consists of
a.
 a sugar, a protein, and adenine.
b.
 a sugar, an amino acid, and starch.
c.
 a sugar, a phosphate group, and a nitrogen base.
d.
 a starch, a phosphate group, and a nitrogen base.
 23.
The part of the molecule for which DNA is named is the
a.
 phosphate group.
c.
 nitrogen base.
b.
 sugar.
d.
 hydrogen bonds.
 24.
Purines and pyrimidines are
a.
 nitrogen bases found in amino acids.
b.
 able to replace phosphate groups from defective DNA.
c.
 names of specific types of DNA molecules.
d.
 classification groups of nitrogen bases.
 25.
Of the four nitrogen bases in DNA, which two are purines and which two are pyrimidines?
a.
 purines: adenine, thymine; pyrimidines: uracil, cytosine
b.
 purines: adenine, thymine; pyrimidines: guanine, cytosine
c.
 purines: adenine, guanine; pyrimidines: thymine, cytosine
d.
 purines: uracil, thymine; pyrimidines: guanine, cytosine
 26.
The amount of guanine in an organism always equals the amount of
a.
 protein.
c.
 adenine.
b.
 thymine.
d.
 cytosine.
 27.
adenine : thymine ::
a.
 protein : DNA
c.
 guanine : cytosine
b.
 Watson : Crick
d.
 guanine : thymine
 28.
Watson and Crick built models that demonstrated that
a.
 DNA and RNA have the same structure.
b.
 DNA is made of two strands that twist into a double helix.
c.
 guanine forms hydrogen bonds with adenine.
d.
 thymine forms hydrogen bonds with cytosine.
 29.
The scientists credited with establishing the structure of DNA are
a.
 Avery and Chargaff.
c.
 Mendel and Griffith.
b.
 Hershey and Chase.
d.
 Watson and Crick.
 30.
X-ray diffraction photographs by Wilkins and Franklin suggested that
a.
 DNA and RNA are the same molecules.
b.
 DNA is composed of either purines or pyrimidines, but not both.
c.
 DNA molecules are arranged as a tightly coiled helix.
d.
 DNA and proteins have the same basic structure.
 31.
During DNA replication, a complementary strand of DNA is made from each original DNA strand. Thus, if a portion of the original strand is CCTAGCT, then the new strand will be
a.
 TTGCATG.
c.
 CCTAGCT.
b.
 AAGTATC.
d.
 GGATCGA.
 32.
Which of the following is not true about DNA replication?
a.
 It must occur before a cell can divide.
b.
 Two complementary strands are duplicated.
c.
 The double strand unwinds and unzips while it is being duplicated.
d.
 The new DNA molecule has two newly-made strands.
 33.
The attachment of nucleotides to form a complementary strand of DNA during replication
a.
 is accomplished by DNA polymerase.
b.
 is accomplished only in the presence of tRNA.
c.
 prevents separation of complementary strands of RNA.
d.
 is the responsibility of the proofreading enzymes.
 34.
The enzymes responsible for adding nucleotides to the exposed DNA bases during replication are
a.
 replicases.
c.
 helicases.
b.
 DNA polymerases.
d.
 template enzymes.
 35.
The enzymes that unwind DNA during replication are called
a.
 double helixes.
c.
 forks.
b.
 DNA helicases.
d.
 phages.
 36.
All of the following are true about DNA replication in prokaryotic cells except
a.
 replication begins at many sites along the DNA.
b.
 replication begins at one site along the DNA loop.
c.
 replication occurs in two opposite directions.
d.
 there are two replication forks.
 37.
Transcription, which is a stage of gene expression, is the process by which genetic information encoded in DNA is transferred to a(n)
a.
 RNA molecule.
c.
 uracil molecule.
b.
 DNA molecule.
d.
 tRNA molecule.
 38.
RNA differs from DNA in that RNA
a.
 is double-stranded.
c.
 contains the nitrogen base uracil.
b.
 contains deoxyribose.
d.
 does not contain adenine.
 39.
RNA is chemically similar to DNA except that the sugar in RNA has an additional
a.
 oxygen atom.
c.
 nitrogen base.
b.
 phosphate group.
d.
 carbon atom.
 40.
In RNA molecules, adenine is complementary to
a.
 cytosine.
c.
 thymine.
b.
 guanine.
d.
 uracil.
 41.
Each of the following is a type of RNA except
a.
 carrier RNA.
c.
 ribosomal RNA.
b.
 messenger RNA.
d.
 transfer RNA.
 42.
During transcription,
a.
 proteins are synthesized.
c.
 RNA is produced.
b.
 DNA is replicated.
d.
 translation occurs.
 43.
During transcription, the genetic information for making a protein is “rewritten” as a molecule of
a.
 messenger RNA.
c.
 transfer RNA.
b.
 ribosomal RNA.
d.
 translation RNA.
 44.
Transcription begins when RNA polymerase
a.
 attaches to a ribosome.
b.
 unwinds a strand of DNA.
c.
 binds to a strand of RNA.
d.
 attaches to the promoter sequence of a gene.
mRNA: CUCAAGUGCUUC

nar001-1.jpg
 45.
Refer to the illustration above. What is the portion of the protein molecule coded for by a piece of mRNA with the sequence CUCAAGUGCUUC?
a.
 Ser—Tyr—Arg—Gly
c.
 Leu—Lys—Cys—Phe
b.
 Val—Asp—Pro—His
d.
 Pro—Glu—Leu—Val
 46.
Refer to the illustration above. The anticodons for the codons in the mRNA with the sequence CUCAAGUGCUUC are
a.
 GAG—UUC—ACG—AAG.
c.
 CUC—GAA—CGU—CUU.
b.
 GAG—TTC—ACG—AAG.
d.
 CUU—CGU—GAA—CUC.
 47.
Refer to the illustration above. Which of the following would represent the strand of DNA from which the mRNA strand CUCAAGUGCUUC was made?
a.
 CUCAAGUGCUUC
c.
 GAGTTCACGAAG
b.
 GAGUUCACGAAG
d.
 AGACCTGTAGGA
mRNA codons amino acid
UAU, UAC tyrosine
CCU, CCC, CCA, CCG proline
GAU, GAC aspartic acid
AUU, AUC, AUA isoleucine
UGU, UGC cysteine
 48.
Refer to the illustration above. Suppose that you are given a protein containing the following sequence of amino acids: tyrosine, proline, aspartic acid, isoleucine, and cysteine. Use the portion of the genetic code given to determine which of the following contains a DNA sequence that codes for this amino acid sequence.
a.
 AUGGGUCUAUAUACG
c.
 GCAAACTCGCGCGTA
b.
 ATGGGTCTATATACG
d.
 ATAGGGCTTTAAACA
 49.
The function of rRNA is to
a.
 synthesize DNA.
c.
 form ribosomes.
b.
 synthesize mRNA.
d.
 transfer amino acids to ribosomes.
 50.
At the very beginning of translation, the first tRNA molecule
a.
 binds to the mRNA’s anticodon.
b.
 attaches directly to the DNA codon.
c.
 connects an amino acid to its anticodon.
d.
 binds to the mRNA’s start codon.
 51.
Transfer RNA
a.
 carries an amino acid to its correct codon.
b.
 synthesizes amino acids as they are needed.
c.
 produces codons to match the correct anticodons.
d.
 converts DNA into mRNA.
 52.
Which of the following does not affect the final outcome of gene expression?
a.
 the environment of the cells
b.
 the number of amino acids in the protein being produced
c.
 the presence of other cells
d.
 the timing of gene expression
 

Completion
Complete each statement.
 53.
Griffith’s experiment showed that live bacteria without capsules acquired the ability to make capsules from dead bacteria with capsules in a process Griffith called ____________________.
 54.
Avery’s prevention of transformation using DNA-destroying enzymes provided evidence that ____________________ molecules function as the hereditary material.
 55.
A DNA subunit composed of a phosphate group, a five-carbon sugar, and a nitrogen-containing base is called a(n) ____________________.
 56.
The name of the five-carbon sugar that makes up a part of the backbone of molecules of DNA is ____________________.
 57.
Due to the strict pairing of nitrogen bases in DNA molecules, the two strands are said to be ____________________ to each other.
 58.
Watson and Crick determined that DNA molecules have the shape of a(n) ____________________ ____________________.
 59.
Chargaff’s observations established the ____________________ rules, which describe the specific pairing between bases on DNA strands.
 60.
Watson and Crick used the X-ray diffraction photographs of ____________________ and ____________________ to build their model of DNA.
 61.
The process by which DNA copies itself is called ____________________.
 62.
Enzymes called ____________________ are responsible for unwinding the DNA double helix by breaking the hydrogen bonds that hold the complementary strands together.
 63.
Errors in nucleotide sequencing are corrected by enzymes called ____________________.
 64.
Transcription and translation are stages in the process of ____________________.
 65.
The second stage of gene expression is called ____________________.
 66.
The nitrogen-containing base that is found only in RNA is ____________________.
 67.
The enzyme responsible for making mRNA is called ____________________.
 68.
Messenger RNA is produced during the process of ____________________.
 69.
The sequence of three nucleotides that code for specific amino acids or stop signals in the synthesis of protein is called a(n) ____________________.
 70.
During translation, amino acids are brought to the ribosomes by molecules of ____________________.
 71.
Nucleotide sequences of tRNA that are complementary to codons on mRNA are called ____________________.
 72.
The information contained in a molecule of messenger RNA is used to make protein during the process of ____________________.

 
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