Author: Biology Junction Team

Transcription and Translation Tool

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Transcription and Translation Tool Converts DNA to RNA to protein.

DNA sequence:
RNA sequence:
 Protein sequence:
DNA (deoxyribonucleic acid)

  • a permanent copy of genetic information.
  • uses “T” instead of “U”
  • no 2′ OH group
  • more stable than RNA
  • lower error frequency during replication than RNA
RNA (ribonucleic acid)

  • messenger RNA (mRNA) is a temporary copy of the gene sequence in which protein is encoded.
Protein

  • consists of amino acids linked by aminoester (“peptide”) bonds.
  • most enzymes and many structural components of cells are made of proteins.

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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Taxonomy Study Guide

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Taxonomy Quiz

 

 

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.
Scientists use taxonomy to determine the evolutionary history of organisms. _________________________
 2.
Taxonomy provides consistent ways to name organisms. _________________________
 3.
Scientific names of organisms consist of two English terms. _________________________
 4.
Two different organisms cannot have the same scientific name. _________________________
 5.
Genus is the basic biological unit in the Linnaean system of classification. _________________________
 6.
A genus is a taxonomic category that contains several families. _________________________
 7.
Under the Linnaean system of classification, organisms are grouped on the basis of similarities in structure. _________________________
 8.
Linnaeus devised eight levels of classification categories for living things. _________________________
 9.
The least inclusive group to which an organism can be assigned is its kingdom. _________________________
 10.
Kingdoms are subgroups of phyla. _________________________
 11.
A species is a larger taxonomic group than a genus. _________________________
 12.
Bird wings and insect wings are examples of analogous structures. _________________________
 13.
Organisms that have similar traits but evolved independently are the result of convergent evolution. _________________________
 14.
Cladistics is used to determine the sequence in which different groups of organisms evolved. _________________________
 15.
In modern systematics, studies of the changes in the skeletons of vertebrates have helped researchers to estimate the time at which each species began to evolve. _________________________
 16.
Comparing the sequence of DNA bases in the genes of several organisms is used to determine the order in which the organisms evolved. _________________________
 17.
All organisms in the kingdom Animalia are multicellular heterotrophs whose cells lack cell walls. _________________________
 18.
Archaea are eukaryotes that are characterized by several unique biochemical characteristics. _________________________
 19.
Traditionally, bacteria have been classified on the basis of their shape, cell wall composition, and metabolism. _________________________
 20.
Most organisms in the kingdoms Plantae and Animalia are multicellular. _________________________
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 21.
Taxonomy is
a.
 the study of life.
b.
 the science of naming and classifying organisms.
c.
 the evolutionary history of a species.
d.
 the sequence in which different groups evolved.
 22.
An advantage of our scientific naming system is that
a.
 common names mean the same in all countries.
b.
 Latin names are easy to pronounce.
c.
 biologists can communicate regardless of their native languages.
d.
 organisms all have the same scientific name.
 23.
All scientific names of organisms must be
a.
 unique and have two Latin words.
b.
 general and use the species name.
c.
 different and repeat the phylum name.
d.
 similar and include the common name.
 24.
Linnaeus’s two-word system for naming organisms is called
a.
 taxonomic evolution.
c.
 Greek polynomials.
b.
 Genus species.
d.
 binomial nomenclature.
 25.
In the Linnaean system of classification, the level that identifies one unique organism is the
a.
 kingdom.
c.
 genus.
b.
 family.
d.
 species.
 26.
The largest division that a group of organisms can belong to is a
a.
 domain.
c.
 genus.
b.
 class.
d.
 kingdom.
 27.
Placement in each level of classification is based on
a.
 specific characteristics.
c.
 shared characteristics.
b.
 general characteristics.
d.
 different characteristics.
 28.
Similar genera are grouped into a(n)
a.
 phylum.
c.
 family.
b.
 class.
d.
 order.
 29.
Analogous structures
a.
 have a common size in organisms.
b.
 perform the same function in organisms.
c.
 have the same structure in organisms.
d.
 evolve from a common ancestor.
 30.
Traditional systematics emphasizes the importance of
a.
 derived characteristics.
c.
 similar characteristics.
b.
 unique characteristics.
d.
 compared characteristics.
 31.
Similar features that evolve through convergent evolution are called
a.
 analogous characters.
c.
 environmental characters.
b.
 homologous characters.
d.
 genetic characters.
 32.
Convergent evolution produces analogous characters in different species as the result of
a.
 similar environments.
c.
 sharing a common ancestor.
b.
 different environments.
d.
 shared derived characters.
 33.
A phylogenetic tree differs from a cladogram in that a phylogenetic tree
a.
 hypothesizes the time at which each group of organisms evolved.
b.
 also indicates the new characteristics that evolved with each group of organisms
c.
 only illustrates hypothesized relationships among groups of organisms.
d.
 predicts the next group of organisms that is expected to evolve.
 34.
Studies of fossils of dinosaurs and birds show that
a.
 feathers may not be an important difference between dinosaurs and birds.
b.
 dinosaurs can be considered to be modern descendents of birds.
c.
 the anatomies of the dinosaurs and birds are unrelated.
d.
 dinosaurs and birds share many analogous characters.
 35.
A model used by biologists to represent evolutionary history among species is called a
a.
 phylogram.
c.
 histogram.
b.
 cladogram.
d.
 parallelogram.
 36.
Derived characters are traits
a.
 that are shared by all species.
b.
 that originated in a common ancestor.
c.
 found in closely related species.
d.
 found in distantly related species.
 37.
During Linnaeus’ time, scientists divided all living organisms into
a.
 five phyla.
c.
 three domains.
b.
 four families.
d.
 two kingdoms.
 38.
Sponges are animals that were once classified as
a.
 bacteria.
c.
 plants.
b.
 fungi.
d.
 protists.
 39.
Which of the following characteristics was used to reclassify sponges?
a.
 body type
c.
 cell walls
b.
 cell type
d.
 nutrition
 40.
The kingdoms Eubacteria and Archaebacteria were once grouped in a kingdom called
a.
 Protista.
c.
 Monera.
b.
 Animalia.
d.
 Plantae.
 41.
Four of the kingdoms include eukaryotes and the other two include
a.
 plants.
c.
 animals.
b.
 fungi.
d.
 prokaryotes.
 42.
Which of the following is not a characteristic used to differentiate kingdoms?
a.
 cell type
c.
 nutrition
b.
 root system
d.
 body type
 43.
Protista is an example of a
a.
 kingdom.
c.
 genus.
b.
 class.
d.
 species.
 44.
Which two kingdoms contain both unicellular and multicellular organisms?
a.
 Archaea and Animalia
c.
 Animalia and Fungi
b.
 Protists and Bacteria
d.
 Protista and Fungi
 45.
One difference between plants and animals is that plants are
a.
 prokaryotic and animals are eukaryotic.
b.
 eukaryotic and animals are prokaryotic.
c.
 autotrophs and animals are heterotrophs.
d.
 heterotrophs and animals are autotrophs.
 

Completion
Complete each statement.
 46.
The current system used for naming organisms was developed by ____________________.
 47.
The two-word system for naming organisms is called _________________________.
 48.
The scientific name of an organism gives biologists a common way of ____________________ regardless of their native languages.
 49.
All names assigned to organisms under the Linnaean system are in the ____________________ language.
 50.
The unique two-word name for a species is its ____________________ name.
 51.
All living things are grouped into one of three ____________________.
 52.
There are ____________________ levels of classification in the modern classification system.
 53.
A kingdom contains many ____________________.
 54.
Classes with similar characteristics are assigned to a(n) ____________________.
 55.
Each level of classification is based on ____________________ shared by all the organisms it contains.
 56.
Homo habilis, Homo erectus, and Homo sapiens all belong to the same ____________________.
 57.
Traditionally, scientists have used differences in appearance and ____________________ to classify organisms.
 58.
Unlike cladistics, traditional systematics places more ____________________ on some traits than on others.
 59.
Analogous structures are found in ____________________ taxa as a result of similar environmental conditions.
 60.
The type of evolution that results in similar characteristics found in different organisms as the result of selection within similar environments is called ____________________ evolution.
 61.
The evolutionary history of a species is called its ____________________.
 62.
Shared derived characters are found in organisms that once shared a(n) ____________________ ancestor.
 63.
A method of analysis that reconstructs phylogenies by inferring relationships based on shared characteristics is called ____________________.
 64.
A model developed by systematists that uses shared derived characters to show the evolutionary history of different organisms is called a(n) ____________________.
 65.
Cladistics is used to determine the ____________________ in which different groups of organisms evolved.
 66.
Animals that appear early on a cladogram do not share as many of the same ____________________ traits as the animals that appear later on the cladogram.
 67.
Modern systematic biologists use the ____________________ rate of DNA mutations like a “molecular clock.”
 68.
Bacteria have strong exterior cell walls made of ____________________.
 69.
An organism made of many cells that are permanently associated and that coordinate their activities is called a(n) ____________________ organism.
 70.
Eukaryotes that are not fungi, plants, or animals are called ____________________.


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Study Guide Cellular Respiration

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Multiple Choice
Identify the choice that best completes the statement or answers the question.
 1.
When cells break down food molecules, energy
a.
 is released all at once.
b.
 is released entirely as body heat into the environment.
c.
 is temporarily stored in ATP molecules.
d.
 causes excitation of electrons in chlorophyll molecules.
 2.
ATP
a.
 contains five phosphate groups.
b.
 is essential for a cell to perform all the tasks necessary for life.
c.
 is found only in bacteria.
d.
 All of the above
 3.
A substance produced during photosynthesis that is used for completion of cellular respiration is
a.
 water.
c.
 NADPH.
b.
 ATP.
d.
 oxygen.
 4.
The process of cellular respiration
a.
 is performed only by organisms that are incapable of photosynthesis.
b.
 breaks down food molecules to release stored energy.
c.
 occurs before plants are able to carry out photosynthesis.
d.
 occurs only in animals.
 5.
cellular respiration : organic compounds ::
a.
 light bulb : glass
c.
 automobile : gasoline
b.
 trunk : clothing
d.
 country : nation
 6.
When glycolysis occurs,
a.
 a molecule of glucose is split.
b.
 two molecules of pyruvic acid are made.
c.
 some ATP is produced.
d.
 All of the above
 7.
The name of the process that takes place when organic compounds are broken down in the absence of oxygen is
a.
 respiration.
c.
 fermentation.
b.
 oxidation.
d.
 All of the above
 8.
When muscles are exercised extensively in the absence of sufficient oxygen,
a.
 a large amount of ATP is formed.
b.
 NADH molecules split.
c.
 lactic acid is produced.
d.
 cellular respiration ceases.
 9.
You have been growing some animal cells in culture. The cells grow well for several weeks, and then their growth slows down. You conduct some tests and determine that there is a lot of lactic acid in the culture fluid. Which of the following is the most likely explanation for the poor growth of the cells?
a.
 There is too much glucose in the culture fluid.
b.
 There is not enough glucose in the culture fluid.
c.
 There is too much oxygen in the culture fluid.
d.
 There is not enough oxygen in the culture fluid.
 10.
If the formation of a standard amount of ATP under certain conditions requires 12 kcal of energy and the complete oxidation of glucose yields 686 kcal of energy, how efficient is glycolysis at extracting energy from glucose?
a.
 1.7%
c.
 7.0%
b.
 3.5%
d.
 35%
 11.
Cellular respiration takes place in two stages:
a.
 glycolysis and fermentation.
b.
 Stage 1 and Stage 2 of photosynthesis.
c.
 glycolysis, then aerobic respiration.
d.
 aerobic respiration, then glycolysis.
 12.
In cellular respiration, a two-carbon molecule combines with a four-carbon molecule to form citric acid as part of
a.
 glycolysis.
b.
 carbon fixation.
c.
 the Krebs cycle.
d.
 the electron transport chain.
 13.
Acetyl coenzyme A
a.
 is formed from the breakdown of pyruvic acid.
b.
 enters the Krebs cycle.
c.
 can be used in synthesis of needed molecules.
d.
 All of the above
 14.
Glycolysis and aerobic respiration are different in that
a.
 glycolysis occurs on the cell membrane, while aerobic respiration occurs in mitochondria.
b.
 glycolysis occurs only in photosynthesis, while aerobic respiration is part of cellular respiration.
c.
 glycolysis occurs in the absence of oxygen, while aerobic respiration requires oxygen.
d.
 There is no difference; these terms are different names for the same process.
 15.
Which of the following is not formed during the Krebs cycle?
a.
 CO2
c.
 NADH
b.
 FADH2
d.
 NADPH
 16.
Which of the following is not part of cellular respiration?
a.
 electron transport
c.
 the Krebs cycle
b.
 glycolysis
d.
 the Calvin cycle
 17.
With oxygen present, the Krebs cycle and the electron transport chain
a.
 provide organisms an alternative to glycolysis.
b.
 produce most of the ATP needed for life.
c.
 break down glucose to produce carbon dioxide, water, and ATP.
d.
 All of the above
 18.
Water is an end product in
a.
 lactic acid formation.
c.
 the Krebs cycle.
b.
 fermentation.
d.
 the electron transport chain.
 19.
Krebs cycle : CO2 ::
a.
 glycolysis : glucose
b.
 acetyl CoA formation : O2
c.
 cellular respiration : O2
d.
 electron transport chain : ATP
 20.
ATP molecules produced during aerobic respiration
a.
 remain in the mitochondria in which they are formed.
b.
 are stored in chloroplasts of the same cell in which they are formed.
c.
 enter the cell’s cytoplasm through the membranes of the mitochondria in which they are formed.
d.
 are distributed by the bloodstream to all cells in the body.
 21.
At the end of the electron transport chain,
a.
 the electrons combine with oxygen and protons to form water.
b.
 the electrons are used in the formation of ethyl alcohol.
c.
 the electrons build up inside the mitochondria and diffuse back to a thylakoid.
d.
 None of the above
C6 H12O6 + 6O2 + ADP + P ® 6CO2 + 6 H2O + MOLECULE A
 22.
The process shown in the equation above begins in the cytoplasm of a cell and ends in the
a.
 cytoplasm.
c.
 endoplasmic reticulum.
b.
 mitochondria.
d.
 lysosome.
 23.
The equation above summarizes the process known as
a.
 photosynthesis.
c.
 cellular respiration.
b.
 fermentation.
d.
 protein breakdown.
 24.
The molecule referred to as “molecule A” in the equation above is
a.
 NADPH.
c.
 NADH.
b.
 ATP.
d.
 ADP.
 25.
When living cells break down molecules, energy is
a.
 stored as ADP.
c.
 released as heat.
b.
 stored as ATP.
d.
 Both b and c
 26.
Which of the following is the best explanation for the presence of both chloroplasts and mitochondria in plant cells?
a.
 In the light, plants are photosynthetic autotrophs. In the dark, they are heterotrophs.
b.
 If plants cannot produce enough ATP in the process of photosynthesis to meet their energy needs, they can produce it in aerobic respiration.
c.
 Sugars are produced in chloroplasts. These sugars can be stored in the plant for later use, converted to other chemicals, or broken down in aerobic respiration to yield ATP for the plant to use to meet its energy needs.
d.
 The leaves and sometimes the stems of plants contain chloroplasts, which produce ATP to meet the energy needs of these plant parts. The roots of plants contain mitochondria, which produce ATP to meet the energy needs of these plant parts.
 27.
In cellular respiration, the most energy is transferred during
a.
 glycolysis.
b.
 lactic acid fermentation.
c.
 the Krebs cycle.
d.
 the electron transport chain
 28.
Electrons are donated to the electron transport chain by
a.
 ATP and NADH.
c.
 ATP and NAD+.
b.
 FADH2 and NADH.
d.
 NAD+ and ATP.
 29.
If the formation of 38 molecules of ATP requires 266 kcal of energy and the complete oxidation of glucose yields 686 kcal of energy, how efficient is cellular respiration at extracting energy from glucose?
a.
 20%
c.
 25%
b.
 39%
d.
 100%
 

Completion
Complete each statement.
 30.
During fermentation, either ethyl alcohol and carbon dioxide or ____________________ is formed.
 31.
Of the maximum possible yield of 38 ATP molecules produced by the complete oxidation of one glucose molecule, ____________________ molecules of ATP are produced during glycolysis.
 32.
The Krebs cycle takes place in the _________________________.
 

Essay
 33.
The relationship between photosynthesis and cellular respiration is usually described as a cycle. Briefly explain. Write your answer in the space below.

 
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