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Ecology Quiz

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Ecology Quiz

 

Test your knowledge of Ecology!

1. A cold biome characterized by permafrost under the surface?
a) Taiga
b) Tundra
c) Deciduous forest
d) Savanna2. An organism that feeds on plants and animals?
a) Carnivore
b) Omnivore
c) Epiphyte
d) Herbivore

3. All of the following are abiotic factors except:
a) Tree
b) Temperature
c) pH
d) Sunlight

4. Corals would be found in which zone:
a) Oceanic
b) Estuary
c) Neritic
d) Benthic

5. Which of the following is not part of the nitrogen cycle:
a) Ammonification
b) Transpiration
c) Nitrification
d) Rhizobacteria

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Echinoderm

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Echinoderm

 

 

True/False
Indicate whether the sentence or statement is true or false.
1.
Chordates and echinoderms have a common ancestor.
2.
None of the echinoderms living in the oceans today is sessile.
3.
In addition to radial symmetry, echinoderms have a water-vascular system.
4.
The hard, spiny skin of an echinoderm is called an exoskeleton.
5.
All echinoderms except the sand dollar display a five-part radial symmetry.
6.
The adult form of all echinoderms exhibits radial symmetry.
7.
Sea stars are carnivores and are among the most important predators in many marine ecosystems.
8.
In some echinoderms, respiration and waste removal are performed by skin gills.
9.
A separated piece of a sea star can regenerate the rest of its body as long as the piece contains part of the central region of the animal.
 

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
10.
Embryological evidence suggests that the echinoderms are closely related to the
a.
vertebrates.
c.
annelids.
b.
arthropods.
d.
arachnids.
11.
The first organisms to develop a hardened endoskeleton were the
a.
echinoderms.
c.
arthropods.
b.
annelids.
d.
chordates.
12.
Echinoderms
a.
are radially symmetrical as larvae and as adults.
b.
have an exoskeleton as adults.
c.
are bilaterally symmetrical as larvae and radially symmetrical as adults.
d.
are radially symmetrical as larvae and bilaterally symmetrical as adults.
13.
The symmetry exhibited by echinoderms is
a.
bilateral.
c.
radial.
b.
spherical.
d.
mirror image.
14.
In echinoderms and chordates, all the cells of the early embryo
a.
are controlled by molecules within the egg.
b.
form the “first mouth.”
c.
fall into four different categories.
d.
are identical.
15.
The skeleton of an echinoderm is composed of individual plates called
a.
ocelli.
c.
odonata.
b.
ossicles.
d.
isopods.
16.
sea cucumbers : a fused skeleton ::
a.
sea urchins : a five-part body plan
c.
sand dollars : endoskeletons
b.
sea urchins : distinct arms
d.
sea urchins : endoskeletons
17.
Vertebrates, tunicates, and lancelets
a.
are all members of the phylum Chordata.
b.
all have a backbone in the adult stage.
c.
are all marine fish.
d.
are all terrestrial heterotrophs.
18.
Which embryonic chordate characteristics do lancelets retain as adults?
a.
notochord
b.
notochord and dorsal nerve cord
c.
notochord, dorsal nerve cord, and postanal tail
d.
notochord, dorsal nerve cord, postanal tail, and pharyngeal pouches
19.
tunicates : in shallow- and deep-water environments ::
a.
lancelets : buried in mud or sand
b.
lancelets : swimming near the water’s surface
c.
tentacles : in sea urchin mouths
d.
ossicles : in lancelets
20.
Some scientists have hypothesized that the first vertebrates, which were fish, may have evolved from an ancestral tunicate that became sexually mature in the larval form. They suggest that these reproducing larvae were successful and natural selection reinforced the absence of metamorphosis to the adult. Which of the following statements does not support the hypothesis that vertebrates evolved from a sexually mature larval tunicate?
a.
Many invertebrates, tunicate larvae and adults, and the earliest vertebrates are or were filter feeders.
b.
Adult tunicates are sessile and larval tunicates are free-swimming.
c.
The vertebral column of adult vertebrates replaces the notochord present in embryonic vertebrates.
d.
Some living urochordates exist only as free-swimming larvae.


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Darwinian Evolution – PreAP Biology

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Darwinian Evolution – PreAP Biology
  

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 
 1.
Which of the following are examples of fossils?
a.
 shells or old bones
b.
 any traces of dead organisms
c.
 insects trapped in tree sap
d.
 All of the above
 
 2.
Animal fossils may form when
a.
 an animal is buried by sediment.
b.
 an animal is buried on the ocean floor, in swamps, in mud, or in tar pits.
c.
 an animal’s tissue is replaced by harder minerals.
d.
 All of the above
 
 3.
Darwin drew ideas for his theory from observations of organisms on
a.
 the Samoan Islands.
b.
 Manhattan Island.
c.
 the Hawaiian Islands.
d.
 the Galápagos Islands.
 
 4.
The species of finches that Darwin observed differed in the shape of their beaks. According to Darwin, all of these species probably
a.
 had a common ancestor.
b.
 had migrated from Africa.
c.
 had descended from similar birds in Africa.
d.
 ate the same diet.
 
 5.
Darwin thought that the animals of the Galápagos Islands were similar to those of the nearby coast of South America because
a.
 the animals’ ancestors had migrated from South America to the Galápagos Islands.
b.
 the animals had all been brought to the islands by humans.
c.
 the islands had slowly drifted away from the mainland.
d.
 the animals in both places had evolved in nearly identical environments
 
 6.
According to Darwin, evolution occurs
a.
 only through artificial selection.
b.
 during half-life periods of 5,715 years.
c.
 because of natural selection.
d.
 so rapidly that it can be observed easily.
 
 7.
When Darwin published his first book about evolution, he included all of the following ideas except
a.
 the idea that species change slowly over time.
b.
 the idea that some organisms reproduce at a greater rate than others.
c.
 the idea that species are permanent and unchanging.
d.
 the idea that some species become better suited to their environment than others.
 
 8.
The major idea that Darwin presented in his book The Origin of Species was that
a.
 species change over time and never compete with each other.
b.
 animals change, but plants remain the same over time.
c.
 species may change in small ways but cannot give rise to new species.
d.
 species change over time by natural selection.
 
 9.
Natural selection is the process by which
a.
 the age of selected fossils is calculated.
b.
 organisms with traits well suited to their environment survive and reproduce more successfully than organisms less suited to the same environment.
c.
 acquired traits are passed on from one generation to the next.
d.
 All of the above
 
 10.
Populations of the same species living in different places
a.
 do not vary.
b.
 always show balancing selection.
c.
 are genetically identical to each other.
d.
 become increasingly different as each population becomes adapted to its own environment.
 
 11.
Scarcity of resources and a growing population are most likely to result in
a.
 decreased homology.
b.
 increased genetic variation.
c.
 increased competition.
d.
 convergent evolution.
 
   
 
nar001-1.jpg
 
 12.
Refer to the illustration above. An analysis of DNA from these organisms would indicate that
a.
 they have identical DNA.
b.
 they all have the same number of bones.
c.
 their nucleotide sequences show many similarities.
d.
 they all have the same number of chromosomes.
 
 13.
Refer to the illustration above. The similarity of these structures is one form of evidence that the organisms
a.
 share a common ancestor.
b.
 all grow at different rates.
c.
 evolved instantaneously.
d.
 live for a long time.
 
 14.
Refer to the illustration above. The bones labeled “X” can be referred to as
a.
 vestigial structures.
b.
 sequential structures.
c.
 homologous structures.
d.
 fossil structures.
 
 15.
Which of the following is most likely a vestigial structure?
a.
 the human tailbone
c.
 flower color
b.
 the beak of a finch
d.
 a fossil of a snail
 
 16.
Homologous structures in organisms provide evidence that the organisms
a.
 share a common ancestor.
b.
 must have lived at different times.
c.
 have a skeletal structure.
d.
 are now extinct.
 
 17.
Anatomical structures that appear to be derived from a functional structure in an ancestor, but that currently do not serve an important function, are called
a.
 inorganic.
c.
 fossilized.
b.
 mutated.
d.
 vestigial.
 
 18.
The beak of a bird and the beak of a giant squid evolved independently and serve the same function. The beaks are
a.
 divergent structures.
c.
 analogous structures.
b.
 homologous structures.
d.
 hybrid structures.
 
 19.
Evidence that evolution occurs includes all of the following except
a.
 acquired characteristics.
b.
 similarities and differences in proteins and DNA sequences between organisms.
c.
 the fossil record.
d.
 homologous structures among different organisms.
 
 20.

Cytochrome c is a protein that is involved in cellular respiration in all eukaryotic organisms. Human cytochrome c contains 104 amino acids. The following table compares human cytochrome c with cytochrome c from a number of other organisms.

 

Organism		 Number of cytochrome c amino acids
that differ from human cytochrome c amino acids
Chickens
18
Chimpanzees
0
Dogs
13
Rattlesnakes
20
Rhesus monkeys
1
Yeasts
56
   

Which of the following is not a valid inference from these data?

a.
 Chimpanzees are more closely related to humans than yeasts are.
b.
 The cytochrome c of chimpanzees differs from that of rhesus monkeys by only one amino acid.
c.
 Dogs are more closely related to humans than chickens are.
d.
 All of the proteins produced by chimpanzees and humans are identical.
 
 21.
The accumulation of differences between populations that once formed a single population is called
a.
 coevolution.
b.
 adaptation.
c.
 divergent evolution.
d.
 cumulative differentiation.
 
 22.
Over millions of years, plants and their pollinators have
a.
 coevolved.
c.
 become parasites.
b.
 crossbred.
d.
 become competitive.
 
 23.

mc023-1.jpg

Refer to the illustration above. While the shark and dolphin are similar in appearance, dolphins evolved from ancestors that were very different from sharks. The current similarity between sharks and dolphins is an example of

a.
 coevolution.
c.
 convergent evolution.
b.
 biogeography.
d.
 divergent evolution.
 
 24.
What is the idea developed by Charles Lyell which states that the geologic processes that shaped Earth in the past continue to operate in the same way today?
a.
 inheritance of acquired characteristics
b.
 catastrophism
c.
 uniformitarianism
d.
 descent with modification
 
 25.
The idea of inheritance of acquitted characteristics was proposed by
a.
 Charles Darwin.
c.
 Jean-Baptiste Lamarck.
b.
 George Cuvier.
d.
 Charles Lyell.
 
 26.
Which of the following describes a population?
a.
 dogs and cats living in Austin, Texas
b.
 four species of fish living in a pond
c.
 dogwood trees in Middletown, Connecticut
d.
 roses and tulips in a garden
 
 27.
The movement of alleles into or out of a population due to migration is called
a.
 mutation.
c.
 nonrandom mating.
b.
 gene flow.
d.
 natural selection.
 
 28.
What type of population is most susceptible to loss of genetic variability as a result of genetic drift?
a.
 large populations
b.
 medium-sized populations
c.
 small populations
d.
 populations that fluctuate in size
 
 29.
A change in the frequency of a particular gene in one direction in a population is called
a.
 directional selection.
b.
 acquired variation.
c.
 chromosome drift.
d.
 stabilizing selection.
 
 30.
The type of selection that may eliminate intermediate phenotypes is
a.
 direction selection.
b.
 disruptive selection.
c.
 polygenic selection.
d.
 stabilizing selection.
 
 31.
Directional selection tends to eliminate
a.
 both extremes in a range of phenotypes.
b.
 one extreme in a range of phenotypes.
c.
 intermediate phenotypes.
d.
 None of the above; it causes new phenotypes to form.
 
 32.
The large, brightly colored tail feathers of the male peacock are valuable to him because
a.
 they attract potential predators.
b.
 they warn off potential competitors for mates.
c.
 they attract potential mates.
d.
 they attract people who provide them with food.
 
 33.
The hypothesis that evolution occurs at an irregular rate through geologic time is known as
a.
 directional evolution.
b.
 directional equilibrium.
c.
 punctuated equilibrium.
d.
 punctuated evolution.
 

 

 
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Chapter 3 Biochemistry Studyguide

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Chapter 3 Biochemistry Study Guide

 

 

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.
Atoms have a positive charge. _________________________
 2.
Electrons have very little mass. _________________________
 3.
Molecules are atoms that have gained or lost one or more electrons. _________________________
 4.
An atom with more electrons than protons has a positive charge. _________________________
 5.
A covalent bond forms between two atoms that share electrons to form a molecule. _________________________
 6.
Water molecules attract nonpolar molecules such as oil. _________________________
 7.
The ability of water to retain heat helps cells maintain a constant internal temperature. _________________________
 8.
The role of carbohydrates in cells is to supply energy. _________________________
 9.
RNA is made up of a double strand of nucleotides. _________________________
 10.
When cells break down food, the energy from the food is temporarily stored as ATP. _________________________
 11.
The amount of energy needed to cause a chemical reaction to start is called activation energy. _________________________
 12.
Without enzymes, chemical reactions necessary for life would not occur quickly or easily enough to sustain life. _________________________
 13.
When an enzyme binds with its substrate, the activation energy needed for the chemical reaction to occur is increased. _________________________
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 14.
Atoms are not composed of
a.
 protons.
c.
 electrons.
b.
 neutrons.
d.
 chemical bonds
 15.
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.
 16.
The smallest particle of matter that can retain the chemical properties of carbon is a carbon
a.
 molecule.
c.
 atom.
b.
 macromolecule.
d.
 element.
 17.
A substance that is composed of only one type of atom is called a(n)
a.
 compound.
c.
 element.
b.
 cell.
d.
 molecule.
 18.
All matter is composed of
a.
 cells.
c.
 atoms.
b.
 molecules.
d.
 carbon.
 19.
Covalent bonds form when
a.
 two molecules of water share electrons.
b.
 a molecule of water becomes an ion.
c.
 two hydrogen atoms share electrons with one oxygen atom.
d.
 two hydronium ions are attracted to each other.
 20.
Ionic bonds form between particles that have
a.
 opposite charges.
c.
 no charges.
b.
 the same charge.
d.
 neutral charges.
 21.
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.
 22.
Sharing of electrons in the outer energy levels of two atoms
a.
 results in ion formation.
b.
 makes both atoms stable.
c.
 only occurs if both are atoms of the same element.
d.
 is found only among carbon atoms.
 23.
A molecule that has a partial positive charge on one side and a partial negative charge on the other side is called a(n)
a.
 nonpolar molecule.
c.
 charged molecule.
b.
 polar molecule.
d.
 ion.
 24.
Nonpolar molecules have
a.
 no negative or positive ends.
c.
 only a negative end.
b.
 both negative and positive ends.
d.
 only a positive end.
 25.
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.
 26.
Attractions between water molecules are called
a.
 covalent bonds.
c.
 polar bonds.
b.
 ionic bonds.
d.
 hydrogen bonds.
 27.
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.
 28.
Which is not a unique property of water?
a.
 Frozen water floats.
b.
 Water retains a large amount of heat.
c.
 Water molecules stick to each other.
d.
 Water cools rapidly.
 29.
Acidic solutions have a pH that is
a.
 less than 7.
c.
 a negative number.
b.
 between 7 and 14.
d.
 more than 7.
 30.
Hydronium ions, H+, react with hydroxide ions, OH-, to form
a.
 water.
c.
 a base.
b.
 an acid.
d.
 a buffer.
 31.
Which of the following is not a large biomolecule?
a.
 carbohydrate
c.
 lipid
b.
 ice
d.
 nucleic acid
 32.
The building blocks of most biomolecules contain the element
a.
 carbon.
c.
 calcium.
b.
 nitrogen.
d.
 sodium.
 33.
Which of the following molecules are classified as carbohydrates?
a.
 amino acids
c.
 nucleotides
b.
 fats
d.
 sugars
 34.
Polysaccharides are
a.
 carbohydrates.
c.
 proteins.
b.
 lipids.
d.
 nucleic acids.
nar001-1.jpg
nar001-2.jpg
Molecule A
Molecule B
 35.
Refer to the illustration above. Molecule A is a
a.
 carbohydrate.
c.
 nucleic acid.
b.
 lipid.
d.
 protein.
 36.
Plants store glucose in the form of
a.
 starch.
c.
 cellulose.
b.
 glycogen.
d.
 chitin.
 37.
Which of the following is a carbohydrate?
a.
 ATP
c.
 wax
b.
 steroid
d.
 sucrose
 38.
Lipids are
a.
 soluble in water.
b.
 made of chains of amino acids.
c.
 linked together with peptide bonds.
d.
 used by the body for storing energy.
 39.
All of the following are examples of lipids except
a.
 oil.
c.
 steroids.
b.
 starch.
d.
 candle wax.
 40.
Which molecules are most closely related to lipids?
a.
 amino acids
b.
 long chains of carbon and hydrogen
c.
 nucleotides
d.
 sugars
 41.
Which of the following molecules are most closely related to proteins?
a.
 amino acids
c.
 nucleotides
b.
 monosaccharides
d.
 sugars
 42.
Long chains of amino acids are found in
a.
 carbohydrates.
c.
 proteins.
b.
 lipids.
d.
 sugars.
 43.
The overall shape of a single chain of amino acids in a protein is that protein’s
a.
 primary structure.
c.
 tertiary structure.
b.
 secondary structure.
d.
 quaternary structure.
 44.
The amino group of one amino acid is linked to the carboxyl group of another amino acid in a protein. This link is a(n)
a.
 peptide bond.
c.
 ionic bond.
b.
 hydrogen bond.
d.
 polar bond.
 45.
What gives each amino acid its unique properties?
a.
 its side group
c.
 its carboxyl group
b.
 its amino group
d.
 its sequence
 46.
The two types of nucleic acids are
a.
 RNA and ATP.
c.
 DNA and ATP.
b.
 DNA and RNA.
d.
 nucleotides and ATP.
 47.
Which of the following molecules are most closely related to nucleic acids?
a.
 amino acids
c.
 nucleotides
b.
 fats
d.
 sugars
 48.
DNA stores
a.
 fat.
c.
 energy.
b.
 carbohydrates.
d.
 hereditary information.
 49.
The two strands of a DNA molecule are held together by
a.
 ionic bonds.
c.
 hydrogen bonds.
b.
 covalent bonds.
d.
 peptide bonds.
 50.
Which of the following is not part of a nucleotide in a DNA molecule?
a.
 three phosphate groups
c.
 a base
b.
 a sugar
d.
 a phosphate group
 51.
ATP (adenosine triphosphate) stores energy in the bonds between its
a.
 hydrogen atoms.
c.
 nucleotides.
b.
 carbon atoms.
d.
 phosphate groups.
 52.
When paper burns, the paper combines with oxygen to form carbon dioxide and water vapor. How does the mass of carbon dioxide plus water vapor compare with the mass of the paper plus oxygen?
a.
 The mass of carbon dioxide plus water vapor is greater than that of paper plus oxygen.
b.
 The mass of carbon dioxide plus water vapor is less than that of paper plus oxygen.
c.
 It is impossible to tell.
d.
 The mass of carbon dioxide plus water vapor is identical to that of paper plus oxygen.
 53.
The law of conservation of energy states that energy cannot be
a.
 changed from one form to another.
b.
 taken from the surroundings in a reaction.
c.
 released into the surroundings in a reaction.
d.
 created or destroyed in a chemical reaction.
 54.
A chemical reaction will probably occur between two substrate molecules if they
a.
 are far apart.
b.
 are aligned in the wrong spatial orientation.
c.
 have large amounts of kinetic energy.
d.
 have little kinetic energy.
 55.
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 enzymes on reactants.
nar002-1.jpg
 56.
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 occurs 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 at the end of the reaction.
d.
 Product B contains more energy at the end of the reaction than reactant A has at the beginning of the reaction.
 57.
Refer to the illustration above. Reaction 3 in the graph
a.
 probably occurred in the presence of an enzyme.
b.
 requires more activation energy than Reaction 2.
c.
 is the same as Reaction 1, but faster.
d.
 is slower than Reaction 2.
 58.
The molecule on which an enzyme acts is called a(n)
a.
 active site.
c.
 polar molecule.
b.
 inactive site.
d.
 substrate.
 59.
An enzyme
a.
 is used up in a reaction.
b.
 raises the activation energy of a reaction.
c.
 bonds with an active site on a substrate molecule.
d.
 lowers the activation energy of a reaction.
 60.
Enzymes
a.
 are able to heat up molecules so that they can react.
b.
 always provide carbon dioxide for chemical reactions.
c.
 hold substrate molecules in the correct alignment.
d.
 absorb excess heat so that reactions occur at low temperatures.
 61.
A cell contains
a.
 thousands of different kinds of enzymes, each assisting in a different chemical reaction.
b.
 one kind of enzyme that assists in thousands of different chemical reactions.
c.
 approximately 100 kinds of enzymes, each assisting in a different chemical reaction.
d.
 one enzyme that assists in reactions involving protein substrates and one enzyme that assists in reactions involving substrates that are not proteins.
 

Completion
Complete each statement.
 62.
The negatively charged particles in an atom are ____________________.
 63.
Protons and neutrons are found in the ____________________ of an atom.
 64.
A(n) ____________________ is a group of atoms held together by covalent bonds.
 65.
Sodium chloride, NaCl, is an example of a(n) _________________.
 66.
A(n) ____________________ bond forms between two atoms sharing electrons.
 67.
The attraction between oppositely charged ions results in the formation of a(n) ____________________.
 68.
Weak chemical attractions between polar molecules are ____________________ bonds.
 69.
Lipids are ____________________ molecules because they have no negative and positive poles.
 70.
Water heats and cools ____________________.
 71.
The attraction that causes water and other liquids to form drops and thin films is ____________________.
 72.
The medium in which most cellular events take place is ____________________.
 73.
Substances with a pH less than 7 are ____________________.
 74.
Substances with a pH greater than 7 are ____________________.
 75.
The pH scale measures the concentration of ____________________ ions in solutions.
 76.
A carbon atom can bond with four other atoms because it has ____________________ valence electrons.
 77.
A(n) ____________________ contains carbon, hydrogen, and oxygen in a ratio of 1:2:1.
 78.
Amino acids are the building blocks of __________________.
 79.
Most proteins consist of two or more ________________ that twist and fold around each other.
 80.
Long chains of nucleotides are called ____________________.
 81.
The ability to move or change matter is ____________________.
 82.
All living things require a source of ____________________ to carry out their life activities.
 83.
The starting materials for chemical reactions are called ____________________, while the new substances that are formed are called ____________________.
 84.
The energy needed to start a chemical reaction is called ____________________.
 85.
A biochemical reaction can be speeded up by adding a(n) ____________________, which lowers the amount of activation energy required to start the reaction.
 86.
The portion of an enzyme molecule into which a specific substrate can fit is called the ____________________.
 

Short Answer
 87.
How many different kinds of atoms are there in an element?
 88.
How does an atom become an ion?
 89.
An ionic bond forms between what two kinds of particles?
 90.
What makes a water molecule polar?
 91.
How well do nonpolar molecules dissolve in water?
 92.
What is an attraction between particles of different substances called?
 93.
What are the two most common elements found in large biomolecules?
 94.
What is the function of lipids in cells?
 95.
What determines the primary structure of a protein?
 96.
Where do your cells get most of the energy they need for metabolism?
 97.
How do enzymes speed up a chemical reaction?
 

Problem
 98.

The following statements are about the molecule ATP (adenosine triphosphate). For each statement, first determine whether it is true or false. Then, if it is false, rewrite the statement so that it is correct.

a. ATP is chemically similar to a carbohydrate.
b. Cells require ATP to function.
c. None of the energy in food molecules is stored in ATP.
d. ATP is the primary source of energy for chemical reactions occurring in all cells of all living organisms.

nar003-1.jpg
 99.

Refer to the illustration above. The graph depicts the relative energy levels of the products and reactants for the following chemical reaction: A + B « C + D.

a. Which substances, A, B, C, and/or D, are present at point 1 on the graph?
b. Which substances, A, B, C, and/or D, are present at point 3 on the graph?
c. Why is point 2 at a higher energy level than point 1?
d. Why is point 3 at a lower energy level than point 1?
e. Draw a dashed line on the graph indicating how the energy level of this reaction over time would be different if the enzyme that catalyzes the reaction were not present.

Enzymes catalyze a variety of biological reactions. The extent to which they can speed up the rate of a reaction is dependent on a number of factors. Draw a graph for the following condition(s), showing the effect of altering one factor on the relative rate of a reaction. Use “0” to indicate no activity, and “1” through “10” to indicate increasing rate of reaction from very low to very high. Include a label for your graph(s).
 100.
Refer to the paragraph above, and then draw your graph in the space below. Enzyme #1 is inactive between 0°C and 10°C. It is active above 10°C, with the rate increasing steadily until the temperature reaches 40°C. At 40°C, the rate of the reaction is very high. Above 40°C, the rate decreases steadily until the temperature reaches 60°C, at which point the enzyme is no longer active.
 101.
Refer to the paragraph above, and draw your graph. Enzyme #2 is inactive at a pH of 1–4. It is active above a pH of 4, with the rate increasing slowly until the pH reaches 6. Above a pH of 6, the rate increases sharply until the pH reaches 7. Above a pH of 7, the rate decreases sharply until the pH reaches 8. Above a pH of 8, the rate decreases gradually until the pH reaches 10, at which point the enzyme is no longer active.
 102.
Refer to the paragraph above, and draw your graph. Enzyme #3 is inactive when the concentration of the substrate it acts upon is zero. The enzyme is active when the substrate concentration is above zero, with the rate increasing only very slightly until the concentration reaches 30%. Above 30%, the rate increases very sharply to a high level, until the concentration reaches 60%. Above a concentration of 60%, the rate increases very little. The rate does not increase when the substrate concentration is above 80%.
 

Essay
 103.
Describe how an enzyme can function in speeding up a chemical reaction within a cell.

 
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Internal Anatomy of the Fetal Pig Exam

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Internal Anatomy of the Fetal Pig Exam

1. What does the letter L refer to in the figure of the internal anatomy of the fetal pig?

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2. In the figure of the internal anatomy of the fetal pig, what letter refers to the thyroid gland?

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3. In the figure of the internal anatomy of the fetal pig, what letter refers to the left lung?

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4. What does the letter C refer to in the figure of the internal anatomy of the fetal pig?

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5. What does the letter J refer to in the figure of the internal anatomy of the fetal pig?

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6. In the figure of the internal anatomy of the fetal pig, what letter refers to the urinary bladder?

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7. What does the letter M refer to in the figure of the internal anatomy of the fetal pig?

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8. What does the letter A refer to in the figure of the internal anatomy of the fetal pig?

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9. In the figure of the internal anatomy of the fetal pig, what letter refers to the diaphragm?

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10. What does the letter F refer to in the figure of the internal anatomy of the fetal pig?

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11. In the figure of the internal anatomy of the fetal pig, what letter refers to the liver?

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12. In the figure of the internal anatomy of the fetal pig, what letter refers to the right common carotid artery?

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13. What does the letter N refer to in the figure of the internal anatomy of the fetal pig?

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14. What does the letter G refer to in the figure of the internal anatomy of the fetal pig?

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15. What does the letter E refer to in the figure of the internal anatomy of the fetal pig?

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16. In the figure of the internal anatomy of the fetal pig, what letter refers to the small intestine?

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17. In the figure of the internal anatomy of the fetal pig, what letter refers to the heart?

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18. In the figure of the internal anatomy of the fetal pig, what letter refers to the umbilical vein?

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19. What does the letter B refer to in the figure of the internal anatomy of the fetal pig?

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20. In the figure of the internal anatomy of the fetal pig, what letter refers to the larynx?

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21. What does the letter K refer to in the figure of the internal anatomy of the fetal pig?

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22. In the figure of the internal anatomy of the fetal pig, what letter refers to the left common carotid artery?

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23. In the figure of the internal anatomy of the fetal pig, what letter refers to the umbilical arteries?

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24. In the figure of the internal anatomy of the fetal pig, what letter refers to the large intestine?

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25. What does the letter H refer to in the figure of the internal anatomy of the fetal pig?

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26. What does the letter I refer to in the figure of the internal anatomy of the fetal pig?

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27. What does the letter D refer to in the figure of the internal anatomy of the fetal pig?

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28. In the figure of the internal anatomy of the fetal pig, what letter refers to the right lung?

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