Author: Biology Junction Team

Plant Evolution, Structure, and Function

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Plant Evolution, Structure, and Function

 

 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 1.
The ancestors of today’s land plants were probably
a.
 brown algae.
c.
 green algae.
b.
 red algae.
d.
 lichens.
 2.
The challenges faced by early land plants included
a.
 conserving water.
b.
 reproducing on land.
c.
 absorbing minerals from the rocky surface.
d.
 All of the above
 3.
The waxy protective covering of a land plant is called a
a.
 cuticle.
c.
 rhizome.
b.
 capsule.
d.
 stoma.
 4.
The cuticle
a.
 helps reduce the evaporation of fluids from a plant.
b.
 is a plant adaptation to an aquatic environment.
c.
 is a reproductive structure in some plants.
d.
 is crucial to plant cell nourishment.
 5.
Some land plants developed an internal system of interconnected tubes and vessels called
a.
 cuticles.
b.
 nonvascular canals.
c.
 the circulatory system.
d.
 vascular tissues.
 6.
The xylem in a plant
a.
 transports food from the leaves.
b.
 transports water and minerals to the stems and leaves.
c.
 exchanges carbon dioxide with the atmosphere.
d.
 All of the above
 7.
liverworts, hornworts, mosses : nonvascular plants ::
a.
 gymnosperms, angiosperms : bryophytes
b.
 ferns : mosses
c.
 gymnosperms, angiosperms : vascular plants
d.
 bryophytes, liverworts : vascular plants
 8.
gymnosperms : naked seeds ::
a.
 pollen : mosses
b.
 ferns : seeds
c.
 liverwort : vascular tissue
d.
 angiosperms : enclosed seeds
 9.
The diploid form in a plant’s life cycle is called the
a.
 sporophyte.
b.
 gametophyte.
c.
 parental generation.
d.
 alternate generation.
 10.
The haploid form in a plant’s life cycle is called the
a.
 sporophyte.
b.
 gametophyte.
c.
 parental generation.
d.
 alternate generation.
 11.
Alternation between a haploid stage and a diploid stage in a plant’s life cycle is called
a.
 generational recycling.
b.
 periodic gametogenesis.
c.
 alternating forms.
d.
 alternation of generations.
 12.
In plants, haploid gametes are produced as a result of
a.
 fertilization.
c.
 encapsulation.
b.
 meiosis.
d.
 mitosis.
 13.
The dominant generation in vascular plants is the
a.
 gametophyte.
c.
 angiosperm.
b.
 gymnosperm.
d.
 sporophyte.
 14.
vascular plants : sporophytes ::
a.
 sporophytic plants : gametophytes
b.
 nonvascular plants : gametophytes
c.
 spores : gametes
d.
 plants with seeds : seedless plants
 15.
sporophytes : spores ::
a.
 sporophytes : gametophytes
b.
 gametophytes : gametes
c.
 gametophytes : spores
d.
 sporophytes : gametes
 16.
Which of the following is not a nonvascular plant?
a.
 moss
c.
 hornwort
b.
 liverwort
d.
 fern
 17.
Which of the following is not characteristic of all nonvascular plants?
a.
 They produce seeds.
b.
 They have a life cycle characterized by alternation of generations.
c.
 They produce spores.
d.
 They require water for sexual reproduction.
 18.
Which of the following is a reason why mosses are good pioneer plants?
a.
 They can survive in very wet areas.
b.
 They can survive in areas that receive only low levels of sunlight.
c.
 They can create a layer of soil on bare rock.
d.
 They grow very slowly.
 19.
The water-retaining ability of peat moss makes it ideal for
a.
 use in garden-soil mixes.
b.
 use in packing bulbs and flowers for shipping.
c.
 use in houseplant soils.
d.
 All of the above
 20.
All of the following developed in some vascular plants and are not present in any nonvascular plants except
a.
 pollen.
c.
 chlorophyll.
b.
 deep roots.
d.
 seeds.
 21.
The primary distinguishing characteristics of all vascular plants are
a.
 xylem and phloem; true roots, stems, and leaves; pollen; seeds.
b.
 xylem and phloem; true roots, stems, and leaves; spores.
c.
 true roots, stems, and leaves; spores.
d.
 xylem and phloem; true roots, stems, and leaves.
 22.
Which of the following is not a seed plant?
a.
 a flowering plant
c.
 a fern
b.
 a pine tree
d.
 a ginkgo
 23.
Which of the following is characteristic of all seed plants?
a.
 a seed containing an embryo, a nutrient supply, and a protective coat
b.
 enclosure and protection of seeds within a fruit
c.
 production of flowers
d.
 All of the above
 24.
Pines, spruces, and firs are
a.
 angiosperms.
c.
 flowering plants.
b.
 gymnosperms.
d.
 sometimes nonvascular.
 25.
The tallest trees in the world are species of
a.
 conifers.
c.
 liverworts.
b.
 dicots.
d.
 angiosperms.
 26.
Which of the following were the first land plants to evolve seeds?
a.
 angiosperms
c.
 mosses
b.
 gymnosperms
d.
 ferns
 27.
Seed plants are the dominant land plants because
a.
 they include the largest plants on Earth.
b.
 the seeds they produce enable the plant to survive in a dormant state when conditions are not suitable for growth.
c.
 they are vascular plants with large root systems, so they can obtain water from any kind of environment.
d.
 they produce flowers that are pollinated by insects, enabling them to produce many offspring.
 28.
Monocots have
a.
 leaves with branching veins.
b.
 flower parts in multiples of four or five.
c.
 leaves with parallel veins.
d.
 two cotyledons.
 29.
Flowering plants are classified as monocots or dicots according to their number of
a.
 leaves.
c.
 meristems.
b.
 roots.
d.
 cotyledons.
 30.
Which of the following associations between a plant cell type and its characteristics is incorrect?
a.
 collenchyma cell—thin cell walls; do not occur in groups
b.
 parenchyma cell—cube-shaped or elongated; large vacuole
c.
 sclerenchyma cell—thick, rigid cell walls
d.
 All of the above are correct.
 31.
Which of the following types of plant cells provides structural support and is typically dead at functional maturity?
a.
 collenchyma
c.
 sclerenchyma
b.
 parenchyma
d.
 None of the above
 32.
The conducting cells of phloem are called
a.
 tracheids.
c.
 sieve plates.
b.
 sieve tube members.
d.
 vessel elements.
 33.
In xylem tissue, water moves from tracheid to tracheid through
a.
 pits.
c.
 sieve tubes.
b.
 vessel elements.
d.
 companion cells.
 34.
The outermost layer consisting of ground tissue in a stem is the
a.
 sapwood.
c.
 pith.
b.
 nodes.
d.
 cortex.
 35.
vascular tissue : transport of fluids ::
a.
 epidermis : support
b.
 dermal tissue : storage
c.
 dermal tissue : transport of fluids
d.
 ground tissue : metabolism
 36.
Regions of active cell division in plants are called
a.
 meristems.
c.
 phloem.
b.
 xylem.
d.
 dermal tissue.
 37.
Meristems can be found
a.
 only at the tips of roots.
b.
 only at the tips of stems.
c.
 at the tips of stems and roots.
d.
 None of the above
 38.
Which of the following types of meristems is found in some monocots above the bases of leaves and stems?
a.
 apical meristems
b.
 vascular cambium
c.
 intercalary meristems
d.
 cork cambium
 39.
The lengthening of plant roots and shoots is called
a.
 secondary growth.
c.
 primary growth.
b.
 germination.
d.
 vascular growth.
 40.
During periods of primary growth at apical meristems, stems and roots
a.
 become wider.
b.
 become longer.
c.
 maintain a constant number of cells.
d.
 undergo photoperiodism.
 41.
secondary growth : width ::
a.
 secondary growth : height
b.
 lateral meristem : length
c.
 apical meristem : width
d.
 primary growth : length
 42.
The primary function of root hairs is
a.
 to strengthen roots as they grow downward.
b.
 to transport food up the stem.
c.
 to absorb water and minerals.
d.
 to store water.
 43.
leaves : carbon dioxide from the air ::
a.
 leaves : water from the air
b.
 roots : light from the air
c.
 roots : carbon dioxide from the air
d.
 roots : nutrients from the soil
 44.
Which of the following are taproots?
a.
 underground roots of grass plants
b.
 prop roots of corn plants
c.
 roots of radish plants
d.
 aerial roots of orchids
 45.
Which of the following is not characteristic of fibrous roots?
a.
 many branch roots
b.
 shallow roots
c.
 dominant primary root
d.
 possible development from the base of the stem
 46.
Which of the following is not characteristic of secondary growth of roots?
a.
 Vascular cambium is formed.
b.
 Secondary xylem is produced toward the inside of the root and secondary phloem is produced toward the outside of the root.
c.
 Cork cambium is formed.
d.
 It occurs in monocot, dicot, and gymnosperm roots.
 47.
Which of the following is the function of the endodermis?
a.
 water absorption
b.
 water storage
c.
 regulation of passage of water and minerals into the vascular tissue
d.
 production of new cells for secondary growth
The diagram below shows the stem of a coleus plant.

nar001-1.jpg
 48.
Refer to the illustration above. The tissue labeled “1” in the diagram is called
a.
 meristem.
c.
 phloem.
b.
 xylem.
d.
 ground tissue.
 49.
Refer to the illustration above. In the diagram, the tissue labeled “2,” which conducts water and is made of elongated cells that connect end to end, is called
a.
 meristem.
c.
 phloem.
b.
 xylem.
d.
 ground tissue.
 50.
Refer to the illustration above. In the diagram, the tissue labeled “3,” which transports sugars from regions where they are made to regions where they are used, is called
a.
 meristem.
c.
 phloem.
b.
 xylem.
d.
 ground tissue.
 51.
The ground tissue in the center of roots and stems
a.
 turns into meristem.
b.
 transports food.
c.
 provides support.
d.
 germinates at least once a year.
 52.
Leaves connect to the stems of plants at the
a.
 lateral buds.
c.
 nodes.
b.
 pith.
d.
 internodes.
 53.
Secondary xylem and phloem are produced from the
a.
 cork cambium.
c.
 apical meristems.
b.
 vascular cambium.
d.
 bark.
 54.
xylem : inner side of vascular cambium ::
a.
 vascular cambium : cork cambium
b.
 cork : vascular cambium
c.
 phloem : outer side of vascular cambium
d.
 phloem : inner side of vascular cambium
 55.
Bark contains
a.
 xylem and phloem.
c.
 phloem and cork cells.
b.
 sapwood.
d.
 mesophyll.
 56.
In a woody stem, cork cambium
a.
 forms phloem.
b.
 forms xylem.
c.
 produces the outer bark.
d.
 becomes vascular cambium.
 57.
The movement of water through a plant is caused by
a.
 the attraction of water molecules for each other.
b.
 capillary action.
c.
 transpiration.
d.
 All of the above
 58.
The loss of water by the leaves and stem of a plant is called
a.
 translocation.
c.
 active transport.
b.
 osmosis.
d.
 transpiration.
 59.
The phloem in a plant
a.
 transports sugars.
b.
 transports water and minerals.
c.
 exchanges carbon dioxide and oxygen with the atmosphere.
d.
 None of the above
 60.
The transport of food from the leaf to the rest of the plant is called
a.
 translocation.
c.
 active transport.
b.
 osmosis.
d.
 transpiration.
 61.
A hypothesis that explains the movement of sugar in a plant is the
a.
 transpiration hypothesis.
c.
 pressure-flow hypothesis.
b.
 translocation hypothesis.
d.
 source-sink hypothesis.
 62.
cohesion : adhesion ::
a.
 hydrogen : polar
c.
 hand : people
b.
 book : pages
d.
 night : day
The diagram below shows a portion of a plant’s vascular system.

nar002-1.jpg
 63.
Refer to the illustration above. Structure 2 is a
a.
 tracheid.
c.
 vessel element.
b.
 companion cell.
d.
 sieve tube member.
 64.
Refer to the illustration above. Structure 3 is a
a.
 tracheid.
c.
 vessel element.
b.
 companion cell.
d.
 sieve tube member.
 65.
Refer to the illustration above. Which structure allows the cytoplasm of one cell to connect to the cytoplasm of a neighboring cell?
a.
 1
c.
 4
b.
 3
d.
 5
 66.
The xylem in a plant
a.
 transports sugars.
b.
 transports water and minerals.
c.
 exchanges carbon dioxide and oxygen with the atmosphere.
d.
 None of the above
 67.

Scientists studying the transport of sugars in plants found it difficult to conduct experiments that didn’t damage the plants they were studying. Some of them decided to use some insects they knew fed on plants. The insects they chose were aphids, which have mouthparts that they insert into plants and use to suck out nutrients. Many of these aphids also release excess sugars from the anal end of their digestive tracts. These substances are called honeydew because they are released as sugary droplets. The scientists conducted the following experiments:

(1) They measured the rate at which honeydew was released from aphids feeding on cucumber plants. The average rate was two drops per hour.
(2) They froze some aphids and the plant parts to which the aphids were attached. They then examined cross sections of the plant parts using an electron microscope. They found that the tips of the aphids’ mouthparts were in individual cells in the phloem tissue.
(3) They anesthetized aphids feeding on plants and then cut away the aphids, leaving the mouthparts in place. They noted that the honeydew continued to be released through the mouthparts at a rate of two drops per hour. They also analyzed the honeydew and found that it had the same chemical composition as the sugars transported in the plants.

Which of the following statements is not supported by the data obtained in these experiments?

a.
 The contents of the phloem are under pressure.
b.
 Sugars are transported in the phloem of plants.
c.
 Sugars are actively transported into cells of the phloem.
d.
 Some aphids take up more sugars from plants than they can use.
 68.
mc068-1.jpg

Refer to the illustration above. Which of the leaves is a doubly compound leaf?

a.
 1
c.
 3
b.
 2
d.
 4
 69.
In plants, the ground tissue that is made up of chloroplast-rich cells is the
a.
 vascular bundle.
c.
 pith.
b.
 petiole.
d.
 mesophyll.
 70.
The tissue of the leaf mesophyll that is located directly below the upper epidermis and consists of tightly packed column-shaped cells is the
a.
 palisade layer.
c.
 adventitious layer.
b.
 cortex.
d.
 spongy mesophyll.
The diagram below shows a leaf cross section.

nar003-1.jpg
 71.
Refer to the illustration above. Which label indicates the spongy layer?
a.
 2
c.
 4
b.
 3
d.
 5
 72.
Refer to the illustration above. Structure 1
a.
 is the cuticle.
c.
 covers the epidermis.
b.
 protects the leaf.
d.
 All of the above
 73.
Refer to the illustration above. The vein is made up of
a.
 only xylem vessels.
b.
 only phloem vessels.
c.
 both xylem and phloem vessels.
d.
 neither xylem nor phloem vessels.
 74.
Photosynthesis enables plants to produce most of the organic molecules they need. This process requires the use of all of the following except
a.
 carbon dioxide.
c.
 light.
b.
 water.
d.
 glucose.
 75.
Which of the following is an adaptation found in leaves of shade-grown plants?
a.
 high density of chloroplasts
b.
 small leaf area
c.
 chloroplasts not shading each other
d.
 dense hair coatings
 76.
The stomata are responsible for
a.
 translocation.
b.
 leaf growth.
c.
 regulation of water loss.
d.
 transport of minerals.
 77.
The guard cells that surround a stoma
a.
 have no cell walls.
b.
 swell with water, causing the stoma to open.
c.
 shrivel up when opening the stoma.
d.
 are responsible for translocation.
 78.
guard cells : stomata ::
a.
 can openers : cans
c.
 cushions : rocking chairs
b.
 hammers : nails
d.
 trout : stream
 79.
cuticle : above-ground parts ::
a.
 vascular system : plant
c.
 guard cell : stoma
b.
 sperm : pollen
d.
 root system : wax
 

Completion
Complete each statement.
 80.
In leaves, the openings called ____________________ regulate the exchange of carbon dioxide and oxygen.
 81.
The surface of a vascular plant is covered by a waxy, waterproof layer called a(n) ____________________.
 82.
One of the first environmental challenges that early land plants had to overcome was finding a way to conserve ____________________.
 83.
The tissues that transport water and minerals within a plant make up the ____________________ system.
 84.
____________________ are seed plants with uncovered seeds.
 85.
In alternation of generations, the ____________________ generation alternates with the diploid generation.
 86.
co086-1.jpg

Refer to the illustration above. The cycle shown in the diagram is referred to as _________________________.
 87.
The fusion of two gametes results in the production of a(n) ____________________ sporophyte.
 88.
The haploid form of a plant is the ____________________ generation.
 89.
Conifers produce ____________________ to protect their seeds.
 90.
The sporophyte generation produces haploid spores by the process of ____________________.
 91.
Peat bogs contain organic matter that decomposes very slowly because of a(n) ____________________ produced by peat moss.
 92.
Bryophytes have a dominant ____________________ generation.
 93.
In mosses and liverworts, the ____________________ generation is the dominant generation.
 94.
A rootlike structure that anchors plants in the phylum Bryophyta is called a(n) ____________________.
 95.
The ability of mosses to absorb and retain ____________________ contributes to their ability to help prevent soil erosion.
 96.
Partially decomposed moss plants of the genus Sphagnum are dried and used as a source of ____________________ for heating.
 97.
A plant that has flower parts that occur in multiples of four or five is usually a(n) ____________________.
 98.
Most ____________________ have thin, transparent leaflike structures along a stemlike axis.
 99.
Nonvascular plants known as ____________________ usually have cells with a single large chloroplast, similar to algae.
 100.
Photosynthetic and storage tissues of plants are made up of ____________________ cells.
 101.
____________________ are narrow, elongated, thick-walled sclerenchyma cells that taper at each end.
 102.
The lateral meristem that produces secondary vascular tissue is called the _________________________.
 103.
The lateral meristem that produces the cork cells of the outer bark is called the ____________________.
 104.
Plants grow at the tips of roots and stems in regions of active cell division called ____________________.
 105.
Cell division in the ____________________ adds layers of new cells around the outside of a plant’s body.
 106.
Growth that occurs from the formation of new cells at the tip of a plant is called ____________________.
 107.
Growth that causes a plant to increase in width is called _________________________.
 108.
The thickening of a plant body by the production of new xylem and phloem is called ____________________ growth.
 109.
The ____________________ of plants absorb water and minerals necessary for growth.
 110.
The two main types of root systems are fibrous root systems and ____________________ systems.
 111.
Primary growth in roots occurs in cells of the _________________________, carbohydrate storage occurs in cells of the ____________________, and water absorption occurs through cells of the ____________________.
 112.
Flexible, soft, and usually green stems are called ____________________ stems.
 113.
Edible parts of the potato plant are modified stems called ____________________, which grow underground and store starch.
 114.
The darker wood in the center of a tree trunk is called ____________________.
 115.
Wood consists primarily of _________________________ cells.
 116.
The transport of organic molecules from the leaf to the rest of the plant is called ____________________.
 117.
The broad, flat portion of a typical leaf is called the ____________________.
 118.
When the guard cells that surround a stoma fill with water, the stoma ____________________.
 119.
____________________ ions play an important role in opening and closing stomata.
 

Problem
 120.

pr120-1.jpg

Refer to the illustration above. This cladogram depicts the presumed evolutionary relationships between the major phyla of land plants. The list below consists of paired characteristics found in at least some land plants. For each pair of characteristics, choose the one that is the more evolutionarily advanced. Then complete the cladogram by indicating on it where each of the more advanced characteristics first appeared.

Characteristics:

cones / flowers
sporophyte dominant / gametophyte dominant
waxy cuticle present / waxy cuticle absent
vascular tissue absent / vascular tissue present
gametophyte independent of sporophyte / gametophyte dependent on sporophyte
stomata absent / stomata present
seeds / spores
multicellular reproductive structure / unicellular reproductive structure
 

Essay
 121.
What problems were encountered by the first land plants? What adaptations evolved to solve these problems? Write your answer in the space below.
 122.
How is a seed an adaptation for life on land? Write your answer in the space below.
 123.
Describe three characteristics of angiosperms that have helped to make the group successful. Write your answer in the space below.
 124.
Describe the functions of ground tissue in a plant. Write your answer in the space below.
 125.
What kinds of plants have lateral meristems, and what kind of growth occurs in the lateral meristems? Write your answer in the space below.
 126.
While walking through a forest you notice that someone has carved his or her initials into the bark of a tree. The initials are exactly 1.5 meters from the ground. How far from the ground will the initials be next year and the year after that? Why? Discuss growth tissues in plants in your answer. Write your answer in the space below.
 127.
Secondary growth adds width to a woody stem. Briefly describe the tissues involved and explain how they increase the stem’s diameter. Write your answer in the space below.
 128.
Define the terms source and sink in relation to the transportation of organic molecules in the phloem of plants. Write your answer in the space below.
 129.
Compare the movement of sugar and water in a plant. Write your answer in the space below.
 130.
Why is it advantageous for mesophyll cells to be more densely packed in the upper part of a plant leaf than in the lower part? Write your answer in the space below.
 131.
Describe how stomata open and close. Write your answer in the space below.


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Image:Cnemidophorus-ThreeSpecies.jpg – Wikipedia, the free encyclopedia

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Shows three species of the lizard genus Cnemidophorus, commonly known as whiptails: C. inornatus, C. neomexicanus, C. tigris.

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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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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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Nucleic Acids

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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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