Question 1

Perhaps the best-known _______ are the malarial parasites of the genus Plasmodium.

Accepted Answer

A)  radiolarians 
B)  stramenopiles 
C)  dinoflagellates 
D)  apicomplexans 
E)  ciliates 
A)  radiolarians 
B)  stramenopiles 
C)  dinoflagellates 
D)  apicomplexans 
E)  ciliates

Question 2

The ancestor of photosynthetic euglenids took up the chloroplast of a green alga.This explains why photosynthetic euglenids

Accepted Answer

A)  have a flagellum. 
B)  have the same photosynthetic pigments as plants. 
C)  are ancestral to land plants. 
D)  have two nuclei. 
E)  lose their photosynthetic pigments when kept in the dark. 
A)  have a flagellum. 
B)  have the same photosynthetic pigments as plants. 
C)  are ancestral to land plants. 
D)  have two nuclei. 
E)  lose their photosynthetic pigments when kept in the dark.

Question 3

Refer to the gene tree shown.   Ribosomal RNA genes are present in the nuclear genomes of eukaryotes.There are also rRNA genes in the genomes of mitochondria and chloroplasts.Therefore photosynthetic eukaryotes have three different sets of rRNA genes, which encode the structural RNA of three separate sets of ribosomes.Translation of each genome takes place on its own set of ribosomes.The gene tree shows the evolutionary relationships among rRNA gene sequences isolated from the nuclear genomes of humans, yeast, and corn; from an archaeal species (Halobacterium), a proteobacterium (E.coli), and a cyanobacterium (Chlorobium); and from the mitochondrial and chloroplast genomes of corn.Based on the gene tree, why aren't the three rRNA genes of corn one another's closest relatives?

Accepted Answer

The three rRNA genes of corn are not one

Question 4

Which statement about cellular slime molds is false?

Accepted Answer

A)  The feeding stage is made up of individual cells called myxamoebas. 
B)  The slug, or pseudoplasmodium, contains numerous nuclei within a single cell membrane. 
C)  Swarms of independent, isolated cells persist while food and moisture are available. 
D)  Individual myxamoebas are haploid cells. 
E)  In unfavorable conditions, myxamoebas aggregate and form fruiting structures. 
A)  The feeding stage is made up of individual cells called myxamoebas. 
B)  The slug, or pseudoplasmodium, contains numerous nuclei within a single cell membrane. 
C)  Swarms of independent, isolated cells persist while food and moisture are available. 
D)  Individual myxamoebas are haploid cells. 
E)  In unfavorable conditions, myxamoebas aggregate and form fruiting structures.

Question 5

Euglenids are single-celled freshwater organisms that move by using _______.

Accepted Answer

The answer of Euglenids are single-celled freshwater organisms that move...

Question 6

Hydrocarbons extracted from geological formations that are currently a source of petroleum were produced from the ancient buried remains of

Accepted Answer

A)  radiolarians. 
B)  diatoms. 
C)  foraminiferans. 
D)  slime molds. 
E)  ciliates. 
A)  radiolarians. 
B)  diatoms. 
C)  foraminiferans. 
D)  slime molds. 
E)  ciliates.

Question 7

Which term refers to a eukaryotic organism that undergoes alternation of generations in which different generations do not resemble each other morphologically?

Accepted Answer

A)  Homomorphic 
B)  Heteromorphic 
C)  Isomorphic 
D)  Anisomorphic 
E)  Gametophytic 
A)  Homomorphic 
B)  Heteromorphic 
C)  Isomorphic 
D)  Anisomorphic 
E)  Gametophytic

Question 8

Because silica resists compression, spiny remains of fossils of _______ can be used in "Earth-friendly" insecticides, to physically disrupt insect body functions in insects.

Accepted Answer

A)  radiolarians 
B)  brown algae 
C)  foraminiferans 
D)  diatoms 
E)  euglenids 
A)  radiolarians 
B)  brown algae 
C)  foraminiferans 
D)  diatoms 
E)  euglenids

Question 9

Which of the following move by cytoplasmic streaming?

Accepted Answer

A)  Euglenids 
B)  Plasmodial slime molds 
C)  Giardia lamblia, a diplomonad 
D)  Radiolarians 
E)  Toxoplasma, an apicomplexan 
A)  Euglenids 
B)  Plasmodial slime molds 
C)  Giardia lamblia, a diplomonad 
D)  Radiolarians 
E)  Toxoplasma, an apicomplexan

Question 10

_______ occurred when a dinoflagellate apparently lost its chloroplast and took up another protist that had acquired its chloroplast through secondary endosymbiosis.

Accepted Answer

A)  Primary endosymbiosis 
B)  Secondary endosymbiosis 
C)  Photosynthesis 
D)  Tertiary endosymbiosis 
E)  Asexual reproduction 
A)  Primary endosymbiosis 
B)  Secondary endosymbiosis 
C)  Photosynthesis 
D)  Tertiary endosymbiosis 
E)  Asexual reproduction

Question 11

The chloroplasts of green algae and land plants have two membranes.These chloroplasts were acquired through endocytosis of a cyanobacterium containing chlorophyll and possessing a double membrane.What two events would explain why the chloroplasts of euglenids (a unicellular clade) have three membranes yet contain the same photosynthetic pigments as both green algae and land plants?

Accepted Answer

A)  Plants arose from green algae and engulfed a euglenid to acquire photosynthetic pigments. 
B)  The ancestral euglenid engulfed a green alga through secondary endosymbiosis, while a different green alga became the ancestor to plants. 
C)  Ancestral green algae engulfed a euglenid through secondary endosymbiosis and gave rise to green plants. 
D)  Ancestral green plants arose from euglenids and then engulfed photosynthetic green algae. 
E)  Green plants engulfed a photosynthetic euglenid and were ancestral to green algae. 
A)  Plants arose from green algae and engulfed a euglenid to acquire photosynthetic pigments. 
B)  The ancestral euglenid engulfed a green alga through secondary endosymbiosis, while a different green alga became the ancestor to plants. 
C)  Ancestral green algae engulfed a euglenid through secondary endosymbiosis and gave rise to green plants. 
D)  Ancestral green plants arose from euglenids and then engulfed photosynthetic green algae. 
E)  Green plants engulfed a photosynthetic euglenid and were ancestral to green algae.

Question 12

Before Earth's atmosphere became rich in oxygen, early eukaryotes had little need for a _______ to detoxify O2.

Accepted Answer

Question 13

Peptidoglycan occurs between the chloroplast membranes of glaucophytes, the first eukaryote group to branch off following primary endosymbiosis.This is strong evidence that all chloroplasts arose from the engulfment of one cyanobacterium by a larger eukaryotic cell, because

Accepted Answer

A)  peptidoglycan is a photosynthetic pigment. 
B)  peptidoglycan occurs in the cell wall of bacteria. 
C)  eukaryotes produce peptidoglycan during phagocytosis. 
D)  prokaryotes produce peptidoglycan as a toxin against predators. 
E)  peptidoglycans were obtained by conjugation. 
A)  peptidoglycan is a photosynthetic pigment. 
B)  peptidoglycan occurs in the cell wall of bacteria. 
C)  eukaryotes produce peptidoglycan during phagocytosis. 
D)  prokaryotes produce peptidoglycan as a toxin against predators. 
E)  peptidoglycans were obtained by conjugation.

Question 14

The chloroplast of red algae retains certain pigments of the original cyanobacterial endosymbiont that are absent in the chloroplasts of green algae.The evolutionary significance of this is that

Accepted Answer

A)  red algae cannot photosynthesize, leading to heterotrophy. 
B)  neither green algae nor red algae can be classified as protists. 
C)  chloroplasts originated as free-living prokaryotes. 
D)  red algae are cyanobacteria. 
E)  red algae are prokaryotes. 
A)  red algae cannot photosynthesize, leading to heterotrophy. 
B)  neither green algae nor red algae can be classified as protists. 
C)  chloroplasts originated as free-living prokaryotes. 
D)  red algae are cyanobacteria. 
E)  red algae are prokaryotes.

Question 15

Which of the following is not used by aquatic protists for locomotion or flotation?

Accepted Answer

A)  Oil droplets 
B)  Pseudopods 
C)  Cilia 
D)  Flagella 
E)  Contractile vacuoles 
A)  Oil droplets 
B)  Pseudopods 
C)  Cilia 
D)  Flagella 
E)  Contractile vacuoles

Question 16

If you were to examine limestone deposits throughout the world, which group of organisms would you expect to find in the greatest abundance?

Accepted Answer

A)  Radiolarians 
B)  Dinoflagellates 
C)  Foraminiferans 
D)  Heliozoans 
E)  Oomycetes 
A)  Radiolarians 
B)  Dinoflagellates 
C)  Foraminiferans 
D)  Heliozoans 
E)  Oomycetes

Question 17

As cyanobacterial populations boomed, the process of photosynthesis generated significant levels of O2 in the oceans and atmosphere.Which statement accurately describes conditions surrounding the evolution of eukaryotes and the early role of the proteobacterial endosymbiont that would eventually develop into a mitochondrion?

Accepted Answer

A)  The increase in O2 resulted in an increase in the energy required to maintain the eukaryotic cell-the phagocytosis of a proteobacterium was originally intended as a form of food storage. 
B)  The increase in O2 resulted in a population boom for eukaryotes-those that enlisted the aid of a proteobacterial endosymbiont were more likely to find food sources than those that did not. 
C)  The increase in O2 had a reducing effect on most eukaryotes, and the acquisition of a proteobacterium that could reduce this O2 into water allowed the eukaryotic host to survive. 
D)  The increase in O2 had did not have an effect on most eukaryotes, but the acquisition of a proteobacterium that coupled O2 reduction with ATP production provided an additional source of energy to the eukaryotic host. 
E)  The increase in O2 had an oxidizing effect on most eukaryotes, and the acquisition of a proteobacterium that could reduce this O2 into water allowed the eukaryotic host to survive. 
A)  The increase in O2 resulted in an increase in the energy required to maintain the eukaryotic cell-the phagocytosis of a proteobacterium was originally intended as a form of food storage. 
B)  The increase in O2 resulted in a population boom for eukaryotes-those that enlisted the aid of a proteobacterial endosymbiont were more likely to find food sources than those that did not. 
C)  The increase in O2 had a reducing effect on most eukaryotes, and the acquisition of a proteobacterium that could reduce this O2 into water allowed the eukaryotic host to survive. 
D)  The increase in O2 had did not have an effect on most eukaryotes, but the acquisition of a proteobacterium that coupled O2 reduction with ATP production provided an additional source of energy to the eukaryotic host. 
E)  The increase in O2 had an oxidizing effect on most eukaryotes, and the acquisition of a proteobacterium that could reduce this O2 into water allowed the eukaryotic host to survive.

Question 18

If pollution were to destroy the majority of diatoms on Earth, the _______ in the atmosphere would likely increase, while the levels of O2 in the atmosphere would likely decrease.

Accepted Answer

Question 19

Fossil prokaryotes resemble modern rod-shaped bacteria.What appears to be a first step in the evolution of the modern eukaryote cell from a prokaryote ancestor?

Accepted Answer

A)  Formation of a nuclear envelope 
B)  Endosymbiosis resulting in acquisition of a mitochondrion 
C)  Loss of the stiff cell wall of bacteria 
D)  Development of organelles studded with ribosomes 
E)  Endosymbiosis resulting in acquisition of a chloroplast 
A)  Formation of a nuclear envelope 
B)  Endosymbiosis resulting in acquisition of a mitochondrion 
C)  Loss of the stiff cell wall of bacteria 
D)  Development of organelles studded with ribosomes 
E)  Endosymbiosis resulting in acquisition of a chloroplast

Question 20

Paramecia typically reproduce by dividing asexually, but they also have a sexual behavior called conjugation.Which of the following emphasizes the value of this sexual process for the survival of paramecia species?

Accepted Answer

A)  Conjugation is a form of reproduction that produces more diverse offspring than asexual reproduction. 
B)  Paramecia produced through conjugation contain multiple macronuclei, increasing their diversity. 
C)  Clonal lineages produced through conjugation contain multiple micronuclei, increasing the diversity within the clone. 
D)  In some species, without conjugation, clones die out after 350 cell divisions. 
E)  At the end of conjugation, each cell contains two haploid micronuclei, one of its own and one from the other cell. 
A)  Conjugation is a form of reproduction that produces more diverse offspring than asexual reproduction. 
B)  Paramecia produced through conjugation contain multiple macronuclei, increasing their diversity. 
C)  Clonal lineages produced through conjugation contain multiple micronuclei, increasing the diversity within the clone. 
D)  In some species, without conjugation, clones die out after 350 cell divisions. 
E)  At the end of conjugation, each cell contains two haploid micronuclei, one of its own and one from the other cell.

Exam 26: The Origin and Diversification of Eukaryotes

Perhaps the best-known _______ are the malarial parasites of the genus Plasmodium.

The ancestor of photosynthetic euglenids took up the chloroplast of a green alga.This explains why photosynthetic euglenids

Which statement about cellular slime molds is false?

Euglenids are single-celled freshwater organisms that move by using _______.

Hydrocarbons extracted from geological formations that are currently a source of petroleum were produced from the ancient buried remains of

Which term refers to a eukaryotic organism that undergoes alternation of generations in which different generations do not resemble each other morphologically?

Because silica resists compression, spiny remains of fossils of _______ can be used in "Earth-friendly" insecticides, to physically disrupt insect body functions in insects.

Which of the following move by cytoplasmic streaming?

_______ occurred when a dinoflagellate apparently lost its chloroplast and took up another protist that had acquired its chloroplast through secondary endosymbiosis.

Before Earth's atmosphere became rich in oxygen, early eukaryotes had little need for a _______ to detoxify O2.

Peptidoglycan occurs between the chloroplast membranes of glaucophytes, the first eukaryote group to branch off following primary endosymbiosis.This is strong evidence that all chloroplasts arose from the engulfment of one cyanobacterium by a larger eukaryotic cell, because

The chloroplast of red algae retains certain pigments of the original cyanobacterial endosymbiont that are absent in the chloroplasts of green algae.The evolutionary significance of this is that

Which of the following is not used by aquatic protists for locomotion or flotation?

If you were to examine limestone deposits throughout the world, which group of organisms would you expect to find in the greatest abundance?

If pollution were to destroy the majority of diatoms on Earth, the _______ in the atmosphere would likely increase, while the levels of O2 in the atmosphere would likely decrease.

Fossil prokaryotes resemble modern rod-shaped bacteria.What appears to be a first step in the evolution of the modern eukaryote cell from a prokaryote ancestor?

Paramecia typically reproduce by dividing asexually, but they also have a sexual behavior called conjugation.Which of the following emphasizes the value of this sexual process for the survival of paramecia species?

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

Filters

Before Earth's atmosphere became rich in oxygen, early eukaryotes had little need for a _______ to detoxify O₂.

If pollution were to destroy the majority of diatoms on Earth, the _______ in the atmosphere would likely increase, while the levels of O₂in the atmosphere would likely decrease.