Module 9

A bacterium that uses the oxidation of inorganic compounds to provide energy for manufacturing nutritious organic compounds is a:

chemoautotroph

The stramenopiles include water molds, diatoms, golden algae, and brown algae.

True

Which structure acts like a motor for the bacterial flagellum?

Basal body

How are viruses classified by the ICTV?

By their host range and other characteristics

An emerging virus is one that is not new to a population or that is rapidly increasing in incidence.

False

What does ssDNA stand for?

single stranded DNA

Togaviruses

ssRNA that can serve as mRNA ; enveloped viruses

Orthomyxoviruses

ssRNA that serves as template for mRNA synthesis; medium sized enveloped that often exhibit projecting spikes

Viroids cause a variety of plant diseases and are composed only of:

strands of RNA.

Which of the following typically occurs all at once and results in rapid cell lysis?

Phage release

Most protists are:

aquatic

Forams and actinopods

Rhizarians

The most common mode of reproduction in bacteria is:

binary fission.

Some protists consist of a single cell with multiple nuclei. This condition is known as:

coenocytic.

Members of the alveolates are characterized by the presence of:

flattened vesicles under the plasma membrane.

Amoebozoans and opisthokonts

Unikonts

Prokaryotes divide using a process called________.

binary fission

____________ are the largest and most complex of all algae.

brown algae

The bacterium that causes botulism disease is harmless until it:

contains a certain prophage DNA.

Actinopods are mostly marine plankton rhizarians with long, filamentous cytoplasmic projections called __________.

axopods

What are the viruses that attack bacteria?

phages

Crenarchaeota are also called:

sulfur bacteria.

Which statement about biofilms is FALSE?

Biofilms are usually less than 2 μm thick.

Which statement about radiolarians is FALSE?

They lack silica shells.

Botox is the marketed version of the botulism exotoxin, used to treat muscle spasms and for cosmetic purposes.

True

Where would you likely find Euryarchaeota bacteria?

Cow digestive tracts

What is the translation of "pseudopodia," a characteristic of the amoebas?

False feet

Which group of protists are unicellular, biflagellate stramenopiles that form a significant portion of the nanoplankton?

Golden algae

Small hairlike structures made up of protein on the surface of bacteria are called:

fimbriae

Which of the following is the most common structure of a virus?

Icosahedron

Which of the following are RNA viruses that have a DNA polymerase?

Retroviruses

_______________ are those that have been almost eradicated and then suddenly recur, causing an epidemic.

Re-emerging viruses

Which statement about viruses is FALSE?

Viruses can manufacture proteins.

_________ secrete many-chambered tests with pores through which cytoplasmic projections extend to move and obtain food.

Forams

At what stage of the lysogenic cycle would a prophage appear?

Integration

Dinoflagellates and water molds

Chromalveolates

How do retroviruses differ from other RNA viruses?

Retroviruses have reverse transcriptase instead of RNA-dependent RNA polymerase.

How do bacteria move?

By means of a rotating flagella

Cellular slime molds and choanoflagellates

Unikonts

Mycoplasma

Lack cell walls

Humans have __________ pairs of chromosomes.

23

Which statement describes a virulent phage?

A virulent phage destroys bacteria.

Which type of protist is responsible for malaria in humans, parasitic to both humans and mosquitoes?

Apicomplexans

Cyanobacteria

Contain chlorophyll

Mycobacteria

Contain waxy cell wall

You find a unicellular organism that forms lobe-like pseudopodia. When you expose the cells to cAMP, they aggregate into a slug like structure. Based on this information, you correctly conclude that this organism is known as:

Dictyostelium discoideum.

Which protist groups consists of individuals who often have intracellular shells of interlocking plates?

Dinoflagellates

Diplomonads and euglenoids

Excavates

Which statement describes a temperate virus?

A temperate virus does not always destroy its host.

The genome of most plant viruses consists of what kind of RNA?

ssRNA

Chlamydia

Lack peptidoglycan cell walls

Which eukaryotic organelles likely arose from symbiotic relationships between larger cells and bacteria?

Mitochondria and chloroplasts

Which protist clade (supergroup) is characterized by their greatly modified mitochondria?

Excavates

Which Archaea have the ability to carry out a form of the Calvin cycle, capturing sunlight with bacteriorhodopsin?

Extreme halophiles

Parabasilids are excavates that lack functional mitochondria and lack a Golgi complex.

False

Members of which protist group is one of the fossilized deposits in the unique geological formation of the White Cliffs of Dover?

Foraminiferans

Ancestors of ____ may have possessed mitochondria, which were lost or reduced during evolutionary history.

Giardia

Of the following, which group exhibits a diverse morphology, forming unicells, filaments, and sheets?

Green algae

What are the small circles of DNA that exist within the bacterial cytoplasm in addition to the bacterial chromosome?

Plasmids

Coralline forms of which group of protists are ecologically important in the formation of coral reefs?

Red algae

Herpesviruses

dsDNA: large complex enveloped virus; replicates in host nucleus

Papovaviruses

dsDNA: nonenveloped virus

The Archaea plasma membranes are made up of branched-chain hydrocarbons bounded to glycerol by:

ether linkages.

Unikonts also have a ____________ that has major evolutionary significance.

triple-gene fusion

Sexual reproduction can be grouped into how many distinct stages?

3

Which of the following statements is correct in the context of golden algae?

Are mostly unicellular, biflagellate freshwater and marine stramenopiles

Who is credited with the discovery of prions as a new biological principle of infection?

Stanley Prusiner

What commercial product is derived from the processing of red algae?

Carrageenan

___________ are amoebozoa with close affinities to amoebas and plasmodial slime molds.

Cellular slime molds

Alveolates and stramenopiles

Chromalveolates

Which algal group contains individuals that are typically unicellular and form siliceous shells?

Diatoms

Among the protist groups below, which has organisms that typically move with two or more flagella?

Diplomonads

Trypanosomes and parabasalids

Excavates

Which protist is responsible for late blight of potatoes, the cause of the Irish potato famine in the mid-19th century?

Phytophthora

Which statement about euglenoids is FALSE?

They have a pellicle

Bacterial conjugation is related to____________.

horizontal gene transfer

How do some bacteria respond to adverse environmental conditions?

Bacteria form endospores.

Within ciliates, what do the micronuclei control?

Reproduction

Actinomycetes

Resemble fungi

Which are the symbiotic dinoflagellates, which live in the bodies of marine invertebrates such as corals?

Zooxanthellae

Plasmids of bacteria often have genes involved in:

antibiotic resistance

Pseudopodia are used by Amoeba for ingesting food as well as for:

locomotion.

Lactic-acid bacteria are used for:

producing sauerkraut.

Retroviruses

ssRNA enveloped viruses; contains reverse transcriptase for transcription of RNA into DNA; two identical molecules ssRNA

Peptidoglycan consists of:

sugars crosslinked with proteins

Some bacteria avoid being phagocytized by a host's immune system by means of:

their capsule or slime layer.

Cells that have a single flagellum or are amoebas with no flagella are _________.

unikonts

What is commensalism?

A relationship between individuals of two species in which one benefits and the other derives neither benefit nor harm

Red algae and green algae

Archaeplastids

Which statement about bacteria is TRUE?

Bacteria are cellular and are sometimes classified as life forms.

Red tides are caused by red algae.

False

The nucleic acid core of the virus is not surrounded by a protein coat called a capsid.

False

Which of the following is true for exotoxins?

The effect on the host is similar for all.

Conjugation is the process by which one bacterium transfers genetic material to another through direct contact.

True

Genomic deoxyribonucleic acid is chromosomal DNA.

True

Horizontal gene transfer greatly contributes to the rapid evolution that takes place in prokaryotes.

True

Lytic reproductive cycles destroy host cells.

True

The dense cytoplasm of the prokaryote contains ribosomes and storage granules.

True

The immunodeficiency virus that causes acquired immunodeficiency syndrome is an enveloped virus.

True

Which statement about bioremediation is FALSE?

Very few species of bacteria are used to clean up various forms of pollution.

Why is penicillin ineffective against gram-negative bacteria?

Penicillin cannot reach the thin peptidoglycan layer easily because it is protected by the bacteria's outer membrane.

Which protist group are characterized by a multinucleate amoeboid-like feeding form?

Plasmodial slime molds

Which has an unusual characteristic in that their circular DNA does not have genes for making the proteins needed to replicate and produce new viruses?

Polydnaviruses

Many green algae produce spores asexually by mitosis; if these spores have flagella and are motile, they are called __________.

zoopores

What is the protein coat of a virus called?

Capsid

Viral proteins can damage host cells by which process?

Overwhelming the host cell with a large number of viruses

What are subviral agents that depend on co-infection of a host cell with a helper virus?

Satellites

What is the purpose of phage therapy?

To target specific bacteria in the body and destroy them

Which characteristic defines a virus?

viruses cannot metabolize

Which of the following is NOT part of the Chromalveolates group of eukaryotes?

Euglenoids

Which protist group possess a crystalline rod in their flagella?

Euglenoids

Bacteria protect themselves from bacteriophage infections by producing restriction enzymes that cut up foreign RNA of the phage.

False

Bacteriophages attach to the cell walls of bacteria by envelope proteins.

False

Coccolithophorids are marine members of the brown algae.

False

Gram-negative cell walls have an outer membrane that contains lipids and peptidoglycans.

False