bio ch 24, 25, 26
true or false: Amoebozoans move by means of "flagella."
False- pseudopodia
Satellite=
Subviral agents that require a helper virus to reproduce.
Conjugation=
(1) A sexual process in ciliate protists that involves exchange of haploid nuclei with another cell. (2) A mechanism for DNA exchange in bacteria that involves cell-to- cell contact.
Capsule=
(1) The portion of the moss sporophyte that contains spores. (2) A simple, dry, dehiscent fruit that develops from two or more fused carpels and opens along many sutures or pores to release seeds. (3) A gelatinous coat that surrounds some bacteria.
Which structure of the virus in the accompanying figure is the capsid?
2
Members of the ____ move via pseudopodia.
Amoebozoa
Which protist group contains the organism Trypanosoma, a colorless parasite that can cause African sleeping sickness?
excavates
According to the progressive hypothesis, viruses may have originated as mobile geneticelements such as:
plasmids
What are the small circles of DNA that exist within the bacterial cytoplasm in addition to the bacterial chromosome?
plasmids
Viral infections in humans spread via the circulatory system. Viral infections in plants spread from cell to cell via:
plasmodesmata
Which of the following diseases is a DNA virus?
smallpox
Viroids cause a variety of plant diseases and are composed only of:
strands of RNA.
Plasmids of bacteria often have genes involved in:
antibiotic resistance.
Which protist groups consists of individuals who often have intracellular shells of interlocking plates?
dinoflagellates
A bacterium that uses the oxidation of inorganic compounds to provide energy for manufacturing nutritious organic compounds is a:
chemoautotroph
The surface of a Paramecium is covered with thousands of short, hair-like ____.
cilia
Members of the ____ are thought to have given rise to plants.
green algae
Temperate=
integrate their nucleic acid into the DNA of their bacterial host.
Which is an anaerobic excavate that is an endosymbiont of animals?
parabasilid
Human viruses can enter human cells by fusion with the cell membrane or by:
endocytosis.
The Archaea plasma membranes are made up of branched-chain hydrocarbons bounded to glycerol by:
ether linkages.
Streptococci, the bacteria responsible for strep throat infections, is classified within which group of Bacteria?
gram-negative bacteria
Which protist group does not have flagellated cells?
red algae
The five stages of a lytic infection are attachment, penetration, __________, assembly, and release.
replication
Which statement about bacteria is FALSE?
Bacteria are not cellular and are sometimes not classified as life forms.
true or false: Red tides are caused by "red algae".
False - dinoflagellates
Excavates=
Flagellated unicellular protists, many of which have a deep (excavated) oral groove; include diplomonds, parabasilids, and euglenoids.
How do retroviruses differ from other RNA viruses?
Retroviruses have reverse transcriptase instead of RNA-dependent RNA polymerase.
Mad cow disease is an example of an infection caused by a:
prion
Lactic-acid bacteria are used for:
producing sauerkraut.
Gram-positive bacteria would stain ____ in a gram stain because of a thick layer of ____ in their cell walls.
purple; peptidoglycan
What is a chain of round bacteria called?
streptococci
true or false: Foraminiferans are "Rhizarians."
true
true or false: The body of a water mold is called a(n) "mycelium."
true
Who is credited with the discovery of prions as a new biological principle of infection?
Stanley Prusiner
Mycelium=
The vegetative body of most fungi and certain protists (water molds); consists of a branched network of hyphae.
Most bacterial cells can keep from bursting in a hypotonic environment because of:
a rigid cell wall
Small hairlike structures made up of protein on the surface of bacteria are called:
fimbriae
Members of the alveolates are characterized by the presence of:
flattened vesicles under the plasma membrane.
What are the viruses that attack bacteria?
phages
Viral proteins can damage host cells by which process?
overwhelming the host cell with a large number of viruses.
Most protists are:
aquatic
Which of the following are rod-shaped bacteria?
bacilli
Flagellum=
A long, whiplike structure extending from certain cells and used in locomotion. (1) Eukaryote flagella consist of two central, single microtubules surrounded by nine double microtubules (9 + 2 structure), all covered by a plasma membrane. (2) Bacterial flagella are filaments rotated by special structures located in the plasma membrane and cell wall. (3) Archaea have a rotating appendage, an archaellum, for motility.
Foraminifera=
A marine protist that produces a shell, or test, that encloses an amoeboid body
Prion=
An infectious agent that consists only of protein.
Pathogen=
An organism, usually a microorganism, capable of producing disease
How do bacteria move?
By means of a rotating flagella
____ is a form of genetic exchange in bacteria that involves contact between two cells.
Conjugation
Axopods=
Long, filamentous, cytoplasmic projections characteristic of actinopods.
Capsid=
Protein coat surrounding the nucleic acid of a virus.
Holdfast=
The basal structure for attachment to solid surfaces found in multicellular algae.
Lysogenic conversion=
The change in properties of bacteria that results from the presence of a prophage.
Sporozite=
The infective sporelike state in apicomplexans
Which statement about viruses is FALSE?
Viruses can manufacture proteins.
Which characteristic defines a virus?
Viruses cannot metabolize.
Which type of protist is responsible for malaria in humans, parasitic to both humans and mosquitoes?
apicomplexans
What is the protein coat of a virus called?
capsid
Which protist group is characterized by having a micronucleus and a macronucleus?
ciliates
In primary endosymbiosis, an ancient eukaryotic cell engulfed a(n) ____, which survived and evolved into a chloroplast.
cyanobacterium
What is the nutritional mode of most bacteria?
heterotrophy
Brown algae lack true roots, but have similar structures called ____ that anchor them to the substrate.
holdfasts
Virulent=
kill their host cell during each cycle of infection.
Which eukaryotic organelles likely arose from symbiotic relationships between larger cells and bacteria?
mitochondria and chloroplasts
The most significant difference between archaea and bacteria is the:
absence of peptidoglycans in the cell walls of archaea.
Where would you likely find Euryarchaeota bacteria?
cow digestive tracts
Transduction=
(1) The transfer of a genetic fragment from one cell to another (e.g., from one bacterium to another) by a virus. (2) In the nervous system, the conversion of energy of a stimulus to electrical signals.
Ancestors of ____ may have possessed mitochondria, which were lost or reduced during evolutionary history.
Giardia
What is a prophage?
It is phage DNA that is integrated into bacterial DNA.
Which protist is responsible for late blight of potatoes, the cause of the Irish potato famine in the mid 19th century?
Phytophthora
The bacterium that causes botulism disease is harmless until it:
contains a certain prophage DNA.
Which is a symptom of a transmissible spongiform encephalopathy (TSE)?
degeneration of the brain and central nervous system
Which are the symbiotic dinoflagellates, which live in the bodies of marine invertebrates such as corals?
zooxanthellae
Plasmodium=
A multinucleate mass of living matter that moves and feeds in an amoeboid fashion.
What are Koch's postulates?
A set of guidelines to demonstrate that a specific pathogen causes specific disease symptoms
Viroid=
A tiny, naked, infectious particle consisting only of nucleic acid.
Which statement describes a virulent phage?
A virulent phage destroys bacteria
F factor=
Donor cells (F+ cells) have a DNA sequence (F factor) that allows them to transmit DNA to recipient cells (F− cells) by conjugation
Plankton=
Free-floating, mainly microscopic aquatic organisms found in the upper layers of the water; consisting of phytoplankton and zooplankton.
Plasmid=
Small, circular, double- stranded DNA molecule that carries genes separate from those in the main DNA of a cell.
I am characterized by having a test and axopods. Who am I?
actinopods
Before an animal cell's membrane fuses with a virus, the virus must first:
attach to a specific receptor on the plasma membrane of the host cell.
The most common mode of reproduction in bacteria is:
binary fission.
Which structure in the accompanying figure is labeled as C?
capsule
What commercial product is derived from the processing of red algae?
carrageenan
Envelop=
pick up a fragment of host plasma membrane as they leave the infected cell
Bacillus=
rod shaped bacterium
Peptidoglycan consists of:
sugars crosslinked with proteins
Most protists are ____, with each cell forming a complete organism capable of performing all the functions characteristic of life.
unicellular