Biology 1120 Exam 2
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.
Which structure acts like a motor for the bacterial flagellum?
basal body
Which disease is caused by an exotoxin released by the gram-positive, endospore-forming bacteria, often because food was not heated sufficiently to kill the endospores?
botulism
What is the protein coat of a virus called?
capsid
Which protist group contains the organism Trypanosoma, a colorless parasite that can cause African sleeping sickness?
excavates
Peptidoglycan consists of:
sugars crosslinked with proteins
A bryophyte having a single large chloroplast in each cell belongs to which phylum?
Anthocerophyta
How are viruses classified by the ICTV?
By their host range and other characteristics
Members of which group are known to form blooms known as red tides?
dinoflagellates
Which protist groups consists of individuals who often have intracellular shells of interlocking plates?
dinoflagellates
What are the viruses that attack bacteria?
phages
Most conifers have separate male and female reproductive parts on the same tree. This condition is referred to as:
monoecious
In plants, the fertilized egg develops into a multicellular ____ (young plant) within a female gametangium.
embryo
The five stages of a lytic infection are attachment, penetration, __________, assembly, and release.
replication
Angiosperms have ____ in their phloem.
sieve tube elements
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 hypothesis asserts that viruses are remnants of cellular organisms and evolved from small cells that were parasites in larger cells?
regressive hypothesis
The genome of most plant viruses consists of what kind of RNA?
ssRNA
____ are small leaves with a single vascular strand.
Microphylls
What commercial product is derived from the processing of red algae?
carrageenan
Which protist group is characterized by having a micronucleus and a macronucleus?
ciliates
Bacterial ____ cause systemic symptoms such as fever, whereas bacterial ____ cause more specific maladies.
endotoxins; exotoxins
Members of which protist group is one of the fossilized deposits in the unique geological formation of the White Cliffs of Dover?
foraminiferans
What are the multicellular sex organs in plants?
gametangia
Some liverworts reproduce asexually by forming tiny balls of tissue called:
gemmae
Which group of protists are unicellular, biflagellate stramenopiles that forms a significant portion of the nanoplankton?
golden algae
Streptococci, the bacteria responsible for strep throat infections, is classified within which group of Bacteria?
gram-negative
The ____ generation is dominant in mosses, as it can live independently.
haploid gametophyte
Brown algae lack true roots, but have similar structures called ____ that anchor them to the substrate.
holdfasts
Cows and other ruminates rely on a ____ relationship with bacteria in their digestive tract.
mutualistic
What type of bacterium would not be able to survive in the presence of oxygen?
obligate anaerobic
What is an example of an economically important basal angiosperm?
star anise
Viroids cause a variety of plant diseases and are composed only of:
strands of RNA
Although bacteria lack membrane-bound organelles, such as chloroplasts and mitochondria, they can still perform the functions of these organelles by localizing certain metabolic enzymes on:
the plasma membrane
Some bacteria avoid being phagocytized by a host's immune system by means of:
their capsule or slime layer
Which are the symbiotic dinoflagellates, which live in the bodies of marine invertebrates such as corals?
zooxanthellae
Extracts from the ginkgo tree are sold in over the counter (OTC) medicines purported to increase memory. Extracts from what other gymnosperm were once sold in OTC weight loss supplements?
ephedra
The Archaea plasma membranes are made up of branched-chain hydrocarbons bounded to glycerol by:
ether linkages
Which eukaryotic organelles likely arose from symbiotic relationships between larger cells and bacteria?
mitochondria and chloroplasts
A plant with parallel veins and floral parts in threes or multiples of three would be classified as a:
monocot
What type of leaf venation do eudicots possess?
netted
The first plants to produce seeds evolved during which time period?
Devonian period
How do some bacteria respond to adverse environmental conditions?
by forming endospores
Recent studies of gene function as it relates to reproductive development suggest that angiosperms evolved most directly from:
conifers
____ is a form of genetic exchange in bacteria that involves contact between two cells.
conjugation
What type of conversion occurs when a bacterium carrying viral genes takes on new, atypical characteristics?
lysogenic
Coralline forms of which group of protists are ecologically important in the formation of coral reefs?
red algae
Microphylls is a structure that can only be found in:
club moss
In a flowering plant, the ____ is the site of meiosis and, ultimately, the production of pollen.
anther
In the process of fertilization in conifers, the pollen tube grows to which structure?
archegonium
At what stage of a lytic infection are phage components put together to make new viruses?
assembly
The most common mode of reproduction in bacteria is:
binary fission
According to the progressive hypothesis, viruses may have originated as mobile genetic elements such as:
plasmids
What are Koch's postulates?
A set of guidelines to demonstrate that a specific pathogen causes specific disease symptoms
describe the composition of cell walls found in water molds
Some individuals have cell walls of chitin, and others have cell walls of cellulose
Who is credited with the discovery of prions as a new biological principle of infection?
Stanley Prusiner
What is the purpose of sex pili?
To transmit DNA between bacteria
A bacterium that uses the oxidation of inorganic compounds to provide energy for manufacturing nutritious organic compounds is a:
chemoautotroph
Where would you likely find Euryarchaeota bacteria?
cow digestive tracts
Human viruses can enter human cells by fusion with the cell membrane or by:
endocytosis
Small hairlike structures made up of protein on the surface of bacteria are called:
fimbriae
What do the large female cones of a pine tree contain?
megasporangia
Microsporocytes divide by ____ to form ____.
meiosis; microspores
The volume of a typical bacterium is about _____ the volume of a typical eukaryotic cell.
one thousandth
The female gametophyte generation in angiosperms is found in the:
ovule of the ovary.
Viral infections in humans spread via the circulatory system. Viral infections in plants spread from cell to cell via:
plasmodesmata
Which protist group are characterized by a multinucleate amoeboid-like feeding form?
plasmodial slime molds
The oldest known megafossils of early vascular plants may be characterized as:
possessing dichotomously branched stems without leaves or roots
Mad cow disease is an example of an infection caused by a:
prion
Gram-positive bacteria would stain _(color)___ in a gram stain because of a thick layer of ____ in their cell walls.
purple; peptidoglycan
The specificity of viruses to different types of cells is due to ____ sites on the host cell.
receptor
Which two plants of the Carboniferous period contributed to the formation of today's coal deposits?
horsetails and club mosses
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.
If you identify a plant as Magnolia grandiflora, you therefore conclude that this plant is:
a core angiosperm
The most significant difference between archaea and bacteria is the:
absence of peptidoglycans in the cell walls of archaea
The most diverse, successful, and familiar group of plants today are the:
angiosperms
most protists are:
aquatic
The bacterium that causes botulism disease is harmless until it:
contains a certain prophage DNA
What is a symptom of a transmissible spongiform encephalopathy (TSE)?
degeneration of the brain and central nervous system
Cycads may be characterized as being:
dioecious and having motile sperm
In flowering plants, the ____ generation is dominant.
diploid sporophyte
The leafy fern that you might have as a house plant is the ____ generation.
diploid sporophyte
Which protist group typically moves with two or more flagella?
diplomonads
In most developing eudicot seeds, the primary source of nutritive material is in the:
endosperm
The oldest known fossils suggest that the ____ may have been the first plants to inhabit land.
liverworts
Progymnosperms had two derived features, which are:
megaphylls and woody tissue
What is the correct unit of measurement for the size of most viruses?
nanometers
Given the diversity in protist ultrastructure and molecular data, biologists regard the protists as a(n) ____ group, meaning that some are descendants of a common eukaryote ancestor.
paraphyletic
polydnaviruses have an unusual characteristic in that...
their circular DNA does not have genes for making the proteins needed to replicate and produce new viruses
How do bacteria move?
By means of a rotating flagella
Which phylum has very few surviving species, and are tropical and subtropical plants with stout, trunk-like stems, and compound leaves that resemble those of palms or tree ferns?
Cycadophyta
Which is a basic difference between gymnosperms and flowering plants?
Gymnosperms produce seeds borne naked, while flowering plants produce seeds enclosed within a fruit.
The fertilization process of flowering plants involves ____ nuclear fusion(s).
2
Which was the first bacterium to be clearly identified as the cause of an infectious disease?
Bacillus anthracis, which causes anthrax
The ____ classification system classifies viruses based on the type of nucleic acid the virus contains.
Baltimore
Flowering plants appeared in the fossil record in the:
Jurassic and Lower Cretaceous periods.
Which algal group contains individuals that are typically unicellular and form siliceous shells?
diatoms
The first plants evolved rapidly during which time period?
silurian
After sexual reproduction in a moss, the ____ grows out of the gametophyte.
sporophyte
Which is the gametophyte form of most liverworts?
thallus
What do the xylem and phloem make up of in a plant?
vascular tissue
Which of the following identifies a group of RNA viruses?
Paramyxoviruses
You find a protist that has a single flagellum surrounded by a collar of microvilli. You correctly conclude that this organism is a(n):
cellular slime mold.
Members of the alveolates are characterized by the presence of:
flattened vesicles under the plasma membrane