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