Bio Module 5
What type of genome is characteristic of a coronavirus?
(+) sense single-stranded RNA
r plasmid
A bacterial plasmid carrying genes that confer resistance to certain antibiotics.
endoplasmic reticulum
A cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another.
protist
A eukaryotic organism that cannot be classified as an animal, plant, or fungus.
polymer
A long molecule consisting of many similar or identical monomers linked together.
temperate phage
A phage that is capable of reproducing by either the lytic or lysogenic cycle.
monomer
A simple compound whose molecules can join together to form polymers
The three modern monophyletic domains (Bacteria, Archaea, and Eukarya) evolved from?
A single primitive cell of the Archean eon
F plasmid replication and transfer
A single strand of the plasmid passes from the donor cell into the recipient cell and then a complementary strand is added by the recipient cell.
Virus
A small biological particle comprised of nucleic acid enclosed in a protein coat
plasmid
A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome a genetic structure in a cell that can replicate independently of the chromosomes, typically a small circular DNA strand in the cytoplasm of a bacterium or protozoan. Plasmids are much used in the laboratory manipulation of genes. Picture: it is a circle that is outside of the nucleiod DNA!
Golgi apparatus
A system of membranes that modifies and packages proteins for export by the cell
Endosymbiosis
A theorized process in which early eukaryotic cells were formed from simpler prokaryotes.
transposon
A transposable element that moves within a genome by means of a DNA intermediate.
peptidoglycan
A type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides. Cell wall of prokaryotes, but NOT ARCHAEA.
bacteriphage
A virus that infects bacteria
retrovirus
An RNA virus that reproduces by transcribing its RNA into DNA and then inserting the DNA into a cellular chromosome; an important class of cancer-causing viruses.
reverse transcriptase
An enzyme encoded by some certain viruses (retroviruses) that uses RNA as a template for DNA synthesis.
endoplasmic reticulum (ER)
An extensive membranous network in eukaryotic cells, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions.
Which of the following likely led to the evolution of eukaryotes from early prokaryotic organisms?
An increase in membrane flexibility, allowing for one cell to engulf another The loss of a rigid cell wall, allowing membranes to fold inward
Organisms that can produce all the organic carbon compounds they need to survive from CO2 are known as which of the following?
Autotrophs
Best definition of endosymbiotic bacteria?
Bacteria that live within other cells and perform specific functions for their host cells
Which of the following viruses uses the cellular machinery of a bacterium for its own replication?
Bacteriophage
chloroplasts
Capture energy from sunlight and use it to produce food for the cell
Of the following list, choose all that may be found in a viral particle
DNA RNA A protein shell An envelope
Viral genomes may be composed of ______ or ______ and may be ______ - stranded or _______-stranded.
DNA TNA Single Double
spongiform encephalopathy
Degenerative disease due to prion protein
How did mitochondria originate, according to the endosymbiotic theory?
Energy-producing bacteria were engulfed by larger bacteria and eventually evolved into mitochondria
A cell that has the F plasmid is designated as A) FF B) Fp C) F+ D) F-
F+
How do viruses replicate?
Host cells' transcription and translation systems are used to replicate the genome and create capsid proteins
During rolling-circle replication, as the F plasmid begins to replicate its DNA at the binding point, what happens to the displaced single strand of the plasmid?
It enters the recipient cell.
What is the E. coli fertility factor?
It is a plasmid, also known as the F plasmid. The fertility factor (first named F by one of its discoverers Esther Lederberg; also called the sex factor in E. coli or the F sex factor; also called F-plasmid) allows genes to be transferred from one bacterium carrying the factor to another bacterium lacking the factor by conjugation.
Bacteria in the family <i>Rhizobiaceae</i> form associations with ________plants; the bacteria live in specialized root _________ where they fix nitrogen for their hosts.
Leguminous, nodules
Peptidoglycan is an important component of the cell walls of which microbes?
Most bacteria
Which of the following may take place during bacteriophage reproduction after the phage genome is injected into the host cell?
New virus particles are synthesized by the cell and then released by lysis or budding The viral DNA is integrated into the genome of the host cell, allowing it to replicate when the host cell divides
For every single eukaryotic cell in the human body, there are roughly how many prokaryotic cells?
One prokaryotic cell
In the mutualistic symbiosis between bacteria in the family <i>Rhizobiaceae</i> and leguminous plants, how do the two organisms benefit?
Plants receive fixed nitrogen, while bacteria receive sugars.
What disease agents are infectious proteins that can cause transmissible spongiform encephalopathies?
Prions
rolling circle replication
Replication of circular DNA that is initiated by a break in one of the nucleotide strands, producing a double-stranded circular DNA molecule and a single-stranded linear DNA molecule, the latter of which may circularize and serve as a template for the synthesis of a complementary strand.
Which of the following are the three coronaviruses that cause moderate to serious disease in humans?
SARS-CoV SARS-CoV-2 MERS-CoV
Based on the latest data, the protists are divided into how many supergroups?
The Protists encompasses five supergroups, four of which contain parasites of human hosts: the Opisthokonta, the Amoebozoa, the Excavata, the Archaeplastida, and the SAR supergroups.
One of the major benefits of multicellularity is that it allows organisms to deal with their environments in novel ways through which of the following?
The specialization of cells into various types of tissues and organs
horizontal gene transfer
The transfer of genes from one genome to another through mechanisms such as transposable elements, plasmid exchange, viral activity, and perhaps fusions of different organisms. Horizontal gene transfer (HGT) is the movement of genetic information between organisms, a process that includes the spread of antibiotic resistance genes among bacteria (except for those from parent to offspring), fueling pathogen evolution.
What are the types of transduction?
There are two types of transduction: generalized and specialized. In generalized transduction, the bacteriophages can pick up any portion of the host's genome. In contrast, with specialized transduction, the bacteriophages pick up only specific portions of the host's DNA.
How does the replication of HIV proceed after it enters a host cell?
Viral RNA is a reverse-transcribed, incorporated into the host cell's DNA, and eventually used to produce many copies of the virus
Do viruses have parents?!
Viruses can reproduce only within a host cell. The parental virus (virion) gives rise to numerous progeny, usually genetically and structurally identical to the parent virus.
How is a eukaryote classified as a protist?
a eukaryote is classified as a protist when it cannot be classified in any other eukaryotic group
Viruses are unable to reproduce without....
a host cell
What type of prokaryote might have formed endosymbiotic relationships with other larger bacteria, eventually evolving into a chloroplast?
a photosynthetic bacterium (photosynthesis doesn't require chlorophyll!!)
polypeptides
a polymer of amino acids joined together by peptide bonds. (long chains)
transcriptase
a polymerase that catalyzes the formation of RNA from a DNA template in the process of transcription enzyme that reverse transcribes viral RNA to DNA
The genome of a mitochondrion is typically composed of which of the following?
a single, circular, closed molecule of DNA, similar to that in bacteria
Endosymbiotic
a smaller organism that lives within another organism, the theory of how eukaryotic cells were formed.
lytic cycle
a viral reproductive cycle in which copies of a virus are made within a host cell, which then bursts open, releasing new viruses
lysogenic cycle
a viral reproductive cycle in which the viral DNA is added to the host cell's DNA and is copied along with the host cell's DNA
What subdivides modern eukaryotic cells into many different functional compartments?
an extensive endomembrane system
Grazing animals cannot release glucose from cellulose in the plants they eat and rely on _______
anaerobic prokaryotes that can enzymaticallly digest glucose in their gut
Prokaryotes that obtain their energy from inorganic CO2 are _____ whereas those that require reduced forms of carbon (ie, organic molecules) are ____.
autotrophs, heterotrophs
Mitochondria and chloroplasts contain their own DNA which is very similar in size and character to the DNA of______
bacteria
In many mammals, intestinal microorganisms help with the digestion of ________
cellulose
Scientists hypothesize that photosynthetic bacteria were engulfed by other, larger cells and eventually evolved to become the organelles we now call________
chloroplasts
What are the three basic shapes of prokaryotes?
cocci (round), bacilli (rod), helical (spiral)
Once a pilus forms and connects a donor and a recipient cell, it is called a ____ ____.
conjugation brige
Chemical elements such as carbon, nitrogen, phosphorus, and sulfure are released from dead organisms back to the physical environment by prokaryotes and fungi that are called _____
decomposers
Modern eukaryotes appear to be most closely related to a group of
deep sea Archaea, known as Asgard
Infoldings of the prokaryotic plasma membrane are thought to have given rise to the eukaryotic endomembrane system that includes which of the following?
endoplasmic reticulum, and nuclear envelope
When a small cell is engulfed by a larger cell and eventually becomes part of the larger cell, it is called
endosymbiosis
Bacteria that live within other cells and perform specific functions for their host cells are called _______
endosymbiotic bacteria
Evolutionary mechanisms that were important in the early evolution of eukaryotes
engulfing other cells horizontal gene transfer
Prokaryotes ___ carbon from inorganic CO2 through the process of photosynthesis, allowing other organisms to use the organic compounds they produce
fix
The nucleus and the ER of eukaryotes are thought to have evolved _________
from the infoldings of the plasma membrane
When a phage with lytic life cycle packages a random bacterial DNA fragment instead of phage DNA and injects the bacterial DNA into another bacterial cell, this is referred to as which of the following?
generalized transduction
While prokaryotes do not reproduce sexually, DNA can be exchanged between different cells of the same species or between cells of different species. This is known as _______ gene transfer.
horizontal
encephalopathies
infections that affect the cortex of the brain
In eukaryotic cells, the Golgi apparatus and the endoplasmic reticulum facilitate
intracellular transport and localization of proteins to specific cellular regions
What are some important roles of the gut microbiome in humans?
it is involved in the digestion of complex carbohydrates it is involved in the synthesis of essential amino acids
SARS-CoV-2 infections are quite variable, with some being asymptomatic, some resulting in mild symptoms, and some resulting in severe symptoms and death. Which of the following are characteristic of severe cases?
kidney failure pneumonia acute respiratory distress
nuclear envelope
layer of two membranes that surrounds the nucleus of a cell
According to the endosymbiotic theory, non-photosynthetic, energy-producing bacteria were engulfed by larger bacteria and evolved into the organelles called________
mitochondria
Protists that are both phototrphic and heterotrophic are called
mixotrophic
A major advantage of ________is that it enables cells to specialize into tissues and organs having specific functions
multicellularity
phototrophic
organisms which use light as an energy source for production of organic molecules.
The cell walls of most bacteria contain a polymer called
peptidoglycan
trophic
pertaining to development
Some prokaryotes are able to fix carbon from inorganic CO2 through the process of ______.
photosynthesis
A small, independently replicating circle of DNA that is found in many prokaryotic cells and contains a small number of genes, that may confer advantage to the cell in certain conditions, is called a ________.
plasmid
Organisms in the domains Bacteria and Archaea are collectively referred to as
prokaryotes
Which of the following are the most abundant organisms on Earth?
prokaryotes
The first eukaryotes
protists
Based on the nature of its genome and the way it is replicated, HIV is an example of A) a DNA virus B) a poxvirus C) a herpesvirus D) a retrovirus
retroviurs
Once it enters the cytoplasm of a host cell, replication of HIV begins when ________ ________ is used to synthesize a double strand of DNA from the viral RNA.
reverse transcriptase
Many animals, such as cows, have a specialized digestive organ called the __________, inside of which anaerobic bacteria digest cellulose.
rumen
mini-chromosomes
small chromosome-like DNA-protein structures that sometimes form in different types of eukaryotic cells
vesicles
small membrane sacs that specialize in moving products into, out of, and within a cell
A ________ phage is one that can enter either a lysogenic or a lytic cycle
temperate
Transmissible spongiform encephalopathies (TSEs) cause
the development of numerous small cavities in the brain as neurons die
The loss of the rigid cell wall and an increase in membrane flexibility were key evolutionary events that likely led to the evolution of _______.
the first eukaryotes
invagination
the folding in of a membrane or layer of tissue so that an outer surface becomes an inner surface
Natural ___________ occurs when a cell dies and releases its contents into the surrounding environment and DNA fragments are taken up by other living cells.
tranformation Cool explanation: https://www.quora.com/Can-horizontal-gene-transfer-occur-between-a-living-cell-and-a-dead-cell-Could-a-dead-cell-pass-on-its-genes-to-a-living-cell
The disease that causes the development of numerous small cavities in the brain of infected individuals due to death of neurons, producing a spongy appearance, is called Blank______.
transmissible spongiform encephalopathy
Unlike horizontal gene transfer, ____ gene transfer occurs when genes are passed from one generation to the next.
vertical
endo
within
