BMED 1106 midterm review
oxygenation of the atmosphere
Which characteristic is shared by prokaryotes and eukaryotes?
DNA based genome
Mitochondria most likely evolved by
endosymbiosis
which of these protists is believed to have evolved following a secondary endosymbiosis
chlorarachniophytes
In 2016, scientists published the genome of Monocercomonoides, and demonstrated that this organism has no detectable mitochondrial genes. However, its genome was arranged in linear chromosomes wrapped around histones which are contained within the nucleus. Monocercomonoides is therefore a(n) _
Eukaryote
Which of the following observations about a bacterium would distinguish it from the last eukaryotic common ancestor
lack of membrane bound structure surrounding the genome
protists that have a pellicle are surrounded by _________.
proteins
Protists with the capabilities to perform photosynthesis and to absorb nutrients from dead organisms are called
saprobes
Which of these locomotor organs would likely be the shortest?
cilium
Alternation of generations describes which of the following
both haploid and diploid forms are muticellular
The amoeba E. histolytica is a pathogen that forms liver abscesses in infected individuals. Its metabolic classification is most likely ______.
anaerobic heterotroph
Which protist group exhibits mitochondrial remnants with reduced functionality?
parabasilids
Conjugation between two Paramecia produces ________ total daughter cells.
8
what is the function of the raphe in diatoms?
locomotion
What genus of protists appears to contradict the statement that unicellular restricts cell size
Caulerpa
An example of carbon fixation is ____
photosynthesis
Which parasitic protist evades the host immune system by altering its surface proteins with each generation
Trypanosoma brucei
which of the following is not a way that protists contribute to the food web
they occupy the apex producer niche
A marine biologist analyzing water samples notices a protist with a calcium carbonate shell that moves by pseudopodia extension. The protist is likely to be closely related to which species?
ammonia tepida
Which polysaccharide is usually found in the cell wall of fungi
chitin
Which of these organelles is not found in a fungal cell
chloroplast
The wall dividing individual cell in a fungal filament is called a
septum
During sexual reproduction, a homothallic mycelium contains
both mating types
The life cycles of perfect fungi are most similar to which another organism
haploid dominant green algae
The most primitive phylum of fungi is the ___________.
Chytridiomycota
Members of which phylum establishes a successful symbiotic relationship with the roots of trees.
glomeromycota
Members of which phylum produce a clubshaped structure that contains spores
basidiomycota
The fungi that do not reproduce sexually used to be classified as
deuteromycota
A scientist discovers a new species of fungus that introduces genetic diversity during reproduction by creating a diploid zygote. This new species cannot belong to which modern phylum of fungi
deuteromycota
What term described the close association of fungus with the root of tree
a mycorrhiza
why are fungi important decomposers?
they recycle carbon and inorganic minerals by the process of decomposition
Consider an ecosystem where all the fungi not involved in mycorrhizae are eliminated. How would this affect nitrogen intake by plants?
nitrogen intake would decrease
A fungal infection that affects nails and skin is classified as
systemic mycosis
A fungus that climbs up a tree reaching higher elevation to release its spores in the wind and does not receive any nutrients from the tree or contribute to the tree’s welfare is described as a
commensal
The targets for anti-fungal drugs are much more limited than antibiotics or anti-viral medications. Why?
human cells are much more similar to fungi than bacteria or viruses
Yeast is a facultative anaerobe. This means that alcohol fermentation takes place only if
the atmosphere does not contain oxygen
The advantage of yeast cells over bacterial cells to express human proteins is that
yeast cells are eukaryotic and modify proteins similar to human cells
Why are fungal insecticides an attractive alternative to chemical pesticides for growing food crops
Human consumption of fungal insecticides would not make a person sick, but ingestion of chemical pesticides can be harmful to humans
The first forms of life on Earth were though to be the _________________
prokaryotes
Microbial mats _______
all of the above
The first organisms that oxygenated the atmosphere were
cyanobacteria
Halophiles are organisms that require _______.
a salt concentration of at least 0.2M
Many of the first prokaryotes to be cultured in a scientific lab were human or animal pathogens. Why would these species be more readily cultured than non-pathogenic prokaryotes?
most of the necessary culture conditions could be inferred for pathogenic prokaryotes
The presence of a membrane-enclosed nucleus is a characteristic of ______________.
eukaryotic cells
Which of the following consist of prokaryotic cells
bacteria and archaea
The cell wall is ________.
exterior to the cell membrane
Organisms most likely to be found in extreme environments are
archaea
Prokaryotes stain as gram-positive or gram negative because of differences in the cell
wall
Pseudopeptidoglycan is a characteristic of the walls of ________.
Archaean prokaryotic cells
The lipopolysaccharide layer (LPS) is a characteristic of the wall of
Gram negative bacteria
Which of the following elements is not a micronutrient
boron
Prokaryotes that obtain their energy from chemical compounds are called
chemotrophs
Ammonification is the process by which __________.
ammonia is releases during the decomposition of nitrogen containing organic compounds
Plants use carbon dioxide from the air and are therefore called
producers
cyanobacteria harness energy from the sun through photosynthesis and oxidize water to provide electrons for energy generation. Thus, we classify cyanobacteria as
photoautotrophs
A disease that is constantly present in a population is called
endemic
Which of the statements about biofilms is incorrect
biofilms are considered responsible for diseases such as cystic fibrosis.
Which of these statements is true
. an antibiotic is any substance produced by a organism that is antagonistic to the growth of the prokaryotes
A person in England arrives at a medical clinic with a fever and swollen lymph nodes shortly after returning from a visit to New Mexico. For which bacteria should the doctor test the patient?
Salmonella enterica
In addition to providing yogurt its unique flavor and texture, lactic acid-producing bacteria also provide which additional benefit during food production
breaking down lactose for lactose intolerant individuals
Which of these occurs through symbiotic nitrogen fixation
all of the above
Synthetic compounds found in an organism but not normally produced or expected to be present in that organism are called _______.
xenobiotics or c. recalcitrant compounds
. MRSA has emerged as a serious infectious disease, with the first case of methicillin resistant S. aureus being detected in 1961. Why are medical professional so concerned when antibiotic exist that can kill MSRA
. MSRA could acquire additional antibiotic resistance genes form other bacteria to become a super bug
Bioremediation includes _______.
. the use of prokaryotes to clean up pollutants
Which statement is true
Viruses are ACELLULAR
The viral ______ play(s) a role in attaching a virion to the host cell
BOTH the capsid and the envelope
Viruses ______.
VARY in shape
The observation that the bacteria genus Chlamydia contains species that can only survive as intracellular parasites supports which viral origin hypothesis
PROGRESSIVE viral origin hypothesis
A scientist discovers a new virus with a linear, RNA genome surrounded by a helical capsid. The virus is most likely a member of which family based on structure classification
. Rabies virus
Which statement is NOT true of viral replication
A lysogenic cycle kills the host cell
Which statement is TRUE of viral replication
during attachment, the virus attaches to specific sites on the cell surface.
Which statement is true of reverse transcriptase
It transcribes RNA to make DNA
Oncogenic viruses cores can be-
either RNA or DNA
Which is true of DNA viruses
they use the host cell’s machinery to produce new copies of their genome.
A bacteriophage can infect__________
bacteria
People with the CCR5Δ32 mutation of a T-cell surface protein can be exposed to some strains of HIV-1 without becoming sick. What step of the virus life cycle is likely to be inhibited with this mutation?
attachment
AN apple grower notices that several of his apple trees with fungi growing on their trunks have developed necrotic ring spots, while other trees in the orchard that lack fungi appear healthy. Hats is the most likely conclusion the farmer can make about the virus infecting his apple trees
The apple trees were infected by horizontal transmission.
Which of the following is NOT used to treat active viral disease
antibiotics
Vaccines
stimulate an immune response
A patient presents at the clinic with an acute viral infection. Assays that analyze the viral lifecycle classify the virus into Group V with a segmented genome. Which virus is the most likely diagnosis for the patient
rabies virus
Which of the following is not associated with prions
DNA
Which statement is true of viroids
They are single-stranded RNA particles