Viruses
Nucleotide analogs are a class of drugs that are highly effective against many types of viruses. They work by halting the replication of viral genes. They are equally effective at stopping the spread of prion diseases.
True or False?
False
Early classification systems of the bacteria employed all of the following characteristics except
A) spore formation
B) the ability to photosynthesize.
C) colony or filament forming.
D) motility.
E) rRNA sequences.
E) rRNA sequences
If you were to replace the phosphate group of a phospholipid with a fatty acid chain, you would have __________.
Triglyceride
If a cell has the same internal concentration of dissolved molecules as its outside environment, the cell's condition is referred to as being
DOUBLE POINTS!!!!
Hypotonic
The unique double shells of diatoms are made of
DOUBLE POINTS!!!!
Silica
A doctor's office has run out of the latest flu vaccine, but many patients are asking for it. One of the nurses finds some vials from last year's batch in a refrigerator. Should they be used?
No, because each year the vaccine is made against different subtypes of the flu virus.
A microbiologist explains to one of her biology classes that her research focuses on the nucleoid region of the cholera bacteria. This means that she is studying a region within the bacterium that contains the
Nucleic Acids
Osmosis occurs as water crosses the lipid bilayer through specialized channels for water movement called_________.
DOUBLE POINTS!!!!
Aquaporins
Proteins are formed through _________ Bonds.
Peptide
Oomycetes are characterized by all of the following except they DOUBLE POINTS!!!!
A) contain two unequal flagella.
B) contain motile spores.
C) produce zoospores asexually.
D) are able to reproduce sexually.
E) are considered fungi.
E) are considered fungi
While they are simple relative to cells, viruses often have a very diverse collection of components. Name at least 2.
DOUBLE POINTS!!!!
single-stranded DNA
membrane components
glycoproteins
proteins with functional binding sites
Prokaryotic cell movement is attributed to ________.
Flagella
In bacteria and cells of fungi and plants, the high internal pressure generated by osmosis is counteracted by the mechanical strength of their
DOUBLE POINTS!!!!
Cell Walls
The evolutionary process that created chloroplasts and mitochondria is __________.
Symbiosis
A new protist species is discovered with these characteristics: contains phycoerythrin and phycocyanin, lacks flagella and centrioles, photosynthesizes, haplodiplontic, and lives in coral reefs. What group does it likely belong to?
A) Stramenopiles
B) Chlorophytes
C) Rhodophytes
D) Charophytes
E) Amoebozoa
Rhodophytes
Gardasil is marketed as a cervical cancer vaccine, but it is actually a human papilloma virus (HPV) vaccine. Why is this done?
HPV in the cervical epithelial cells may cause the cells to become cancerous.
DNA replication and gene expression machinery in archaea more closely resemble eukaryotic cells than the same processes in bacteria. However both bacteria and archaea are prokaryotic. What does this suggest?
Eukaryotes shared a more recent common ancestor with archaea than with bacteria.
The fluid nature of the membranes is attributed to a lateral movement of _________.
phospholipid molecules
Which are features of mitochondria that reflect their endosymbiotic origin?
Mitochondria genes are translated by ribosomes similar to bacterial ribosomes.
They have their own circular genome.
Transferring Euglena into a dark environment results in the loss of photosynthetic pigment. What conclusion does this support?
A) Euglenoids are closely related to plants.
B) Light triggers heterotrophy.
C) Euglenoids are neither plant-like or animal-like protists.
D) Euglenoids are obligate photoautotrophs.
Euglenoids are neither plant-like or animal-like protists.
Once a prophage is present in a bacterial genome, viral genes are reproduced every time the bacterium multiplies. Expression of viral genes, however, is inhibited by a repressor protein. Cell stress can induce the formation of proteases that degrade the repressor. What will result?
The virus will enter the lytic cycle.
Vibrio cholerae lives in water and gets toxin genes from a virus by phage conversion. The toxin kills the intestinal epithelial cells in the human host, resulting in massive diarrhea. Untreated cholera has about a 50% mortality rate. How do the bacteria benefit?
Diarrhea helps the bacteria to spread from person to person.
What initiates the sodium-potassium pump?
Three sodium ions bind to the cytoplasmic side of the protein.
A circular molecule of DNA devoid of any histone proteins describes the chromosome of ___________.
Bacteria or Archaea
Protists are classified into a single kingdom because of which of the following features?
They are eukaryotes, but not fungi, plants, or animals.