microbiology inventory concept september

How would you interpret the following phylogenetic tree of life?

Animalia and Fungi are more closely related to each other than Thermotoga and Aquifex. (same branch vs different branch)

How do vaccines and antibiotics each function?

Antibiotics target specific bacterial structures while vaccines contain bacterial structures.

Some strains of Bacteria are susceptible to the antibiotic penicillin though Archaea are not. This is because

Archaea have structural differences that impact susceptibility to penicillin

A patient has a catheter in his urinary tract. The catheter becomes colonized with bacteria and a biofilm forms. What triggered biofilm formation?

As more bacteria colonize the catheter, they will communicate and form a biofilm.

A mouse raised in a germ free environment completely lacks any "normal microbiota" or bacterial community. Aside from stimulation of the immune system, how would this affect the mouse's ability to resist disease-causing organisms?

The mouse would be more susceptible to disease, as normal microbiota suppresses pathogens.

How could the loss of a carbohydrate biosynthesis gene affect a bacterium that normally causes tooth decay?

Without a capsule, the bacteria cannot adhere to the surface of the teeth and cause tooth decay.

The most appropriate microscope for visualizing a living bacterial cell that is non-pigmented and unstained is:

a phase contrast microscope because it can differentiate cell structures better.

Strains of Lactobacilli are used to make cheese because they ferment. If a bacterium uses fermentation as its only source of metabolism, it will grow:

at the same rate in either the absence or presence of oxygen.

For a gene that is only regulated by a repressor, a mutation that destroys the activity of the repressor would:

cause the gene to be expressed at a higher rate since the repressor is inactivated.

finding common metabolic pathways such as tricarboxylic acid (krebs cycle) in prokaryotic and eukaryotic organism is

evidence that these current pathways are derived from early prokaryotic processes

Scientists have identified an oxygen-free, dead zone where the Mississippi River enters the Gulf of Mexico. The increase in corn production in Midwestern states that border the Mississippi River has increased the size of this zone due to:

fertilizer run-off affecting growth of organisms

Examine the graph, shown above, depicting a bacterium's growth rate at different temperatures. If the bacterium is shifted from 30°C to 40°C, it will:

grow slower because of decreased enzymatic activity.

Your company wants to make large quantities of human growth hormone (hGH). You propose to clone the entire hGH gene from the chromosomes of a healthy human and place it into the DNA of E. coli. These E. coli will NOT begin synthesizing hGH because:

human genes contain DNA sequences that interrupt the protein code that cannot be removed by bacteria.

if bacterial cells are exposed to an antibiotic for the first time they will

lack resistance because their immune system must see antibiotic in order to develop resistance

A unique metabolic property of Bacteria that is not found in Eukarya is:

nitrogen fixation.

To induce protective immunity against a disease, a vaccine must always provide

structural similarity to portions of the microorganism.

Ocean-dwelling chemoheterotrophic bacteria that generate energy via aerobic respiration are dependent on the presence of photoautotrophs like cyanobacteria because:

the cyanobacteria produce oxygen by photosynthesis needed for respiration.

After a large oil spill in the ocean, research has shown:

the naturally-occurring organisms play the major role in the cleaning process.

The above graph shows the primary and secondary immune response to a specific pathogen. The difference between the two responses is the result of:

the production of memory cells during the primary exposure makes the response faster.

As most microbes reproduce asexually, "species" are defined by differences in their DNA sequences. When the genome of soil microbe A is analyzed, long stretches of genes from multiple species of other soil microbial species are discovered. This indicates that:

there is transfer of genes from other soil microbe species

Eukaryotes use membrane bound organelles for respiration and photosynthesis, while prokaryotes:

use the cytoplasmic membrane for respiration and photosynthesis.

The model organism Escherichia coli is growing in a nutrient rich environment. If glucose is depleted, what would be the first response of Escherichia coli to the change in the environment?

utilization of another carbon source.

In order to produce mature viral particles after entering a eukaryotic host cell, a negative (noncoding) strand RNA virus replicates its genome using a:

viral-encoded enzyme to synthesize RNA.