Micro Final Exam 3-4

The nitrogenase enzyme uses a great deal of energy to reduce atmospheric nitrogen (N2) to _______ so that it can be assimilated into biomolecules. [1] NH4 +(ammonium ion) [2] N2O (nitrous oxide) [3] NO2- (nitrite) [4] NO3- (nitrate) [5] atomic nitrogen (N)

1

When you consumed just the corned beef, what percentage of the original biomass energy from the grain consumed by the cow actually enter your biomass?

1%

Flammable gas, dubbed "marsh gas or swamp gas", has been detected bubbling out of Asian rice paddies. Which of the following microbial reactions might best account for this gas? [1] 6CO2 + 6H2O --> C6H12O6 + 6O2 [2] 6CO2 + 6H2O + 3H2S --> C6H12O6 + 3S [3] CO2 + 4H2 --> CH4 + 2H2O [4] C6H12O6 + 6O2 --> 6CO2 + 6H2O

3

From the previous question:Lenski frequently froze culture of Cit - E. coli at different time points (generation number) during the experiment.Which frozen generation number had the highest probability of mutating into a Cit + E. coli culture (i.e it was finally able to grow with citrate as its carbon source)?

30,000

You would correctly expect to find FoF1 ATP synthase molecules inserted into the membranes of.... a. obligate anaerobic bacteria b. all of those listed c. obligate aerobic bacteria d. green sulfur bacteria e. cyanobacteria

B

The excess of protons (H+) outside the bacterial membrane is the PMF (proton motive force or ∆ p ) that can be represented as a combination of the differnces in electrical potential as well as differences in _________ across the cell membrane.

Electron concentrations

Which enzyme catalyzes proton pumping only when it works in reverse?

F0 F1 ATP synthase

Syntrophy [aka metabolic symbiosis] in the termite gut consist of a ___________microbe and a __________microbe acting in that order so that celloluse can be catabolized.

Fermentative; methanogenic

A microbiologist develops a new medium for culturing aerobic bacteria in which pyruvate is substituted for glucose (as the carbon source). You would predict that, if this culture is well aerated (provided with oxygen), ______ would therefore occur less often in the presence of more pyruvate.

Glycolysis (EMP)

Substrate-level phosphorylation produces a net total of 2 ATP per molecule of glucose during...

Glycolysis (EMP)

PS1: You are most likely to see this reaction in...

Green sulfur bacteria

PS1: Match process [left column] with its correct description [right column].

H2S

Which of these is the most powerful electron donor? E' (mv) Hydrogen -420 NADPH -324 lactate -185 succinate +30 oxygen +840

Hydrogen

From previous question: In that dark hot hydrothermal vent the producer you cited is most likely to use super-hot ______ as its electron donor. 1. carbon dioxide CO2 2. water vapor H2 O 3. sodium chloride 4. NaCl ammonia NH3 5. hydrogen sulfide H2S

Hydrogen Sulfide

At the bottom of very deep lakes or sewers, methane (CH4) often forms because some microbes are able to use _____to donate electrons to ______ during the process of methanogenesis.

Hydrogen; Carbon dioxide

If electron transport system (ETS) is stops working due to lack of oxygen during respiration, what would be another way of regenerating NAD+ from NADH?

Lactate Fermentation

Harold Urey and Stanley Miller started their "origin of life" experiment with these special gases because they had been detected in the atmosphere of Jupiter.

Methane, hydrogen, ammonia

Richard Lenski's Long Term Evolutionary Experiment (LTEE) use 33,000 generations of Cit- E. coli to study the mutational patterns in evolution. List one major conclusion of this 15 year experiment:

Mutation patterns may be non-random due to potentiation

______________ represents a parasitic form of symbiosis.

Mycobacterium tuberculosis in a human lung

The _________ reaction often occurs within airtight leguminous plant root nodules. Within those nodules you would expect to find Rhizobium bacteria in a symbiotic relationship with the plant.

Nitrogenase

The following 3 questions concern the Theory of Endosymbiosis first proposed by Lynn Margulis. Endosymbiosis radically changed the course of evolution ~ 2 billion years ago.For modern (eukaryotic) cells, the presence all the following within mitochondria[with the exception of _________ ] strongly support this theory.

Nuclear membranes

The rate-limiting step for glycolysis occurs with the ___________ reaction.

PFK

Many halophiles are associated with the Great Salt Lake. Some have the pigment bacteriorhodopsin, a light-driven proton pump. Others have halorhodopsin, a light-driven chloride pump. In both cases, the light energy is converted directly into _____________.

PMF

The complex FoF1 ATP synthase molecule is a kind of "energy transducer", i.e. it can convert one form of energy to another. It performs this task by converting _____ energy to _______ energy and finally to _______ energy within ATP.

PMF, mechanical, chemical

The Pasteur Effect describes different metabolic reactions in yeast based upon the presence or absence of oxygen. This occurs because the enzyme _______ is allosterically regulated by products of respiration.

Phosphofructokinase (PFK)

PQ (plasmoquinone) , a mobile electron carrier, is __________ during the "Z Scheme"

Reduced and then Oxidized

Chloroplasts differ genetically from their reputed ancestral cells in these the current organelles seem to have undergone...

Reductive evolution

Accordingly the the RNA World Theory, early life on the Earth may have used RNA instead of proteins for catalytic activity. Therefore you would correctly predict that _________ today most closely reflect the activity of such ancient RNA.

Ribozymes

A cow's gastrointestinal system includes the _________, a 40 gallon chamber that includes more than 1015 mostly fermentative microbes.

Rumen

Electron transport must occur ...

Within the cell membrane

Within the pelagic water column, you are more likely to find producers thriving without light in the ________.

benthic zone

The energy to synthesize glucose in the Calvin Cycle is derived directly from...

both ATP & NADPH

An ecosystem heated by a hydrothermal vent in the benthic zone would most likely have a microbe that could perform _________ in order to produce glucose.

chemosynthesis

Genomic sequencing of chloroplasts in plants today reveal that these organelle bear the closest genetic homology to....

cyanobacteria

Genomic sequencing of chloroplasts today reveal that this organelle bears the closest genetic homology to....

cyanobacteria

The most significant events illustrated on a phylogenetic tree that ensured the development of multicellular eukaryotic life was most likely...

endosymbiotic formation of mitochondria & chloroplasts

The most common enzyme reaction, catalyzed by RuBisCO, .....

fixes carbon to a 5-carbon molecule in the Calvin cycle

Toxins released by the obligate anaerobe Clostridium perfringens cause extensive cell membrane damage and eventual ......

gas gangrene

As you know, the mitochondrial genome has been subject to reductive evolution. Therefore you would correctly predict that "housekeeping genes" associated with _______ are still found within mitochondrial DNA.

protein synthesis

Clostridium aceticum, a hydrogenotroph, is capable of fermenting carbon dioxide to acetic acid by the following reaction: 4H2 + 2CO2 → CH3 --COOH + H2O ∆Go ' = -107 kcal/mol You would correctly predict that this reaction....

will proceed spontaneously left-to-right

Determine whether the process in the left column is indictative or assimilation or dissimilation [right column]. 1. Methanogenesis 2. Calcin cycle 3. Glycolysis 4. Nitrogenase reaction 5. Fermentation

1. Assimilation 2. Assimilation 3. Dissimilation 4. Assimilation 5. Dissimilation

Indicate which pathogen [left column] is associated with what diseases or symptoms [right column]. 1. Mycobacterium leprae 2. Mycobacterium marinum 3. Heliobacter pylori 4. Clostridium perfringens 5. Thiomicrospira (archaea)

1. Causes analgesia (loss of pain) in hands and feet 2. Causes TB-like disease in fish, granulomas in humans 3. Stomach ulcers 4. Gas gangrene often resulting in amputation 5. Not a pathogen!

Match the enzyme [left column] with its common location [right column] 1. RuBisCO 2. Nitrogenase 3. PFK 4. Cytochrome oxidase complex

1. Cyanobacteria carboxysome 2. Heterocyt 3. Cytoplasm 4. Cell membrane

Choose whether the following are high energy or low energy compounds: 1. NADH 2. AMP 3. NADP 4. ATP 5. Ribulose 1,6 bisphosphate

1. High 2. Low 3. Low 4. High 5. High

Match the following phylogenetic terms with their most accurate description: 1. Node 2. Clade 3. Root 4. Branch 5. Taxon

1. Most recent common ancestor from which 2 related species diverge 2. Large group that includes both ancestral species and all its decedents 3. Earliest common ancestor of all members of phylogenic tree 4. Horizontal timeline 5. Any phylogenetic category of classification of an organism

Match the organism(s) in the left column with the type of symbiosis in the right column. (Use each answer once.) 1. Neisseria meningitis infecting your brain parasitism 2. Mycobacterium smegmatis on your skin commenalism 3. Paramecium bursaria enveloping live photosynthetic green algae synergy 4. Cellulytic bacteria and methanogens in termite gut syntrophy 5. lichens

1. Parasitism 2. Commenalism 3. Synergy 4. Syntrophy 5. Mutualism

Match process [left column] with its correct description [right column]. 1. Metabolism 2. Anabolism 3. Catabolism 4. Pseudoreductionism

1. Sum of ALL processes in an organism 2. Biosynthesis; build-up of molecules from small precursors 3. Breakdown of large biomolecules into smaller ones, yields energy 4. Utter nonsense

Both Bacteria and Archaea Domains have ____________ in common.

A circular chromosome

The TEAs [terminal election acceptors] at the bottom of a deep lake have __________ standard reduction potential (Eo') compared to those located near the surface.

A more negative

Anaerobic Photosystem I Anaerobic Photosysem II Oxygenic Z Pathway In light of these 3 photosynthetic pathways, what do they all produce?

ATP

The fatty synthetase reaction uses ______________ as a substrate to assemble fatty acids in cell membranes.

AcetylCoA

The most distinctive feature of the element carbon that makes it the "prime ingredient" within so many diverse biomolecules is its ________

Affinity for itself

Intermediates of glycolysis or the TCA (Krebs) cycle can be used by microbes in the biosynthesis of _________. a. amino acids b. all macromolecules listed c. nucleotides d. fatty acids

All macromolecules listed

The planet Tralfamodore has a reducing atmosphere with frequent thunderstorms. You would correctly predict that a biological molecules like _________are most likely to form in this pre-biological environment.

Amino acids

Stillwater's main waste treatment plant uses the ___________ reaction to oxidizing excess ammonium [NH4+] from waste water in order to regenerate nitrogen [N2].

Ammanox

Because phospholipids are ______________ and dropped into a (polar) water solution, they spontaneously can form a liposome that may mimic an early cell membrane.

Amphipathic

The great majority microbes within the organ cited above are best classified as __________.

Anaerobes

During __________________, the electron donor and acceptor are the same molecule.

Anaerobic Photosystem II

Some pink-colored halophiles (Domain Archaea) in Great Salt Lake use the pigment __________________ to capture light in order to generate their PMF (proton motive force).

Bacteriorhodopsin

The beautiful pink and purple hues within Great Salt Lake are created byhalophillic photopigments such as __________ that absorb green wavelengths of light.

Bacteriorhopdopsin

All of the following processes represent horizontal gene transfer (HGT) EXCEPT....

Binary fission

During respiration, which step(s) produce(s) NADH?

Both glycolysis & TCA (Krebs) cycle

Your lunch just consisted of Old World corned beef and cabbage. Therefore you acted at what trophic level(s)?

Both primary and secondary consumer

The PFK (phosphofructokinase) reaction in glycolysis can be represented as... Fructose-6-phosphate + Pi → fructose 1,6 diphosphate ∆Go' = + 60 kJ/mole This means that this reaction...

Cannot proceed from left to right

About 2.5 billion years ago a dramatic increase in the atmospheric concentration of ____________ was likely a key step in setting the stage for the evolution of respiring multicellular organisms.

Carbon dioxide

Carl Woese (U. of Illinois) revolutionized phylogeny by proposing the new taxon of...

Domain

From which of the following taxa are you least likely to contract a pathogenic disease?

Domain Archaea

From which of the following taxa are you most likely to found numerous extremophilic microbes?

Domain Archaea

The "lollipop head" of ATP synthase (sticking down) represents the _____ region of this complex protein.

F1

Archaea were the last of the 3 Domains to be discovered and classified. Although technically prokaryotes, Archaea have ___________ in common with Eukarya.

Histones

__________ within cyanobacteria are specialized structure that enable nitrogen fixation to occur by preventing any exposure to ___________.

Heterocysts; oxygen

Before the TCA (Krebs cycle) can begin, ___________ must first be converted to ________, generating CO2 at the same time.(This is called the "transition step".)

Pyruvate; Acetyl-CoA

Which biomolecule does not have nitrogen incorporated into it?

Starch

When the ancient primitive eukaryote first attempted (unsuccessfully) to devour a photosynthetic bacterium by endocytosis, the following morning that bacterium and the host cell were involved in a __________ symbiotic relationship.

Synergistic

All of the following pathways EXCEPT _______ will produce both pyruvate & ATP.

TCA (Krebs cycle)

The __________ produces abundant amounts of both NADH and CO2 .

TCA cycle (Krebs cycle)

Ribulose-5-phosphate & NADPH, both vital for biosynthesis, are readily made during...

The Pentose Phosphate Pathway (PPP)

Sulfolobus solfataricus is an acidothermophile (a double extremoplhile). Therefore you would correctly predict that abiochemical analysis of Sulfolobus solfataricus would conclude that it contained....

a very high %G-C in its genomic DNA

In the Energy (Trophic) Pyramid, decomposers may perform dissimilation at ______level

any

Unlike Bacteria, Archaea are resistant to the penicillin family of antibiotics. This occurs because (unlike Bacteria,) Archaea _________.

do not have true peptidoglycan

The archaeal hyperthermophilic Thiomicrospira has been isolated from the trophosome (gut) of the benthic red tube worm. You would correctly predicts that proteins within this microbe have ___________ compared to mesophilic microbes in our bodies.

fewer glycine residues

Thermus aquaticus is a thermophile found originally in hot springs inside Yellowstone National Park. The proteins of this microbe are quite useful in biotechnology. You would correctly predict that those genomes within Thermus aquaticus have a much higher-than-average number of ___________ in order to strengthen their double-stranded DNA.

hydrogen bonds between bases

Within the organ cited above, CO2 can be reduced to _______ by using hydrogens (H) donated by ___________.

methane ; NADH

Many cases of Parkinson's Disease have been associated with a deleterious mutation within the DNA of human ...

mitochondria

Within the pelagic water column, you are more likely to find photosynthesizers in the ________.

neuston

Helicobacter pylori, the pathogen responsible for stomach ulcers, releases the enzyme urease. This enzyme enhances the environment for the growth of Helicobacter pylori, by....

raising the pH of the stomach contents

In the absence of oxygen, pyruvate is _________to lactate, regenerating NAD+

reduced

According to standards establish by the National Center for Biotechnology Information (NCBI), > 97% homology between 2 different microbes' 16S ribosomal DNA sequences indicates that those 2 microbes belong to the same...

species

What is an example of evidence today that RNA once played a key role in carrying genetic information (3 billion yrs ago) in the RNA World Theory?

the COVID-19 genome

Woese established his new phylogenetic tree by sequencing.....

the gene 16S rRNA