Essay Questions

EssayQuestions

EssayQuestions

Q1.

Theprocess of oxidative phosphorylation takes place in the mitochondria.Electrons are moved from FADH2or NADH to O2toform ATP. It involves proton-motive force generation during electrontransport. On the other hand, electron transport chain (ETC) is theseries of organic molecules and proteins in the inner mitochondriamembrane. Electrons moves through the members of the transport chainin a series of redox reactions (Murray,Rosenthal, and Pfaller, 2015).As a result, they release energy, which is captured as protongradient to make ATP through chemiosmosis process. The high energylevels of NADH electrons make it a good electrons donor in a redoxreaction. Therefore, it can directly transfer electrons to complex I.Contrary, the low energy levels of FADH2makes it a poor electron donor hence, it cannot move them to complexI.

Q2.

Glycolysisis the first stages of bacterial respiration that happens in a clearcytoplasm portion called cytosol. It involves splitting of glucosemolecule into pyruvic acid, a two- 3carbon molecule. Next is theKrebs cycle where the Acetyl-Coenzyme A (CoA) breaks down intoprotons and carbon dioxide. It then releases energy in the form ofelectrons, which are used by NAD+ to form NADH. The last stagehappens in the interior membrane of mitochondria. It involves thetransfer of NADH from one protein to another.

Respirationdoes not require oxygen, it produces water molecules, glycolysisoccurs in the cytoplasm, and it has a net gain of 32 ATPs.Conversely, fermentation requires oxygen, it does not produce watermolecules, all reactions take place in the cytoplasm, and it has anet gain 2 ATPs.

Q3.

Carbon-constituent of cellular material

Oxygen-constituent of cell water and material

Nitrogen-constituent of nucleic acids, amino acids, and coenzymes

Hydrogen-constituent of cell water and organic compound

Phosphorous– constituent of phospholipids,nucleic acids nucleotides, and teichoic&nbspacids

Definedmedium is a nutrient material with a known exact chemical compositionwhile the complex medium is a nutrient material with unknown exactchemical composition.

Q4.

Functionalmedia types are used in cell culture to facilitate microorganisms’growth. They include differential, selective, and enriched media.

Transportmedia is used prevent overgrowth of contaminated commensals andorganisms. Examples include alkaline peptone water and Cary-Blairmedium.

Selectivemedia is used to encourage and suppress the growth of desiredmicrobes and unwanted bacteria respectively. For example, brilliantgreen agar, campylobacter agar, and EMB agar.

Differentialmedia is used to differentiate colonies of the desired organism. Forexample, blood agar, CLED agar, XLD agar, and MacConkey’s agar.

Q5.

  1. Obligate aerobes are bacteria that grow in sufficient oxygen. Examples include mycobacterium tuberculosis and pseudomonas aeruginosa.

  2. Obligate anaerobes are bacteria that that grow without oxygen. Examples include Clostridium botulinum and Listeria.

  3. Facultative aerobes are bacteria that grow in either the presence or absence of oxygen. Examples include salmonella, Bacillus cereus, Staphylococcus aureus, and Shigella.

  4. Microaerophiles are bacteria that grow under increased carbon dioxide and reduced oxygen. Examples include Helicobacter pylori and Campylobacter jejuni.

Q6.

  1. Cell walls- protect the cell and give it a shape.

  2. Cell membrane- controls movement into and out of the cell.

  3. Outer membrane- shield the cell wall from antibiotics.

  4. Chromosome- carries genetic information.

  5. Cytoplasm- contains organic compounds, ribosomes, and DNA that are vital in carrying out a life process.

  6. Plasmid- consist genes that are obtained through recombination of genetic.

  7. Flagellum- moves the cell.

  8. Pilus- assists the cell to attach itself to other surfaces.

  9. Endospore- protects the cell from ruthless environmental conditions.

Thethree main steps of DNA replication are an initiation, elongation,and termination.

References

Murray,P. R., Rosenthal, K. S., &amp Pfaller, M. A. (2015).&nbspMedicalmicrobiology.Elsevier Health Sciences.