Similar to eukaryotes, bacterial cells are in accordance with the central dogma of molecular biology. The flow of genetic information involves replication, transcription, and translation. Bacterial cells have to replicate their genetic material (replication), undergo transcription to convert DNA to mRNA, and go through translation to produce proteins from the mRNA.

Bacterial cells do not undergo mitosis or meiosis. Cell division can occur through other modes, such as binary fission. Since bacteria lack nuclei and other complex structures, their processes for cellular division are much more abbreviated and do not follow the same steps as eukaryotic mitosis.

First, remember that all bacterial cell walls contain peptidoglycan. The difference between gram-positive and gram-negative bacterial cell walls rises from the composition of peptidoglycan. Gram-negative bacteria appear pink when observed through a microscope, not purple. Also, gram-negative bacteria have thinner cell walls than their counterparts.

Gram-positive bacteria have half as many cell membranes as gram-negative bacteria. This is true because gram-negative bacteria contain an extra cell membrane outside their cell wall. Gram-negative bacteria have two cell membranes, whereas gram-positive bacteria only have one.

If you place a cell in a hypotonic solution it means that the solution contains less solute (and more water) than the cell’s cytosol. Recall that osmosis causes water to go from a region of high water content (few solutes) to a region of low water content (more solutes).

In this case, the water will go from the solution to the inside of the cell, causing the cell to swell.

The name staphylococcus aureus contains the term "coccus," which indicates that the bacteria is round-shaped.

Rod shaped bacteria are classified as bacilli and helical bacteria are classified as spirilla.

Formation of a bridge between two cells occurs during conjugation. The bridge is called a sex pilus, which is used to carry genetic material from one bacterial cell to the other.

Transduction is another mode of reproduction, but involves transmission of genetic material through a vector. Vectors are generally host cells or virions that carry parts of the bacterial genome known as plasmids.

The third type of bacterial reproduction is called transformation. In transformation a bacterial cell engulfs and incorporates genetic material from its surroundings.

Translation is not a type of bacterial reproduction; it is the process by which proteins are made from mRNA.

Only gram-negative bacteria have an outer membrane. This outer membrane contains lipopolysaccharides. Gram-positive bacteria have only one membrane.

Teichoic acids are present only in gram-positive bacteria. They contribute to the thickness of the peptidoglycan layer.

Both types of bacteria have peptidoglycan. Gram-positive bacteria have a thick layer, due to the presence of teichoic acids. This allows them to retain the gram stain and appear purple. Gram-negative bacteria have a thin peptidoglycan layer, causing them to appear pink under gram staining.

Recall that pink stained cells are gram-negative, whereas purple stained cells are gram-positive. Based on color, we can conclude that cell A is gram-negative (pink) and cell B is gram-positive (purple). One of the characteristics of gram-positive cells is that they have a thick cell wall. The thick peptidoglycan cell wall stops the gram stain from leaking out, resulting in a darker color.

Since cell B is purple, we can conclude that it is gram-positive and has a thick cell wall.

The genito-urinary, respiratory, and digestive systems, as well as skin and mucous membranes, are natural physical barriers against infection.

Opportunistic microorganisms are normal fauna that are usually harmless; however, given the opportunity of a breach of any of our natural barriers, these organisms can invade vulnerable systems and cause infection, thus becoming pathogenic.

A pathogen that is an acidophile prefers highly acidic environments and therefore could survive the stomach's 2.0 pH - a lethal barrier to most organisms. The effectiveness of other natural barriers, however, would not be different because the organism is an acidophile.

All of these answers are true differences between prokaryotes and eukaryotes. Prokaryotes' DNA is double-stranded, but circular instead of linear, as in eukaryotes. This facilitates the expedient replication of multiple genes.  Eukaryotes have membrane-bound organelles, but prokaryotes do not. The more complex a cell is, the greater number of reactions and processes that need to be separated. Eukaryotes also have multiple replication origins most likely due to the length and distribution of their genes. Eukaryotes also do not have operons (present in prokaryotes) that are analogous to "gene packets," which are transcribed simultaneously. Since prokaryotic DNA is circular they have no "ends". Thus there are no need for telomeres which cover the ends of eukaryotic chromosomes. This loss of important genetic information at the end of transcription due to the antiparallel nature of DNA.

Bacteria are a type of prokaryote, which do not have any membrane-bound organelles, but do have circular, doubled-stranded DNA, ribosomes, and an outer membrane made of proteins and lipids. Since glycolysis does not require any organelles, it occurs in they cytoplasm of both prokaryotes and eukaryotes.