The parenteral portal is the entrance into the body by an abnormal route. In microbiology this usually means through a cut or bruise in the skin. No mention is made of inhaling, eating, or sexual activity.
Correct Answer: Skin (parenteral)
Many pathogens use molecules called adhesins, which are glycolipids or lipoproteins located on the pathogen surface, as a means of adhering to tissue. Some pathogens use glycoproteins found on the surface of host cells. E. coli uses adhesins on its pili.
Correct Answer: Adhesin molecules on bacterial pili attaching to gastrointestinal cells
Boring, adhesion by adhesins and by fimbriae, and forming biofilms are all part of establishment.
Correct Answer: Releasing endotoxin that will cause clotting
The LD50 is defined as the number of organisms required to kill 50% of the hosts. It does not indicate anything about the infectious dose, or specific genes.
Correct Answer: Kill 50% of the hosts
The infectious dose 50% (ID50) is the number of organisms
required for 50% of the population to show signs of infection. The lower the ID50, the greater the virulence.
Correct Answer: Organism A could be considered more virulent than organism B
Only hemolysin damages red blood cell membranes. Leucocidin affects white blood cells and coagulase, collagenase and hyaluronidase work outside of cells.
Correct Answer: Hemolysin
Hyaluranidase catalyzes the destruction of extracellular matrix. Coagulase is involved in blood clotting and hemolysin in blood cell membrane destruction.
Correct Answer: Hyaluronidase
Salmonella produces a molecule called invasin that can change the structure of actin filaments. The change in these filaments in turn moves the bacterium into the cell. Once inside the cell, it can use the cell’s actin filaments to move from place to place.
Correct Answer: Change the structure of actin filaments in host cells
Exotoxin production is primarily the activity of Gram-positive organisms. Exotoxins are secreted from living cells.
Correct Answer: Gram-positive bacteria
Exotoxins include neurotoxins, cytotoxins, and enterotoxins. Lipopolysaccharide, lipid A, and disseminating clotting factor are all endotoxins.
Correct Answer: Neurotoxins, cytotoxins, and enterotoxins
There are seven types of botulinum toxin, and all of them inhibit the release of the neurotransmitter acetylcholine. This disrupts the neurological signaling of skeletal muscles and results in paralysis.
Correct Answer: Neurotoxin
C. tetani produces tetanus toxin which causes muscles, including those in the jaw, to contract.
Correct Answer: Produce a toxin that causes jaw muscles to remain contracted
Endotoxins are bacterial toxins that are part of the cell wall of Gram-negative bacteria. They are active only after a bacterium containing them has been killed. Once the bacterial cell is dead, the endotoxins leave the cell wall and enter the bloodstream of the infected host.
Correct Answer: They are toxins found on Gram-negative cell walls
Large amounts of endotoxin can cause more serious problems such as shock and disseminated intravascular clotting (DIC), a condition in which minor clotting occurs throughout the body.
Correct Answer: Endotoxins