MICROBIOLOGY

Which of the following is not true of Lipopolysaccharides?

• It has been called the exotoxins to gram-negative bacteria because it firmly bound to the cell surface and is released only when the cells are lysed.

• It has a lipid A which is attached to a polysaccharide made up of a core and a terminal series of repeat units.

• It is synthesized on the cytoplasmic membrane and transported to its final exterior position.

• It is noncovalently cross-bridged by divalent cations, which stabilizes the membrane and

What comprises the outer leaflet of the outer cell membrane of the gram-negative cell walls?

• Porins

• LamB

• Lipid A

• Lipopolysaccharide

All of the following describes the Cell wall of bacteria, except

• It has a high-tensile strength.

• It gives osmotic protection.

• Various layers are the sites of major antigenic determinants of the cell surface.

• It is selectively permeable.

The simultaneous transport between Hydrogen and sodium in opposite direction by a common carrier is transported via

• Uniporters

• Antiporters

• Symporters

• ABS Transport

The difference between prokaryotes from eukaryotes is the absence of this steroids in its cell membrane. What is this steroid?

• Cholesterol

• Isoprenoids

• Sterols

• Glucocorticoids

Where do prokaryotes package their DNA?

• Mesosomes

• Fimbriae

• Nucleoid

• Histones

What is the protein component of the microtubules?

• Tubulin

• Actin

• Myosin

• Microfilaments

What proteins that binds to the eukaryotic DNA macromolecules by ionic interactions?

• Microfilaments

• Histones

• Myosin

• Tubulin

Which of the following structure are found almost exclusively among microbes in aquatic habitats?

• Magnetosomes

• Volutin granules

• Chromatic Granules

• Gas vesicles

What is not true of tat pathway?

• It is found in BOTH gram-negative and gram-positive bacteria.

• It can move proteins across the cell membrane.

• It is distinct from the sec system in that it translocates already folded proteins.

• In gram-negative bacteria, the proteins it transports are then delivered to the Type III system.