Exam 3: Bacteria and Archaea

The term used to describe bacteria that have a spherical shape is

Proteins that are embedded within the cytoplasmic membrane and not easily extracted are called __________ proteins.

In many spirochetes, multiple flagella combine to form a bundle known as a(n) ____________ fibril, which winds around the cell and confers motility on the cell.

All of the following statements about the periplasmic space are true except:

The layers of peptidoglycan of the bacterial cell wall can be cross-linked by peptide intrabridges or by direct cross-linking.

Enzymes that are secreted out of the cell to aid in the acquisition and digestion of environmental nutrients are called __________.

Gram-positive bacteria have a structurally and chemically more complex cell wall than gram-negative bacteria.

Gram-positive bacteria have a thinner layer of peptidoglycan than gram-negative bacteria.

_______ is a peptidoglycan-like molecule found in the cell walls of some archaea.

Flexible bacteria with a helical shape are called

Proteins that are loosely associated with the cytoplasmic membrane are called __________ proteins.

Export of flagellin subunits is mediated by

A __________ layer consists of diffuse unorganized polysaccharide material that lies outside the cell wall and is easily removed.

The hydrocarbons found in the membranes of archaea are identical to those found in bacteria.

A(n) __________ layer is a layer of protein or glycoprotein that exhibits a pattern resembling floor tiles.

Twitching or gliding motility involves

The concept of a prokaryote was first fully outlined in 1962 by

The most widely accepted current model for membrane structures is called the __________ model.

Rigid bacteria with a helical cell shape are called

Molecules or regions of molecules that readily interact with water are said to be __________, whereas molecules or regions of molecules that are insoluble in water or do not readily interact with water are said to be __________.