Microbiology Ch 4 Hwrk Quiz

The bacterial flagellum moves

by rotation that is powered by the proton motive force

Excess nutrients that the cell may store for later may be found within

cytoplasmic granules

Which of the following has historically been the first division in a system of bacterial taxonomy?

Gram-positive vs gram-negative cells

A taxonomical outline of bacterial species based on shared evolutionary histories would be described as

Phylogenic system

The best understood bacterial cytoskeletons are composed primarily of

actin

The two groups of obligate intracellular bacteria are the ______, usually spread by contact, and the _____, usually transmitted by the bites of arthropods.

Chlamydias; ricketssias

Which of the following explains why archaeons are extremophiles?

They are ancient, primitive organisms that adapt well to extreme conditions because they have retained characteristics of the cells that first evolved when earth's conditions were far more extreme

Other than maintaining the shape of the cell, what is the primary function of the cell wall, and which component contributes most to this function?

maintaining strength; peptidoglycan

Bacterial species are defined in a fundamentally different way than the mammalian species are. This is because

mammals reproduce sexually while bacteria reproduce asexually

Of the photosynthetic bacteria, cyanobacteria produce _____ as a product of photosynthesis but the green and purple sulfur bacteria do not produce this substance

oxygen

The molecule primarily responsible for the strength and stability of the bacterial cell wall is

peptidoglycan

The cell membrane is composed of

proteins dispersed throughout a phospholipid bilayer

Choose the answer that best completes this statement's blanks in the correct order. When all the flagella on a cell rotate in a counterclockwise fashion, the cell is propelled forward in a movement known as a _____, but when the flagella reverse direction, the cell stops and changes course in an action known as a _____.

run; tumble

The primary function of the cell membrane is

to regulate the transport of molecules in and out of the cell

The ____ level of bacterial organisms refers to a group of organisms that all share the same traits while the subspecies level refers to the variation or differences of individual cells within that group.

species

Ribosomes function primarily to

synthesize proteins