Most Missed Question Exam 1

Question 1

In the early 1900’s, his work led to the discovery of antibiotics

Answer 1

Alexander Flemming

Question 2

In the late 1600’s, he build his own microscopes and was the first person to observe bacteria, which
he called “wee animalcules”

Answer 2

Antonie van Leeuwenhoek

Question 3

. In the late 1800’s, he developed a series of postulates that verified Pasteur’s germ theory of disease
and established a link between a microbe and the disease it caused.

Answer 3

Robert Koch

Question 4

T/F Of the cell wall, outer membrane, and cytoplasmic membrane: the cytoplasmic
membrane is the least permeable to solutes, while the cell wall is most permeable.

Answer 4

True

Question 5

T/F There are many types of viruses, but they are only known to infect humans and other
animal cells.

Answer 5

False

Question 6

Along with proteins, which of the following is a major component of the cytoplasmic membrane?

Answer 6

Phospholipids

Question 7

Which of the following is true of bacterial endospores?

Answer 7

They are much more resistant to heat, desiccation, and radiation than vegetative cells.

Question 8

Soon after their discovery, one of the groups of microbes that you have learned about was initially
referred to as being “filterable”. The term “filterable” was used because these microbes could pass
through a filter with a pore size of 0.2 micrometers (200 nanometers), suggesting that these microbes
were smaller than 0.2 micrometers. Based on what you have learned about the typical sizes of various
types of microbes, which of the following do you think this term was most likely applied to?

Answer 8

Viruses

Question 9

Consider the following hypothetical conditions: A population of 10,000 bacteria has a doubling time
of 2 hours, under a given set of growth conditions. The culture is allowed to grow for 4 hours in
exponential phase. Which of the following best predicts the population size at the end of the 4 hours
incubation? Assume there is no lag phase. You can use the following equation: Nt = (Ni) x 2n
, and the
following values: 20 = 1; 21 = 2; 22 = 4; 23 = 8; 24 = 16; 25 = 32.

Answer 9

B) 40,000

Question 10

Which of the following is true of bacterial flagellar motility?

Answer 10

It can facilitate chemotaxis by changing the relative proportion of “running” (forward motion) and
“tumbling” (reorientation).

Question 11

Which of the following is a major component of bacterial cell walls?

Answer 11

Peptidoglycan

Question 12

Bacterial endospores have which of the following characteristics?

Answer 12

Are formed under unfavorable growth conditions (e.g. substrate limitation) and germinate under
favorable conditions

Question 13

What occurs during the lysogenic state of a temperate bacteriophage? Chapter 3

Answer 13

The phage DNA integrates into the host cell genome and is replicated along with the host DNA.

Question 14

Which of the following is the most abundant type of macromolecule (as % of dry weight) in a typical
bacterial cell?

Answer 14

Protein

Question 15

One method for enumerating viruses is to incubate the virus on a plate (a soft agar overlay) in the
presence of ______ and count the number of resulting plaques.

Answer 15

host cells and necessary components for host cell growth

Question 16

Which of the following describes an organism able to use organic carbon as a C source and chemical
energy to make ATP?

Answer 16

Chemoheterotroph Chapter 4

Question 17

A given microbe is able to oxidize glucose by respiration with oxygen as a terminal electron acceptor,
if it is present; in the absence of oxygen, this microbe can instead us nitrate (if present) as an alternative
electron acceptor or may use fermentation. Based on this, this microbe can be described as a(n) _____.

Answer 17

facultative anaerobe

Question 18

Fermentation is different from respiration in several key aspects, including that

Answer 18

Fermentation utilizes organic electron acceptors, while respiration uses inorganic acceptors

Question 19

differences between gram positive and gram -?

Answer 19

Periplasmic space: present in gram - absent in positive

Question 20

Outer membrane

Answer 20

present in gram - absent in positive

Question 21

preventing cell lysis under hypotonic conditions and

for maintaining cell shape?

Answer 21

cell wall duh

Question 22

Structure ______ would be most responsible for the _______ color of this cell resulting from
application of the Gram stain procedure.

Answer 22

gram cell wall, purple

Question 23

This bacterium is capable of respiration and has an electron transport chain, including cytochromes,
quinones, and an ATP synthase, but these structures are not shown on the diagram. If they were shown,
in which structure or region would these be found?

Answer 23

below cytoplasmic membrane-both cells have cytoplasmic membrane