Question

Which scientist / experiment provided the most compelling evidence to disproved Aristotle's theory of Spontaneous generation?

1) Pasteur's swan neck experiment

2) Lazzaro's mutton broth experiment

3) Redi's flask and meat experiment

4) Pasteur's flask and meat experiment

Antibiotic resistance genes may be transferred from one bacteria to another by conjugation via....

1) the sex pilus

2) porins

3) chemotaxis

4) gas vacuoles

Which of the following is not true of Gram-positive bacteria?

1) Posess an outer membrane composed of lipopolysaccharides that acts as a permeability barrier

2) Have a thick peptidoglycan layer that provides stability from osmotic pressure

3) Some species have the ability to form highly resistant spores under stress

4) Teichoic acid is attached to their peptidoglycan layer and functions to provide structural support

Which of the following is not a function of microbes?

1) All are functions of microbes

2) Aid in food digestion

3) Supply important vitamins to some hosts

4) Stimulate host immune system development

5) Cycling of critical elements within the biosphere

All of the following are true about outer membrane porins EXCEPT:

1. They are located in the plasma membrane of gram-negative bacteria
2. They are often trimers
3. Some antibiotics access their targets after diffusing through the porins
4. They are hour-glass shaped and this constricts the size of molecules that can pass through

Which of the following will NOT be found in the plasma membrane of a prokaryote?

1. Cholesterol
2. Hopanoids
3. Phospholipids
4. Integral membrane proteins
5. Transmembrane proteins

The bacterial cell wall (peptidoglycan) is composed of

1. crosslinked polymers of NAM and NAG
2. phospholipids
3. lipoproteins
4. structural L-amino acid containing proteins

A Gram-negative bacterium is enclosed by..

1. 2 membranes, thin peptidoglycan layer
2. 1 membrane, thin peptidoglycan layer
3. 1 membrane, thick peptidoglycan layer
4. 2 membranes, thick peptidoglycan layer

Bacterial flagella propel the cell by using....

1. a rotating motion

1. a whipping-like motion

1. two flagella that move in opposite directions, like a flutter kick

1. a beating motion

Fimbriae…

1. attach bacteria to various surfaces
2. allow bacteria to swim move through fluids
3. protect the cell from bursting
4. repel antibiotics

The bacterial nucleoid is comprised of…

1. DNA, RNA & protein
2. DNA only
3. DNA & protein only
4. DNA + histones

Plasmids are important because…

1. all are correct
2. they are inherited from one generation to the next
3. they may carry genes that give their host a fitness advantage
4. they can render bacteria drug-resistant

Which is true?   

1. Endospore formation is a developmental process that certain bacteria undertake during stressful growth conditions
2. Endospores allow a cell to attach to solid surfaces
3. A cell buds off one endospore and then the cell continues to grow
4. Endospores can divide in two to create 2 new cells

Answer 1

QUESTION 1

The correct answer is 1

In this case, remember that Aristoteles was the founder of the abiogenesis theory where it is established that life was originated from non living and inorganic material. However, Pasteur in the middle of 19th century, made an experiments which showed that bacteria wont be able to grow in an sterile closed flask. But if the broke the flask, the bacteria will grow. This experiment was named the swan neck experiment.

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