1) What is the purpose for using simple staining?

a. Determine the size of the bacterial cells

b. Determine the shape of the bacterial cells

c. Determine the arrangement of the bacterial cells

d. To observe bacterial cells that are not easily distorted after heat fixing

e. All of the above

2) Why do bacteria stain during simple staining?

a. The positive charge on the bacterial cell wall repels the crystal violet and prevents it from entering the bacterial cell.

b. The negative charge on the bacterial cell wall attracts the crystal violet and allows it to enter the bacterial cell.

c. The positive charge on the bacterial cell wall attracts the crystal violet and allows it to enter the bacterial cell.

d. The negative charge on the bacterial cell wall repels the crystal violet and prevents it from entering the bacterial cell

3) The two main purposes for heat fixing are to kill and adhere the bacteria to the slide.

True

False

4) Preparation of a heat fixed smear in simple staining involves

a. spreading a mixture of bacteria and crystal violet across the slide surface from one end to the other.

b. drying the bacteria on the slide and then quickly heating the slide before staining with crystal violet.

c. heating the bacteria in crystal violet before placing the mixture onto a slide.

d. rapidly heating a slide before applying a mixture of bacteria and crystal violet.

5) It is important to gently evaporate off the water that the bacteria are in before heat fixing because

a. the bacteria will begin to grow in the water

b. the water will crystallized after heating

c. the bacteria may lyse in the water when heated

d.it is not necessary to evaporate the water off of the slide

6) If too little heat is applied during heat fixing

a. the bacteria will be lost from the slide

b. the bacteria will absorb too much crystal violet

c. the bacteria will become distorted

d. the bacteria will absorb too little crystal violet

7) If too much heat is applied during heat fixing

a. the bacteria will be lost from the slide

b. the bacteria will absorb too much crystal violet

c. the bacteria will become distorted

d. the bacteria will absorb too little crystal violet

8) A small number of bacterial species have a preponderance of positive charges on the outside of their cells. How would the bacteria if they were stained with crystal violet?

a. Purple bacteria on a clear background

b. Transparent bacteria on purple background

c. Purple bacteria on a purple background

d. Transparent bacteria on a clear background