Question

Melissa is studying a Gram-stained slide of curd bacteria. She sees many rod-shaped, violet-colored bacteria.

What type of bacteria are they?

Answer 1

When we color bacteria with a "Gram stain," we're trying to find out which two groups of bacteria it could be:
1. Gram Positive2. Gram Negative
Gram POSITIVE bacteria turn PURPLE, when we stain them. Gram NEGATIVE bacteria turn PINK when we stain them.

They are lactobacilli. Bacilli are rod-shaped; spirochaetes are spirals; cocci are spheres.