Question

time remaining
catagorize the bacteria characteristics based on if they correspond to gram positive or gram negative bacteria.
gram positive\tgram negative
no answers chosen\tno answers chosen
possible answers
gram - stained cell is reddish - pink in color\tgram - stained cell is purple in color
no outer membrane or porins present\tcell wall has multiple layers (bilayer) with porins
multiple choice 1 point
why must we allow the metal loop to cool before retrieving bacterial colonies?
○ it can cause the bacteria to travel into the air
○ it can cause the bacteria to reproduce at an alarming rate
○ you dont need to let the loop cool - all bacteria thrive in excessive heat
○ excessive heat can kill organisms, and then we could see no growth

Explanation:

Part 1: Categorizing Bacteria Characteristics (Gram Positive vs Gram Negative)

• Gram - stained cell is purple in color: Gram - positive bacteria retain the crystal violet stain during the Gram - staining process, resulting in a purple color. So this characteristic belongs to Gram Positive.
• No outer membrane or porins present: Gram - positive bacteria have a thick peptidoglycan layer in their cell wall and lack an outer membrane (which contains porins in Gram - negative bacteria). So this is a Gram - positive characteristic.
• Gram - stained cell is reddish - pink in color: Gram - negative bacteria do not retain the crystal violet stain and take up the counter - stain (safranin), resulting in a reddish - pink color. So this is a Gram - negative characteristic.
• Cell wall has multiple layers (bilayer) with porins: Gram - negative bacteria have a cell wall structure with an outer membrane (a bilayer) that contains porins. So this is a Gram - negative characteristic.

Categorization:

• Gram Positive:
• Gram - stained cell is purple in color
• No outer membrane or porins present
• Gram Negative:
• Gram - stained cell is reddish - pink in color
• Cell wall has multiple layers (bilayer) with porins

Part 2: Multiple - Choice Question (Why cool the metal loop?)

• Option 1: A hot loop is not likely to cause bacteria to travel into the air. This is not the main reason for cooling the loop.
• Option 2: A hot loop does not cause bacteria to reproduce at an alarming rate. Reproduction rate is related to factors like nutrient availability, temperature range for growth (not extreme heat), etc.
• Option 3: Most bacteria do not thrive in excessive heat. In fact, excessive heat can kill them. So this option is incorrect.
• Option 4: A hot metal loop has a high temperature. Excessive heat can denature bacterial proteins and kill the organisms. If the bacteria are killed, there will be no growth when we try to culture them. This is the correct reason for cooling the loop.

Answer:

The correct option is: Excessive heat can kill organisms, and then we could see no growth