Question

1. Is oxygen necessary for the survival and growth of all microorganisms? Justify your answer.
Ans.
2. Name the three types of bacteria on the basis of their shape and draw their picture.
Ans.

Answer 1

Answer:

No.

Oxygen is just needed for aerobic respiration. Respiration is the most efficient way to turn glucose into energy, and oxygen is generally a very toxic compound… so it’s easy to see why most organisms that are exposed to oxygen are those who use it for their metabolism.

But there are many who don’t. There are alternatives to respiration, like fermentation. They are much less efficient, but still produce energy.

Most organisms capable of respiration are also capable of fermentation (even us!), but those who have evolved to rely on the superior energy output of respiration will die if all they have available is fermentation.

Yeast, for example, can do both, and that’s why wine bottles have to be kept closed during fermentation: if oxygen got inside, yeast would stop fermenting the wine and start oxydizing it instead! And that’s how you get vinegar.

And then… there are bacteria who are able to use other elements instead of oxygen for respiration. Like sulphur. Sulphur-”breathing” bacteria live in places where sulphur is abundant and oxygen is scarce, like deep sea volcanic vents, volcanic hot springs and such.

2.Bacteria are classified into five groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes).

Answer 2

1. One of the most-prominent differences between bacteria is their requirement for, and response to, atmospheric oxygen (O2).

Whereas essentially all eukaryotic organisms require oxygen to thrive, many species of bacteria can grow under anaerobic conditions.

2. Bacteria are classified into :

• spherical (cocci)
• rod (bacilli)
• spiral (spirilla)

I hope that the answer helps you mate ♡ ^_^