1If you examined pond water did you notice any bacteria swim

1.If you examined pond water, did you notice any bacteria swimmming in \"runs and tumbles\"? Did you notice any swimming in more-or- less in straight lines? If yes, describe the cell morphology.

2. Motility because of flagell is the most common form of bacterial locomtoion, but some bacteria glide. If you examined pond water, did you notice any gliding cyanobacteria? if yes, descirbe the morphology.

Solution

1.When bacteria undergoes random walks , it is called run and tubke method. Many many bacteria can be seen in the pond with Run and tumble methods

this method is used by only those bacteria which have flagella

When the flagella rotate clockwise it cause a Tumble but when they rotate counterclockwise it causes swimming motion

Example of this bacteria is E e coli bacteria which uses the run and tumble method to randomly walk in the pond.

The movement of these bacteria is due to chemical gradient that is caused due to the concentration of food

If The bacteria realises that there is the concentration gradient of a food in one particular direction it gets attracted towards it and continues to walk in straight line.

So these movements are the result of simply choosing between two methods of random movement that is tumbling and straight swimming, which is decided by the no. , postioning and structure of helical flagella and the concentration gradient