Question

In bacteria, the oxidative enzymes are found within
(a)Mesosome
(b)Cell wall
(c)Plasma membrane
(d)Flagella

Answer 1

Hint: Bacteria is a prokaryotic organism thus it does not have membrane-bound organelles. But for the functioning of respiration enzymes requires the presence of a membrane to be able to create a potential gradient.

Complete answer:
Mesosomes are extensions of the plasma membrane into the cell i.e. folded invaginations of the plasma membrane. These extensions can be in the form of vesicles, tubules, and lamella. Their functions include the formation of the cell wall, DNA replication, and distribution to daughter cells, etc. They help respiration by providing the oxidative enzymes a membrane to form a gradient. It also helps in secretion by increasing the surface area of the plasma membrane.

Additional Information:
Cell wall: Cell wall of the bacteria determines the shape of the cell. It also provides strong structural support to prevent bacteria from bursting or collapsing.
Plasma membrane: Plasma membrane is made up of a bilayer of phospholipids which allows substances to move materials selectively in and out of the cell.
Flagella: It is a filamentous extension from the cell wall and is responsible for providing motility to the bacteria.
So, the correct option is ‘Mesosome’.

Note: -In cyanobacteria, there are also membranous extensions that contain pigments and are known as chromatophores. This is needed for photosynthesis.
-Along with bacteria, there are also pili and fimbriae present on the surface of bacteria but they are not used for motility.
-Pili are made up of pilin protein which is responsible for sexual reproduction (i.e.conjugation) in bacteria.
-Fimbriae are small bristle-like structures that help attach them to rocks.