All life on Earth derives its energy directly or indirectly from the sun,except:

Pigments phycocyanin and phycoerythrin are found in

Which of the following may occur in arctic and alpine meadows?

Transfer of $DNA$ from one bacterium to another by contact is known as:

Consider the following four statements $(A-D)$ and select the option which includes all the correct ones only.
$(A)$ Archaebacteria differ from other bacteria in having a different cell wall structure.
$(B)$ Bacteria as a group show the most extensive metabolic diversity.
$(C)$ All Eubacteria have chlorophyll ' $a$' pigment similar to green plants.
$(D)$ Mycoplasma can survive without oxygen.

Where are bacteria $NOT$ found?