How torchlights can indicate the presence of oxygen in the cave? how does the torch function?

Since fire is a chemical reaction, and oxygen is needed for that reaction, having a fire in a cave is a sure sign of the presence of oxygen.

Characteristic expected of mineral from lava at earth's surface

phaneritic textures in which phaner means visible so phaneritic textures are standard of impertinent volcanic rocks. these rocks crystallized gradually under the surface of earth. when the magma cools deliberately then the ores have chance to develop and produce long crystals.

Centriole.centrioles are present in animal cells but are usually absent in plant cells.