Science [2 Mark Questions]

Microorganisms like bacteria and fungi which helps in the breakdown of organic matter or biomass of dead plants and animals into simple inorganic raw materials and replenish the environment are termed as decomposers. Their existence is thus, essential in an ecosystem because
i. They help in the natural replenishment of soil.
ii. They help in keeping the environment clean as they reduce environmental pollution.

Pollination is the process of the transfer of pollen grains from the anther to the stigma of the flower. Which is achieved by the help of either biotic or abiotic factors. Such as insects (entomophily), wind (anemophily), water (hydrophily) etc. Agent are known as pollinators.
There are two modes of pollination in flowering plants:
i. Self-pollination
ii. Cross-pollination
Difference between self-pollination and cross-pollination are:

Self-pollination	Cross-pollination
In this, the pollen grain from the stamen of a flower is transferred to the stigma of the same flower which is Autogamy. Also, pollen grains from the stamen of one flower is transferred to the stigma of another flower of the same plant which is known as Geitonogamy.	In this, the pollen grain from the stamen of a flower is transferred to the stigma of a different flower. Which is known as Xenogamy. Which leads to development of new variety.