what is land plants functions?

Answer 1

What is their function? You are anthropomorphising evolution, meaning, you are assuming that organisms have evolved for a "function". Organisms evolve in order to pass on their offspring and to expand the species - that is all organisms' "function".

If you're asking what plants do in life... well.. that's something completely different and would entail plants being...

a) the creators of a "breathable" atmosphere for animals. If land plants had not invaded land first and had created the first "poison" (i.e. atmospheric oxygen), aerobic organisms could not have evolved (i.e. us!).

b) provide homes for creatures in and of themselves, and...

c) provide homes for creatures by growing in large forests, thereby founding the basis for the ecosphere, ecosystems, and communities...

d) shade is very important in many ecosystems such as savannahs, where large mammals could not survive without the shade provided from trees...

e) Leaf litter is an EXTREMELY large benefit for macro- and micro-invertebrates who consume and live within this dead organic matter.

f) provide stable land surface - many islands (for example mangrove islands) consist completely of plants! Other plants provide stability in ecosystems with high erosion rates.

g) provide humans and other animals with resources such as wood, twigs, fruit, tubers, etc.

Answer 2

In regard to what?

-- make food through photosynthesis (starting the food chains)
-- produce oxygen
-- remove carbon dioxide from the air
-- participate in the water cycle as well as the carbon, nitrogen, phosphorus, and other cycles
-- prevent erosion
-- make soil
-- provide shelter and shade

Answer 3

To provide oxygen

Answer 4

to turn carbon monoxide into oxygen through photosynthesis