What would be the consequence of an ecosystem that had no nitrogen-fixing bacteria?
a. nitrogen from decomposing animals would never be returned to the soil.
b. decomposers would not be able to break down the nitrogen present in plants they feed on.
c. plants would have to rely on biologically available nitrogen present in the soil.
d. consumers would not survive since they would have no way to obtain the nitrogen they need.

they deliver oxygen to the blood

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.

1)

i))the process of preparing food by green plants in the presence of sunlight is called photosynthesis.

ii) leaf is the site for photosynthesis.

iii) it takes place as,

6h2o+6co2=c6h12o6+602