Obtaining Carbon Compounds in Ecosystems

what must happen to all chemical energy stuck in nutrients

must be recycled

how is the recycling achieved

achieved by fungi, bacteria, insects and earthworms

what are decomposers supplied with

energy from carbon compounds in dead organic matter

examples of dead organic matter

faeces, shed of exoskelettons of an insect or reptile, dead plant material exoskeletons

what is a special group of deocomposers

saprotrophs

what organisms are the main representatives of this

fungi and mushroom

what do saprotrophs do

secrete digestive enzymes into dead organic matter and digest it externally

how do they digest it externally

by absorbing the products of digestion (sugars, amino acids)

what else do saprotrophs break down

complex insoluble carbon compounds into soluble ones

what are the consumers and producers in the food chain

heterotrophs = consumers, autotrophs = producers

what does an autotroph do

produce its own organic molecules from simple inorganic molecules

what are the two type of autotrophs

• photoautotrophs

• chemoautotrophs

what are photoautotrophs

make organic compounds using light energy to fix CO₂ into organic molecules

what are chemoautotrophs

make organic compounds using energy from the oxidation of chemicals

what compounds can chemoautotrophs oxidise and then synthesise in the form of carbon compounds

sulfur, hydrogen, iron sulfides, hydrogen or ammonia

where is iron sulfide found as a source for chemoautotrophs

sedimentary rocks formed in low oxygen environments

what happens during mining or eriosion

rocks are exposed to air

what does this result in

iron oxidising bacteria use Fe²⁺ ions and oxidises them further into Fe³⁺

what do the electrons in this reaction do

drive energy production (ATP) in the cell membrane

what do heterotrophs do

gain their carbon compounds by ingesting tissues of other organisms

what determiens the classification of the heterotrophs

the digestion

what is assimilation

the process where digested nutrients are made part of the cell by building up complex macromolecules