The Carbon Cycle & Decomposition Flashcards
Compound
2 marks
A substance formed by the chemical union of 2 or more elements.
Decompose
2 marks
If a substance decomposes, it breaks down into simpler compounds or elements.
Food chain
3 marks
A sequence (usually shown as a diagram) of feeding relationships between organisms
- showing which organisms eat what and the movement of energy through trophic levels.
Inorganic
1 mark
Not derived from living matter.
Molecule
2 marks
A collection of 2 or more atoms held together by chemical bonds.
Organic
1 mark
Derived from living matter.
Secrete
2 marks
To release a substance, in this case an enzyme.
Nutrient Cycles
6 marks
Within an ecosystem;
Nutrients - begin as simple inorganic compounds (CO2 and nitrate ions)
- taken in by a plant and used to make more complex biological molecules.
Molecules - passed along the food chains.
When plants + animals die = complex biological molecules decomposed.
Where do nutrients begin as simple inorganic compounds?
1 mark
Within an ecosystem.
What do nutrients begin as in the ecosystem?
2 marks
Simple inorganic compounds.
CO2 + Nitrate ions
What are taken in by a plant + used to make more complex biological molecules?
(2 marks)
Simple inorganic compounds
CO2 + Nitrate Ions
What take in Simple inorganic compounds (CO2 + Nitrate Ions)?
(1 mark)
A plant
Why does a Plant take in Simple Inorganic Compounds such as CO2 + Nitrate Ions?
(2 marks)
To make more Complex Biological Molecules
- that can be passed along the food chains.
How do Complex Biological Molecules transfer to animals if originally produced by plants?
(1 mark)
Passing along the food chain
in food consumed by animal
What happens to Complex Biological Molecules once an Organism dies?
(2 marks)
They decompose
- plants can then absorb + reuse these simple compounds, completing the cycle.
Decomposition of organisms
3 marks
The process by which bacteria + fungi break dead organisms into their simple compounds
- after they have decayed.
Decay
2 marks
The process in which dead organisms are broken down into smaller pieces
-organisms such as earthworms are involved in this process.
Decomposing bacteria + fungi are described as…
1 mark
Saprophytic
What do plants do with the Simple Compounds produced after Complex Biological Molecules are decomposed?
(2 marks)
Absorb + reuse the compounds.
Why are decomposing bacteria + fungi described as saprophytic
(1 mark)
because of the way they break down dead organic matter.
Saprophytic nutrition involves:
4 marks
Bacteria/fungi secreting enzymes out of their cells into the soil or dead organism
- enzymes digest the organic material (extracellular digestion)
- products of digestion are absorbed by the bacteria/fungi.
The enzymes digest the organic material during ‘Saprophytic Nutrition’
what is the name of this process?
(1 mark)
Extracellular Digestion
Where do the Enzymes digest organic matter during the Saprophytic process? (Extracellular digestion)
(1 mark)
Outside the cells.
Extracellular digestion;
Explained
(6 marks)
Process in which Saprobionts feed by secreting enzymes through the cell membrane onto food
- Enzymes catalyse the digestion of food into molecules small enough to be taken up by passive Diffusion, transport of phagocytosis.
Extracellular digestion;
Simplified
(2 marks)
Enzymes digest organic material outside the cells.
Humus
2 marks
Organic content of the soil formed from decomposing plants + animals.
Bacteria/fungi secretes, what, out of their cells into the soil or dead organism - in the Saprophytic process?
(1 mark)
Enzymes
What are the products of digestion absorbed by - during the Saprophytic process?
(2 marks)
Bacteria/fungi
Ideal conditions for decomposition (so it happens quickly)
3 marks
Temperature is warm
Enough moisture
Decomposing organism has a large surface area.
What is the ideal temp for decomposition?
1 mark
Warm
What conditions cause the rate of decomposition to decrease?
1 mark
Anaerobic conditions
little/no O2 available - E.g waterlogged soil
What is a major component in Carbs, Fats + Proteins?
1 mark
Carbon
Carbon is a major component in
3 marks
Carbs, fats + proteins.
The Carbon Cycle
3 marks
Involves the exchange of Carbon between living organisms (biotic) + their atmosphere (abiotic).
In the cycle, what is constantly removed from, + returned to, the environment?
(1 mark)
Carbon
A balanced ______ cycle is essential?
1 mark
Carbon
Processes involved in the carbon cycle are:
8 marks
- Photosynthesis
- Feeding
- Respiration
- Fossilisation
- Combustion
- Excretion
- Egestion
- Decomposition
Photosynthesis in the Carbon Cycle;
3 marks
Plants absorb CO2 from atmosphere + form it into sugar, starch + other organic compounds.
This is the only process in the cycle that decreases the level of CO2 in the atmosphere.
Feeding in the Carbon Cycle;
2 marks
Moves carbon in the form of biological molecules along the food chain.
Respiration in the Carbon Cycle;
3 marks
When living organisms (plants, animals and decomposers) respire they release CO2 into the atmosphere
-this is a form of excretion.
Fossilisation in the Carbon Cycle;
4 marks
If conditions are not favourable for the process of decomposition - dead organisms decay slowly or not at all.
These organisms build up + if compressed over millions of years, can form fossil fuels (coal, oil or gas).
Combustion in the Carbon Cycle;
2 marks
Burning of fossil fuels releases stored CO2 into the atmosphere.
Excretion in the Carbon Cycle;
2 marks
When waste is removed from the body (urine)
- this excreted material can be broken down during the process of decomposition.
Egestion in the Carbon Cycle;
3 marks
Removal of faeces from an animal that will contain carbon
- this egested material can be broken down during the process of decomposition.
Decomposition in the Carbon Cycle;
3 marks
When complex, carbon compounds in dead organisms, urine + faeces are broken down into simpler carbon compounds - by bacteria or fungi.
