Jiho Biology Organisms and their environment

decomposers..

obtain energy by breaking down oragnisms, faeces and excretory products.

explain why energy is non cyclic..

Energy is non-cyclic because it is lost as heat at each trophic level and not reusable, flowing unidirectionally from the sun through producers, consumers, and decomposers, and eventually dissipating into the atmosphere.

Energy is non-cyclic in an ecosystem because, unlike nutrients, it is lost as unusable heat at each step of energy transfer, following the second law of thermodynamics. ( basically says energy trasnfer cannot be perfect)

How is energy lost at each subsequent trophic level ***

As heat released during respiration
Unconsumed aprts of organisms
Undigested and indigestible matter egested by consumer
Waste products excreted by consumers
Organisms die without being consumed

WHAT IS 10 percent rule

90 percent energy is lost between each succeeding trophic level and only 10 percent of energy is trasnferred to the next

Advantage of short food chain ***

A short food chain means more energy is available to the final consumer as less energy is lost to the environment
If food chains are too long , there will not be enough energy availabel to support the final consumer
Talk about 90 10 rule

== More effcicient because more energy available

WHY IS CARBON IMPORTANT

enable enrgy flow in the form of carbon compounds
ensure continous suppply of co2 for photosynthesis

define carbon sink ***

A carbon sink is an area that stores carbon compounds for an indefinite period
It stores more carbon than ti releases

What makes ocean a carbon sink

it dissolved co2
and it stores fossil fuels in seabed

What makes trees a carbon sink

carbon is stored in tree
they form coal even after they die
long term storage of c

WHAT IS EUTROPHICATION ***

process where excess nutrients in water bodies lead to algae and water plants growing excessively
Untreated sewage and fertilisres

HOW DOES EUTROPHICATION HAPPEN **

the untreated sewage and fertilisers are washed by rainwater into waterbodies
The nitrates and phosphates of untreated sewage enhances the growth of algae and water plants
Multiplcation of algae population
Prevent sunlight and cause plants to die,=
1 . No food for fish
2. Decomposition of these dead stuff release co2 and use oxygen in the process to kill other animals

bioaccumulation is..

the accumulation of toxic substances in a consumer

biomagnificaiton is..

the increase in concentration of toxic subsatnces in teh bodies of organisms up the trophic level

Why is conservation important ( from syllabus ) **

maintenance of biodivesity and balanced ecosystem

e.g
Forest
important habitat for animals

Mangrove swamps
Protect low lying areas from flooding

Coral reefs
Important marine habitat

define carbon cycle

constant movement of carbon atoms between the atmosphere, oceans, land, and living organisms on Earth