P2-Topic 7- Ecology 2022 Flashcards
(34 cards)
Define population
A species that occupy the same habitat
Define habitat
The place in which an organism lives.
Define community
Populations of different species interacting
Define ecosystem
The interactions between the biotic and
abiotic factors in an area.
What do food chains show?
Food chains show the feeding relationships of
different organisms and the flow of energy between
the organisms
Define biomass
The total mass of living material
What are trophic levels?
The stages in a food chain
What do arrows in a food chain represent?
The direction of biomass transfer
What types of organisms are primary producers?
Photosynthetic organisms like green plants and algae that trap energy from
the sun.
An organism that makes its own food
What is a predator and prey 2
pred- A consumer that kills and eats other
animals.
prey-An animal that is killed and eaten by
another animal
Describe the pattern of predators and prey in a stable community
The numbers of predators and prey rise and fall in cycles
Why are producers the first trophic level? 2
● Producers provide all biomass for the food
chain (production of glucose via
photosynthesis).
● The rest of the food chain involves the transfer
of this biomass.
What piece of apparatus is used to measure the
abundance and distribution of organisms in an area?
quadrat
What piece of apparatus is used to study
the distribution of organisms across a
gradient?
Belt transect
How is the arithmetic mean calculated?
Sum of each number of each organism
/the total number of each type of organism.
Describe how materials cycle through the living and non-living components of an ecosystem 4
● Organisms take in elements from their surroundings e.g. soil, air.
● Elements converted to complex molecules which become biomass.
● Elements transferred along food chains.
● Elements returned to environment during excretion and
decomposition of dead organisms.
Give 3 molecules which are cycled through
ecosystems
Oxygen, carbon dioxide and water
Describe the carbon cycle 4
- Plants fix carbon dioxide into organic molecules during photosynthesis.
- The organic carbon-containing molecules are passed onto organisms
that eat the plants. - Carbon dioxide is released back into the atmosphere by respiration
from animals and plants. - Burning fossil fuels also releases carbon dioxide into the atmosphere.
Why is the carbon cycle important?
Carbon-containing molecules such as
glucose are important for living organisms to grow and provide energy
for vital functions within cells
Describe the water cycle 4
- Water from lakes and oceans evaporates.
- The evaporated water condenses into clouds and returns to earth as precipitation.
- The water from precipitation is useful for life on land.
- The water then returns to rivers and oceans through
surface runoff.
Why is the water cycle important?
Living organisms require water and the
water cycle provides organisms on land
with a continuous supply of water
Why are microorganisms important for the cycling of
materials through an ecosystem?2
Microorganisms (bacteria and fungi) return carbon to the environment by releasing carbon dioxide through respiration while they decompose dead matter
.The decomposition of dead matter in soil returns mineral ions to the environment for other organisms to use e.g. plants use mineral ions for growth
decomposition
4.7.2.3
62 flash
Decomposition
breakdown of dead material into simple organic matter
