B6: Ecosystems Flashcards
What are food chains?
Food chains show the feeding relationships in a habitat.
What is a pyramid of numbers?
Pyramids of numbers are charts that show the numbers of living organisms at each step in a food chain. There are usually few organisms the higher up the chain/ pyramid you go.
What do the arrows in a food chain show?
The arrows in a food chain show the direction that the energy is flowing.
Why are there a fewer organisms at the top of the food chain compared to at the bottom of the food chain?
There are fewer organisms at the top of the food chain because at each stage of the food chain, energy is lost so by the time it gets to the top of the food chain, there is very little energy left.
How is most of the energy used up in a food chain?
- energy released by respiration is used for movement and other life processes, and is eventually lost as heat to the surroundings
- energy is lost in waste materials, such as faeces
What is the order of the food chain?
- Producers –> primary consumers –> secondary consumers –> tertiary consumers
What is biomass?
Biomass means the mass of living material at a stage in a food chain. The biomass goes down as you go from one stage to the next, just like the amount of energy.
Name an example of an animal and non-animal parasite
- headlice - they bite other animals such as humans in order to feed off their blood
- mistletoe - the roots of mistletoe grow into the veins of the host tree to absorb nutrients and minerals.
What is a biome?
A biome is a community of plants and animals that have common characteristics for the environment they exist in.
What is meant by ‘ecosystem’?
An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.
Define ‘biotic’ and ‘abiotic’ factors
Biotic factors - the living things in an ecosystem
Abiotic factors - non-living things in an ecosystem
What does ‘population’ mean?
All the organisms of the same group or species, which live in a particular ecosystem or habitat
Briefly describe how you would use a quadrat.
Step 1: Place your quadrat at random.
Step 2: Count the number of plants present for the nominated plant species and record these numbers.
Step 3: Repeat the above process until you have covered ten areas using your quadrat.
Step 4: Add up the total number of plants you recorded for each species and divide by ten to give you the mean average. Multiply this number by the area of the field.
Name 3 ways we can conserve (protect) species and habitats.
- Captive breeding programs (zoos)
- Fishing quotas
- Protected areas e.g National parks and nature reserves
What word describes the need for a living thing in an ecosystem to rely on the other living and non-living things?
Interdependence
