Question | Answer |
What is a habitat? | It is where an organism lives. |
What does community consist of? | all the animals/plants living in one area |
What is a population? | All the members of one particular species |
What is an ecosystem made up of? | living (community) and non living (habitat) parts |
What are biomes? | Large ecosystems |
How many biomes are there in the world? | There are 9 biomes worldwide dependent on the climate (temperature and rainfall) e.g. Tundra, Sahara |
What characterizes a particular biome? | Its specific flora (plants), fauna (animals) and climate (rainfall and temperature). |
Why should biomes be preserved? | In order to have a stable planet as they increase the biodiversity |
What is biodiversity? | It is the variety and abundance of organisms present |
What are biomes affected by? | biotic, abiotic and human factors |
Which factor has the biggest impact on biodiversity of a biome? | human factor. |
What are biotic factors? | They are living factors and include predators and grazing |
What are abiotic factors? | They are non living factors and include moisture, light intensity pH and temperature |
Predator and prey numbers are | the opposite of each other and can be shown as waves on a graph. |
Low grazing leads to | low biodiversity as dominant plant species is not kept in check |
Medium grazing leads to | an increase in biodiversity as dominant plant species are eaten, allowing weaker species to grow. |
High grazing leads to | low biodiversity as only the dominant plant species can tolerate very high grazing. |
Human impact factors are: | exploitation (overfishing/hunting), deforestation, poaching and pollution |
Pollution by burning fossil fuels | increases the sulfur dioxide concentration in the air. |
What is an indicator species? | A species that indicates the level of pollution by its presence/absence. |
An example of indicator species would be | lichen. They only grow where there is little air pollution |
What causes algal bloom? | Fertiliser dissolving in rain water and being washed into lochs, which increases the nitrate concentration |
What follows an algal bloom? | Decomposer bacteria feed on the algae and reduce the oxygen levels in the water (respiration) causing fish to die. |