Ecology - Adaptations, Interdependence & Competition Flashcards
What is a species?
A species is a group of organisms able to interbreed and produce fertile offspring
What is a “population”?
The total number of all the organisms of the same species that live in a particular geographical area
E.g.: the human population is the number of all the humans on earth.
What is a “community”?
A community is group of two or more populations of different species that live at the same time in the same graphical area.
What is “competition” between organisms?
What are the 2 different types?
The contest between organisms within a community
1) Interspecific = between different species
2) Intraspecific = between two organisms of the same species
What happens to little plants on the floor if a large tree with a canopy falls to the floor?
The small plants and seedlings will grow, as there is no longer competitions from the big tree.
Light can now reach the small plants on the floor for photosynthesis and more nutrients are available so the little plants can grow
What is “Interdependence”
All species that live in a community depend on each other.
E.g.: sharks rely on smaller fish for food. The smallest fish eat photoplankton which are at the bottom of the food chain because they photosynthesise.
Why is it important for the number of prey and predators to stay similar?
It keeps the community stable. If the number of predators increase, the number of prey decrease and the competition becomes more fierce.
What are “abiotic” factors?
Abiotic factors are non-living parts of the environment that are physical or chemical
Give some examples of abiotic factors
1) Light intensity - plants need it for photosynthesis to grow. Polar regions face away from the sun so it is difficult for plants to grow here.
2) Water - also needed for photosynthesis, e.g.: plants struggle to grow in deserts
3) The pH of soil & minerals in it. Some plants are adapted to live in nutrient-poor soils.
How do gardeners use abiotic factors to help grow their plants?
They put lime powder (CaCO3) to make it more alkaline. This helps plants absorb major nutrients such as nitrogen and phosphorus so they can make proteins and grow more.
What are “biotic factors”?
Biotic factors are living factors or related to living organisms
Give some examples of biotic factors
1) Predators - a biotic factor that can affect a community. If we introduce a new predator, then the number of prey will decrease.
2) Diseases - Introducing a new disease can have an effect on populations in a community. E.g.: dutch elm disease killed 25 million elm trees in the UK
3) Competing species - Introduction of one species which can outcompete another, e.g.: the grey squirrel has outcompeted the red squirrel, leaving very few left.
What allows organisms to outcompete others and provide them with an evolutionary advantage?
Adaptations - which can be structural, behavioural or physiological.
How are polar bears adapted to live in extreme cold (-89 degrees)?
They have small heads and ears to reduce heat loss.
They have a thick layer of fat and fur to keep warm.
How have bacteria adapted to live around deep-sea hydrothermal vents?
They have evolved to feed of chemical released by the vents - e.g.: sulphur compounds, which are toxic to most other life. Therefore they can exist where other organisms can’t.
