7.1 Adaption, interdependence and competition Flashcards
Population
A number of individuals of the same species living in the same area at the same time.
Community
Multiple populations of different species living and interacting in the same area.
Competition
If a group of organisms all need the same resource in order to survive and reproduce but there is a limited amount of the resource available, they are said to compete for the resource.
Competition can be between members of the same species (intraspecific competition) or between members of different species (interspecific competition).
Adaptation
If an organism has certain features, behaviours or other characteristics that help it to survive and reproduce in its habitat, it is said to be adapted to its habitat.
Ecosystems
An ecosystem is the interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment.
Ecosystems can vary greatly in size and scale. Some ecosystems are small - a single tree can be seen as an ecosystem.
Some ecosystems are very large - the whole of Antarctica can be seen as one ecosystem.
Interaction within an ecosystem
In order to survive and reproduce (have offspring), organisms need certain resources from their surroundings (from the ecosystem they are living in).
This means that members of a species will often interact with members of its own species or other species.
Competition in plants
Light - plants require light for photosynthesis in order to produce glucose which provides them with energy for growth.
Space - plants require space above soil so leaves can absorb maximum sunlight and below soil so roots can absorb water and mineral ions.
Water - water is essential for photosynthesis and therefore plant growth.
Mineral ions - plants require various mineral ions to make chlorophyll and protein.
Competition in animals
Food - food provides animals with the energy they require for growth and reproduction.
Mates - animals require mates in order to reproduce and pass on their genes.
Territory - this is an area of habitat that provides and individual with resources such as water, food, shelter and mates.
Interdependence
Within a community, each species depends on other species for food, shelter, pollination, seed dispersal etc.
If one species is removed it can affect the whole.
This is called interdependence.
A stable community is one where all the species and environmental factors are in balance so that population sizes remain fairly constant.
Types of abiotic factors
Abiotic factors are non living.
Some factors are: light intensity, temperature, moisture level, soil pH, mineral content, wind intensity and direction, co2 levels, oxygen levels.
Types of biotic factors
A biotic factor is a living factor.
Some examples are: availability of food, new predators, new pathogens, competition.
Adaptations to cold regions
Animals here often have a small surface area: volume ratio to minimise heat loss to their surroundings (rounded shape of penguins/seals, small ears of the Arctic fox).
A thick layer of fat (seal blubber) or fur (polar bears) insulates against the cold.
These are examples of structural adaptations.
Adaptations to hot regions
Some desert animals have specially adapted kidneys which produce very concentrated urine, helping the animal to retain water - this is a functional adaptation.
Some are only active in the early mornings, late evenings or at night when it is cooler - this is a behavioural adaptation.
Some animals have structures to increase their surface area: volume ratio to aid heat loss (large ears of African elephants) - these are structural adaptations.
Extreme adaptations
Some organisms live in environments that are very extreme, such as at very high or low temperatures, pressures, or high salt concentration.
Organisms that can live in extreme environments are called extremophiles.
An example of habitats where extremophiles are found are deep-sea volcanic vents, where the conditions are extremely hot, under high pressure and there is no sunlight.
Bacteria called chemoautotrophs survive by using inorganic chemicals to obtain energy (rather than using sunlight in photosynthesis as photoautotrophs do).
