B2d Flashcards
Why do organisms compete for mates
Because their species will die out if its members don’t breed and reproduce; the males will compete with other males of its species.
Why is there competition for food
Animals of different species eat the same food, so they will compete for it and will usually ‘win’ an area of land for hunting for food. When a species reproduces(eg a cheetah), it’s offspring (cubs) must move away so that they aren’t competing with their parents / family
What is an ecological niche
An organisms role in an ecosystem. E.g. a squirrels ecological niche is to live in the woods and eat acorns
What does interspecific mean
Competition between 2 DIFFERENT species, eg a red squirrel and a grey squirrel
What does intraspecific mean
Competition between the same species, eg 2 grey squirrels
Why does intraspecific competition have a bigger effect on the population
Because animals of the same species have the same ecological niche
What does mutualism mean
A relationship in which both animals benefit
What does a predator-prey relationship mean
The number of one effects the number of the other. Eg with badgers (predator) and shrews (prey). When there are lots of shrews, more badgers can reproduce to make more young. The next year, with more badgers, they eat more shrews than usual, resulting in less shrews that year etc.
What do parasites, like tapeworms, do to its host
They take food away so it can grow. It is unlikely to kill it’s host, however with a tapeworm in a human, they are likely to lose weight
What does cyclic fluctuation mean
The rise and fall of a population (usually depending on the predator-prey relationship or lots/lack of food)
Why does an organisms population size change all the time
They will immigrate and emigrate to a habitat that’s most suited to them. E.g. Birds will stay in Britain during summer because there’s lots of food, where as in winter they fly south because the cold means that there’s little food left in Britain
