Chapter 5: Higher Level Ecology Flashcards
what is a distorted pyramid of numbers?
when the pyramid does not have the largest number of organisms at the bottom
what is an inverted pyramid of numbers?
when the pyramid starts the with smallest number at the bottom and gets bigger
what are the 4 factors that control population?
competition
predation
parasitism
symbiosis
what is competition?
when organisms of the same or different species fight for the same resources that are in short supply e.g. shelter, food
what are the kind of competition is there?
intra-specific competition
inter-specific competition
what is inter-specific competition?
it is between members of different species
what is intra-specific competition?
it is between members of the same species
what are the two types of competition and explain them?
contest competition - involves an active physical confrontation between two organisms - one winner
scramble competition - each organism tries to acquire as much of the resource as possible - they both win but will soon run out of resource
what is predation?
the act of some animals capturing and killing other animals for food
what is a predator?
an animal that hunts, captures, kills other animals for food
what are 4 adaptations of predators?
keen senses and sharp teeth
change diet to suit prey availability
live and hunt in packs
camouflage
what is prey?
an organism that are hunted and eaten
what are 4 adaptations of prey?
plants may have thorns, stings or spines
nasty taste when eaten e.g. giant hogweed
faster than predator
camouflage
what does a graph representing predator/prey relationship look like?
predation initially increases the number of predators and decreases the number or prey
but when one decreases so does the other and when one increases so does the other
this cycle repeats itself
why does the population of prey and predator never go to zero?
the species may become extinct