Science Labs Quiz: Sampling
what are the steps you would use to make a sample of all of the dandelions in your yard?
1. divide yard into grid 2. randomly choose grids to sample 3. collect data and calculate average 4. multiply average by total boxes/grids
what are factors that caused an increase in the rabbit population?
Plentiful food, spring coming early, more rabbits moving into the area
what are the steps of random sampling?
add up the numbers, divide by the amount of numbers given, and multiply by the amount of squares in the grid
what is a census?
an official count or survey of every organism in a population
why is population sampling more effective when there is even dispersion instead of clumped dispersion?
because clumped dispersion can inflate or deflate the estimate
why do scientists need to estimate the size of a population?
because it is difficult to find the actual size of a population because organisms will move around and some may be missed
why can't scientists just go into the forest and count the amount of sunflower plants?
because there is room for error, and random sampling saves money, time and effort
why is the mark and recapture method used instead of counting all of the organisms in a population or instead of using the random sampling method with fish in a pond?
because unlike plants, organisms move around, so the other methods do not work
what are the options an organism has if they have a low or inadequate food supply?
die/go hungry, move out of the area, or eat a different species of animal (one that they might not ordinarily eat)
in the predator/prey lab, what two animals were used?
foxes (predator), rabbits (prey)
what happened to the rabbits when the pheasant population decreased?
foxes ate more rabbits, so the rabbit population decreased
what are factors that decreased the rabbit population?
harsh winter, inadequate food supply, disease, and more foxes eating rabbits
what will happen if a population keeps getting exponentially higher?
it will eventually get overpopulated then resources run out and some will die since they can't get what they need
what are factors that caused a decrease in the fox population
low food supply, hunters, disease among rabbits, foxes moving out of the area
factors that will cause an increase in the fox population
plentiful food, foxes moving into the area, large litters, eating pheasants as well as rabbits
why do biologists use sampling?
so that they can get the amount of species in an area
why do scientists use random sampling?
to estimate the size of a population without taking a census
why was a paper-slip method used to select the grid segments in the random sampling lab?
to keep it random and eliminate bias
