Ocr A Level Biology Biodiversity Questions And Answers 100% Verified A+ Guaranteed

Disadvantage of stratified sampling {Ans: Unusable when you can't classify every member of the population into a sub group.}How do higher temparatures and less rainfall affect biodiversity? {Ans: Non drought resistant species of plants will die out. animals that feed on them will die too. drought resistant plants (xerophytes) will become more dominant. animals that used to feed on hydrohphytes will be replaced by animals who feed on xerophytes.}Sampling is necessary because we can't usually gather data from the entire population due to: {Ans: Large/inaccessible population (it's impossible in most cases to study the actual entire population) Lack of resources Sampling is the only method available when data gathering process damage the item from which we require data.}Pitfall traps {Ans: - Used to catch small, crawling inverterbrates e.g. beetles, slugs, spiders etc - Hole dug into ground which insect falls into. - Must be deep enough so that the insects cant crawl out. - Trap must be covered so it doesnt fill up with rainwater}Frame quadrat {Ans: - Square frame divided into equal grids - Type and number of species within each grid is recorded}Methods of sampling plants (2) {Ans: - Frame quadrat -