Chapter 3.5 Human Impact on the environment Flashcards Preview

FULL COURSE National 5 Biology > Chapter 3.5 Human Impact on the environment > Flashcards

Flashcards in Chapter 3.5 Human Impact on the environment Deck (11):

The increasing human popualtion requires an

increased food supply


Methods of increasing food supply have included the use of;

fertilizers, pesticides, biological control and genetically modified (GM) crops.


Fertilizers can leach from fields into freshwater increasing the effects of

algal blooms


When algal blooms dies they are decomposed by aerobic bacteria which

multiply and reduce the oxygen concentration in the water


Pesticides can accumulate in the bodies of

organisms and so build up along the food chain


Toxicity levels of pesticides in the bodies of carnivores to the extent that the animal

or its reproduction is damaged


The presence, abundance or absence of

indicator species can reveal information about the environment and level of pollution present.


Biological control relies on natural solutions to

pest problems such as making use of natural predators or parasites


Crop species can be genetically modified to increase their yields without the need for

fertilizers or pesticides


Biological control and GM crops are alternatives to

intensive farming methods


Using biological control and GM crops rather than intensive farming methods could result in

less damage to the environment