Friday, October 24, 2014

summary questions

1 using an example describe why a population could not increse for ever.

because if population increases it may reach its carrying capacity and if that happens the ecosystem will run out of resources. for example if wolfs eat up all the bunny's they will decrees because they will run out of food in this case.

2 what are 2 factors that determine whether a population increases or decreases. 

the first factor would be lack of resources for example if a species docent have enough food to live they population number will decrease, but if a species has too much food their population will increase. 

the other factor would be over population of predators if there are too many wolves that eat the food the food or pray population will decrease , but if there are too little predators then the prey population will increase.

3 give a reason why the human population of earth has continued to increase so much for the past hundred years.

because we are learning to eat every thing and we have a over populated amount of resources but in one moment that will balance out 

Monday, October 20, 2014

symbiosis

definition symbiosis: Is a close relationship between two species

types of symbiosis:
Mutualism in this relationship both species benefit one another for example bees and flowers the flowers need the bees because they polonaise the flowers so that they can reproduce and the bees need the flower because the flower gives them nectar to make honey.

Commensalism in this relationship one species benefits and the other is not helped by no one but not harmed. like for example the a person cooks meal for someone and that person eats it the cooker is not getting harmed or helped  but the consumer is getting helped.

parasitism in this relationship one species is benefited and the other is harmed for example mosquitoes and humans the mosquitoes bite humans and use blood for energy and humans get harmed because they can get a sickness.