Northern lights or auroras can be seen within the sub-layer.
a. ozonosphere
b. ionosphere
c. exosphere
d. troposphere

Which group is noted for the independence of gametophyte and sporophyte generations from each other? a) ferns b) mosses, hornworts, and liverworts c) charophytes d) angiosperms e) gymnosperms

Use the drop-down menu to match the following definitions to the corresponding terms. the total variety of organisms that live in the biosphere a group of organisms that breed and produce offspring that can breed all of the biotic and abiotic factors in an area

Which of the organisms listed below performs nitrogen fixation? a. legumes b. plants c. bacteria d. fungi