#1
Which gas was likely absent in Earth's early atmosphere?
#2
What is the primary component of Earth's atmosphere by volume?
#3
Which layer of Earth's atmosphere is closest to the planet's surface?
#4
What is the main source of atmospheric oxygen today?
#5
Which layer of Earth's atmosphere contains the ozone layer?
#6
Which gas is most abundant in Earth's atmosphere after nitrogen and oxygen?
#7
What process contributed to the formation of oxygen in Earth's atmosphere?
#8
Which era saw a significant rise in oxygen levels in Earth's atmosphere?
#9
What is the primary function of the ozone layer in Earth's atmosphere?
#10
What event likely led to the formation of Earth's early atmosphere?
#11
Which gas is considered a greenhouse gas in Earth's atmosphere?
#12
Which geological era marks the beginning of significant oxygen accumulation in Earth's atmosphere?
#13
Which scientist is credited with proposing the Gaia hypothesis, which suggests that Earth functions as a self-regulating system?
#14
What is the name of the event that led to the mass extinction of dinosaurs, changing Earth's atmosphere significantly?
#15