Answer to Question 1
With the greenhouse effect,visual-wavelength sunlight can enter a greenhouse and heat its contents, but the interior radiates infrared radiation but cannot get out. The same process can heat a planet's surface if its atmosphere contains greenhouse gases such as CO2 . The concentration of CO2 in Earth's atmosphere as measured in Antarctic ice cores remained roughly constant for thousands of years until the beginning of the Industrial Revolution around the year 1800 . Since then it has increased by more than 35 percent. Evidence from proportions of carbon isotopes and oxygen in the atmosphere proves that most of the added CO2 is the result of burning fossil fuels.
Answer to Question 2
hydrogen; helium
helium; hydrogen
The effect of a double bond on the shape of fatty acids
First-pass effect: (a) drugs are absorbed; (b) drugs enter hepatic portal circulation and go directl
A sod house in North Dakota, 1896. Individual “bricks” of sod were hewn from the ground and stacked
Systems of humans
Electricity production accounts for 25% of greenhouse gas emissions
The ancestral and modern-day tomato. (b) Phenotypic effect of the fw2.2 transgene in the tomato