Answer:
1. Earth's temperature is maintained by re radiated infra red radiation by green green house gases and slightly by water vapors in atmosphere. These gases prevent heat from escaping to outer space, so are functionally comparable to glass panel of green house. Thus, this heating effect is referred to as green house effect. Carbon dioxide is a green house gas so increased amount of this gas in the atmosphere will result in increased atmospheric temperature and global warming.
2. Three sources of atmospheric carbon dioxide are:
- Volcanic eruption
- Respiration by plants and animals
- Decomposition of organic substance.
Explanation:
- <u>Overall rise in temperature </u>of the Earth due to excessive amount of green house gases in atmosphere that trap heat radiating from Earth's surface is called Global warming.
- Global warming can cause melting of ice caps, alteration of seasons, destruction of forest and increase in deserts.
- Green house gases include carbon dioxide, methane, ozone, nitrous oxide, and nitrogen dioxide etc.
- Among all these gases Carbon dioxide is the major component that is responsible for global warming.
- Carbon dioxide is added to the atmosphere by burning of fossil fuels, volcanic eruption and respiration. But Burning of fossil fuels itself adds about 18 X 10¹² tonnes of CO₂ anually.
- Global warming has become a major environmental concern now and needs to be controlled immediately.
<span>The sequence is as follows:
c, d, a, b, f, g, e
The impulse starts at the SA node that has its own contraction rhythm (but can be faster or slower depending on other impulses or hormones). That impulse travels then through the atria and is slowed down by the atrioventricular septum except for a region in the right atrium called AV node where the impulse has continuity. The impulse travels then to the ventricles through the AV bundle. The impulse continues through bundle branches to other fibers: Purkinje fibers. These Purkinje fibers cause then a contraction that goes from the apex of the heart and rapidly through the ventricles.</span>
Plants and other autotrophs absorb nutrients from soil and water. Autotrophs are organisms that can make their own food. The most important nutrients they need are carbon, hydrogen, and oxygen. Other nutrients needed by plants are nitrogen, phosphorous, potassium, calcium, magnesium, and sulfur.
I think A sorry of I’m wrong but I researched the other options.
Although cells are diverse, all cells have certain parts in common. The parts include a plasma membrane, cytoplasm, ribosomes, and DNA. The plasma membrane (also called the cell membrane) is a thin coat of lipids that surrounds a cell.
Hope it helps ^^
