What would happen to the Earth if the ozone layer were destroyed?
Our natural sunscreen, known as Earth's ozone layer, absorbs and blocks the majority of the sun's UV radiation. Without this barrier in place, all of the radiation would reach Earth, damaging the DNA of plants and animals, like us humans. Skin cancer rates would soar, but we might not even live long enough to experience that cause of death.Within days of the ozone layer's disappearance, many plants would die. The intensity of the sun's radiation would make photosynthesis — a process by which plants convert light energy into chemical energy to fuel their growth — an impossibility for all but the largest and slowest-growing florae. And even these holdouts, primarily massive trees, would eventually die, too. Without plants, the food chain would collapse. Herbivores would starve. Omnivores and carnivores could feed off their bodies for a time, but their food supply would dwindle and cause widespread extinction.So where is the ozone layer, exactly, and how does it work? A layer of ozone gas acts as a shield encircling Earth, and exists between 9.3 (15 kilometers) to 18.6 miles (30 kilometers) above its surface. As one might suspect, the ozone layer is filled with ozone, also known as [math]O_3[/math][math] [/math]or trioxygen. Ozone is created when oxygen molecules ([math]0_2[/math]) are split by the sun into a duo of free-ranging oxygen atoms. When one of these free atoms bonds with an [math]0_2 [/math]molecule, an [math]0_3 [/math]molecule -- ozone -- is created.Despite its protective powers, ozone isn't necessarily stable, and it doesn't take much to reduce ozone to its base elements. Take chlorofluorocarbons (CFC's), for example. When these synthetic chemicals, once used as refrigerants and aerosol-spray propellants, travel to the upper atmosphere they begin a chain reaction that spells disaster for the ozone layer. The CFC's are broken down by ultraviolet light and, as a result, release free chlorine atoms that attract oxygen atoms from ozone molecules. And what happens when you take an oxygen atom from ozone? It becomes oxygen. In this way, CFC's can make quick work of the ozone layer, which is why they have been placed under ever-tightening regulations over the past several decades, with a goal of eliminating their use completely later this century.So, I request everyone to do WHATEVER is in your right to save ozone.Reference To: howstuffworks, Google
What are the main differences between plant and animal cells?
The difference between plant and animal cell is very basic as well as important thing to know from the biological point of view. Plant and animal cell are similar in many ways as they both are eukaryotic cells. Since these are eukaryotic cells so they both have the cell membrane and cell organelles, like the nucleus, mitochondria and endoplasmic reticulum in common.Now the key difference between plant and animal cell are-.A plant cell has the cell wall which is made of cellulose whereas animal cell doesn’t have cell wall.Another comparison can be made based on their shape. A plant cell has fixed rectangular shape whereas animal cell has generally round and irregular shape.A plant cell has one large shape vacuole which covers the large part of a cell, the animal cell has one or more vacuole which is much smaller then plant cell. The vacuole is generally a storage unit used to store water in the cell.The animal cell doesn’t have chloroplast. A plant cell has chloroplast as they make their own food by photosynthesis. It also imparts a green color to the plants.Nucleus lies on the one side of peripheral cytoplasm in plant cell whereas nucleus lies in the center of the animal cell.for more detail Plant Cell vs Animal Cell | What's the difference?