<span>is operated by the U.S. Coast Guard</span>
Answer:
When cycling of matter in the ecosystems is disrupted, the whole ecosystem will be adversely affected. Matter includes living organisms such as plants, animals and microorganisms while non living things such water, air and nutrients etc. If plants are removed from the ecosystem system, then the whole ecosystem is destroyed because plants are the producer which make food for herbivores. These herbivores are eaten by carnivores and so on.
Answer:
protected; increase
Explanation:
Ozone is composed of trioxygen which is highly reactive gas compared to dioxygen. Ozone layer is present in stratosphere and troposphere and protect the humans from ultraviolet radiations but it may be toxic if inhaled. Ozone can be broken down into molecular oxygen by chlorine and bromine atoms.
A hole was discovered in ozone layer in 1982 and scientist believed that it could be dangerous for human health. The compounds involved in depletion of ozone are mainly Chlorofluorocarbons (CFS) and (HFCS). Then a global agreement was signed in 1987 which leads to prohibition of use of all chemicals that are involved in depletion of ozone layer. The problem of ozone depletion is solved by the agreement and ozone hole started to recover it from 2000.
But recent reports showed that the alternative chemicals used to protect the depletion of ozone layer began to trap the heat inside the earth like greenhouse effect. Now scientists are in search of chemical that can prevent both ozone depletion as well as global warming.
Answer:
Explanation:The seasons are caused as the Earth, tilted on its axis, travels in a loop around the Sun each year. Summer happens in the hemisphere tilted towards the Sun, and winter happens in the hemisphere tilted away from the Sun.
Answer:
The behavior of chromosomes during meiosis and fertilization is responsible for most of the variation that arises in each generation. Three mechanisms contribute to genetic variation arising from sexual reproduction: independent assortment of chromosomes, crossing over, and random fertilization.
