Answer:
There is no video but ecological relationship will be defined on a general note and it is not always beneficial to organisms.
Explanation:
In an ecosystem, organisms of the same or different species tend to interact with one another. This interaction is referred to as ECOLOGICAL RELATIONSHIP between the involved organisms. An ecological relationship can be of different types depending on the effect.
SYMBIOSIS is an ecological relationship between two organisms that interact together. SYMBIOSIS can either be mutualistic (both organisms benefit), parasitic (one organism loses and one gains), or commensalistic (one organism benefits and one neither benefits or loses). Another ecological relationship is PREDATION, where one organism called the PREDATOR feeds on part or all of another organism called PREY in order to obtain energy.
As stated above, some of the organisms involved in an ecological relationship benefits while others lose. Hence, it is not always a beneficial relationship to organisms.
Layer that is 0.2 to 1.1 percent of Earth's total diameter is the thinnest layer of the Earth- Crust.
So, the correct answer is: oxygen and silicone. The crust consists of tectonic plates (in relative motion one from another) and has 5–70 km (~3–44 miles) in depth. The most abundant elements of this layer are: oxygen-46.6 percent by weight; silicon-27.7 percent; aluminum-8.1 percent; iron-5 percent.
Accumulation of substances such as pesticides or other chemicals in an organism
I believe that the youth movement originated with the baby boomers, the huge generation born after the world war II. By 1970, 58.2 % of the population in America was under the age of 35 years. The economic boom of the 1950s meant more families could afford to send their children to College. College life gave the young people a sense of freedom and independence. It was on college campuses across the nation that youth protest movements began and reached their peak.
