Living things need air, food and water because they are essential to the chemical processes that provide organisms with energy and keep them alive. These processes are collectively known as metabolism. The nutrients found in food, the oxygen found in air and the solvent property of water are indispensable components of metabolism.Know More
The biological functions that keep organisms alive are forms of work, and all work requires energy. Because energy cannot be created, living things have to obtain it from a source. That source is the food they eat. Food is filled with different chemical compounds that provide energy when chemically broken down. Individual nutrients perform specific functions within an organism. For instance, carbohydrates are the body's main source of fuel, fats are critical for cell structure and proteins help make hemoglobin.
Water is a solvent that is necessary for many chemical reactions in the body, including metabolism. It takes part in the breaking down of nutrients, but its importance is even more basic and far-reaching. Cell cytoplasm is mostly made of water. Without water, cells lose their structure and experience severe damage.
Air is important because it has oxygen, a critical component in cellular respiration, the metabolic process by which living things obtain energy. Organisms combine oxygen with glucose to produce ATP (energy).Learn more about Biology
Volcanoes are not, in any meaningful sense of the word, alive. Volcanoes are rocky structures formed by the ejection of molten rock through weak spots in the Earth's crust, according to Oregon State University. Apart from some of the gases they expel, they are primarily silicon-based, not carbon-based.Full Answer >
Viruses are generally not regarded as living organisms as they lack the cellular machinery required to survive on their own. This distinction is somewhat tenuous as viruses carry their own unique genetic material and are capable of evolving, but the commonly accepted definition of "life" requires the presence of a metabolism.Full Answer >
Living things are organisms that display the key characteristics of life. These characteristics include the ability to grow, reproduce, take in and use energy, excrete waste, respond to the environment, and possess an organized structure more complex than that of non-living things.Full Answer >
The energy used by all living organisms on earth can be traced back to the sun. The sun produces heat and light energy which helps in maintaining temperatures on earth and creates daylight. Plants, which are sometimes referred to as producers, use light energy in a process called photosynthesis to create nutrients or energy.Full Answer >