In most ecosystems, the original source of energy for the living things in the system is the sun.
Answer:
The pH of the soil, which is a measure of the acidity of the soil, governs to a large extent what is suited to and will grow well on a particular soil. Thus, agricultural crops, many of which go on to become our food, require soils in a particular pH range in order to produce their best yields. Both garden and wild flowers have a pH range in which they grow best. Similarly most organisms that live in the soil will operate in soils in a pH range that suits them. For example, one of the most common species of earthworms,has a strong preference for soils with a pH above 5.5 to just over 7.0. Other species of earthworm such as Allolobophora longa can tolerate pHs less than 5.5 but only down to about 4.5. Below pH 4.5 in Western Europe at least, there are usually few earthworms in the soil. pH also has an important effect on the availability of plant nutrients. Several nutrients become less available at the lower end of the pH range, i.e. below pH 5.5 and the availability of a few tails off significantly at pHs above 7.5. It is important that those who use the soil for purposes that depend on soil nutrients should be aware of the best pH range for key nutrients.
Explanation:
Answer:
Ball-and-stick models show the bonds between atoms, but not the relative sizes of atoms. Space-filling models show the relative sizes of atoms, but not the bonds between atoms.
Three levels of biodiversity: genetic, species and ecosystem
Answer:
B.) located in the photic zone and warm tropical waters with build up of many layers of dead cnidarians