There are five main symbiotic relationships: mutualism, commensalism, predation, parasitism, and competition.

The symbiosis relationship between leeches and humans is known as parasitism.

Explain the parasitic relationship between a fish and a leech. Fish live in water and have blood with nutrients in it. Leech also live in the water and suck blood from animals that live in the water. Barnacle needs a hard, flat, open surface to attach and live on.

Commensalism is a symbiotic relationship in which one species benefits while the other species is not affected. One species typically uses the other for a purpose other than food. For example, mites attach themselves to larger flying insects to get a “free ride.” Hermit crabs use the shells of dead snails for homes.

When two species benefit from each other, the symbiosis is called mutualism (or syntropy, or crossfeeding). For example, humans have a mutualistic relationship with the bacterium Bacteroides thetaiotetraiotamicron, which lives in the intestinal tract.

Mutualism describes the ecological interaction between two or more species where each species has a net benefit. The term mutualism was introduced by Pierre-Joseph van Beneden in his 1876 book Animal Parasites and Messmates to mean “mutual aid among species”.

mutualism—a symbiotic relationship where both organisms benefit.

Amensalism is the relationship between two organisms, where one is hurt. Amensalism is a biological interaction among two species. In this contact between two organisms, one is destroyed or inhibited, and other remains unaffected.

Relationships can be obligate, meaning that one or both of the symbionts entirely depend on each other for survival. For example, in lichens, which consist of fungal and photosynthetic symbionts, the fungal partners cannot live on their own.

Antibiosis is a widely recognized and effective biocontrol approach deployed by numerous PGPR for controlling the soil-borne infections in various crops (Handelman and Stabb, 1996).

: the suppression of growth of one plant species by another due to the release of toxic substances.

Common plants with allelopathic properties can be seen and include:

• English laurel (Prunus laurocerasus)
• Bearberry (Arctostaphylos uva-ursi)
• Sumac (Rhus)
• Rhododendron.
• Elderberry (Sambucus)
• Forsythia.
• Goldenrod (Solidago)
• Some types of fern.

Antibiosis is a biological interaction between two or more organisms that is detrimental to at least one of them; it can also be an antagonistic association between an organism and the metabolic substances produced by another.

Antibiotics, also known as antibacterials, are medications that destroy or slow down the growth of bacteria. They include a range of powerful drugs and are used to treat diseases caused by bacteria. Antibiotics cannot treat viral infections, such as cold, flu, and most coughs.

Unrelated organisms that occupy similar habitats and resemble each other. Ecological equivalents result from convergent evolution. For example, sharks (fish) and dolphins (mammals) live in a marine habitat and superficially resemble each other.

in math an equivalent refers to two sets. that have identical or corresponding. parts; in a similar way, ecological. equivalents are two species that occupy. identical niches but occur in different.

An organism’s niche is its role in the environment. Digestion is not part of an organism’s niche; it is part of the internal workings of the animal.