Answer:
a. commensalism is the correct answer.
Explanation:
By growing on the trunk or branch of a tree, a lichen gains height and exposure to sunlight for photosynthesis. The tree is not harmed by the lichen but does not benefit either. The relationship between the lichen and the tree is commensalism.
Commensalism is a relationship between two organisms where one organism gets benefits from other organisms without causing any harm or any damage from the relation as it one side symbiotic relation.
In this, we can see lichen is getting benefits from the tree.
for example, lichen is getting following benefits from the tree such as ( a lichen gains height and exposure to sunlight for photosynthesis.) and they are causing any harm to tree neither any benefits so this is a one-side symbiotic relation and thus the relationship is an example of commensalism.
Answer: covering crops
Explanation:
such as vetch, rye and clover, are excellent plants for erosion control. These hardy easy to grow plants send out nets of roots that help hold topsoil in place while also reducing competitive weeds. When tilled back into the soil, they increase the nutrient density as they compost.
The concentration of the substance is greater outside the cell than inside.
