Answer & explanation:
Primary succession occurs in environments that did not have biological communities in place and present unfavorable conditions for the establishment of life. Examples of these sites are rocks, dunes and newly solidified lava pits.
The pioneer organisms in primary succession are mainly producers and some decomposers.
In <u>dune</u> <u>environments</u>, for example, there are grasses, whose seeds are wind-borne and able to withstand excessive heat, water scarcity and unstable soil, and their roots are firm, preventing these plants from being harmed by the wind.
Sites with <u>rocky</u> <u>surfaces</u> can be colonized by photosynthetic bacteria, fungi or some species of algae. These organisms release substances that alter the substrate, allowing the installation of new species over time.
Answer:
a.they work together to allow gas exchange
Explanation:
the trachea helps transport air to the lungs, the lungs fill with air, finally the alveoli convert the oxygen to the bloodstream
I believe the answer would be C.
They are classified base on the viral surface proteins.
The fourth option is right one....lymph vessels drain extra water from tissues !!
It's Adenine so the answer is C.
