A lichen is an organism that results from a mutualistic relationship between a fungus and a photosynthetic organism. The other organism is usually a cyanobacterium or green alga. The fungus grows around the bacterial or algal cells.
Answer:
Option B, Mammals and reptiles in the post-dinosaur age.
Explanation:
Adaptive radiation is mechanism through which species evolve very fast from common single ancestors. In simple words two different species are said to have evolved through adaptive radiation when they have descended from a single lineage. This is not the case with mammals and reptiles.
Generally in adaptive radiation, a species evolve when it faces new environmental challenges due to change of habitat or area. For example mammals have evolved from dinosaurs.
Hence, option B is correct
Answer:
It would contain four electrons.
Explanation:
A neutral atom has equal numbers of protons and electrons. Therefore, a neutral atom with four protons will also have four electrons.
FYI an atom with four protons is an atom of the element beryllium, Be.