Answer:
C.were formed at the same time.
Explanation:
If the same index fossils occurred in two separate rock layers, the two rock layers would probably have been established at the same time. Index fossils aid the characterizing and classify of geologic period.
The correct answer is cyanobacteria (ancient cyanobacteria).
The huge concentration of oxygen in the atmosphere is believed to have been initially produced by the actions of ancient cyanobacteria. They are usually observed as symbionts with a number of another group of species, like coral, lichens (fungi), Azolla (pteridophytes), angiosperms, and others.
The atmosphere of oxygen was generated by various cyanobacteria at the time of Proterozoic and Archaean periods.
Answer:
B.) Gap junction
Explanation:
Plasmodesmata (singular form: plasmodesma) are intercellular organelles found only in plant and algal cells. (The animal cell "equivalent" is called the gap junction.)
Answer:
B) Autotrophes
Explanation:
Producers are <u>autotrophes</u> because, they make their own food. Hence, the option (b) is the correct answer.
