Answer: The question is not complete as options are not complete , the remain part are;
A. 3.7 years, photosynthetic bacteria.
B. 3.7 years cyanobacteria.
The correct option is
3.7 billion years old, cyanobacteria and stromatolite.
Explanation:
This is because cyanobacteria is the oldest fossil to exist and they have been in existence for about 3. 7 billion years. These cyanobacteria photosynthesized because they have thread like chlorophyll filament, they produce food through the process of photosynthesis which is needed for their survival and they release oxygen as bye product.
Answer:
Pons.
Explanation:
Inside of our brainstem, there is a structure which is called the pons, which is present besides the medulla oblongata. The pons is a significant structure in the upper part of our brainstem. It controls breathing, communication between different parts of the brain, and as well as sensations such as hearing, taste, and balance.
Pons is that part of the brainstem which carries one-way communications that advise the cerebellum of voluntary motor activities initiated by the motor cortex.
Answer:
Mid-Atlantic Ridge
Explanation:
This is because they are deep down, near the earth's crust .
Keystone species, they kinda hold the food webs together
