Cell
Tissue
Organ
Organ System
Organism
Explanation:
the most common gas in the atmosphere is nitrogen and oxygen followed by CO2 etc...
The antibiotic called ampicillin was not effective against E.coli.
Answer: D
Explanation:
E.coli is normal microbial flora which is present in the gut of the mammals.
It is gram negative bacteria and very few strains of this bacteria causes harm.
Antibiotics are the chemical drugs which are used to treat the microbial infection either by killing the causative organism or by its growth inhibition.
Antibiotics such as neomycin, penicillin and erythromycin are usually used to treat E.coli infection.
Antibiotic such as Ampicillin is not used as the bacterium E.coli is highly resistant to it.
I believe the correct answer is A) Silurian period occurred before the Neogene era, because the other answer are wrong.
Hadean eon ended before Silurian period.
Mesozoic and Permian era were after Silurian period.
Carbon Dioxide is the main cause, but other effectors include nitrous oxide and <span>methane.
Hope this helps!</span>