Many insects have a tough outer shell called an exoskeleton..
UUAGCU in mRNA U-T and C-G
The correct answer is a - silicon dioxide.
Diatoms are single celled algae. They have a silica - based cell wall called a frustule, which gives each diatom a particular shape.
Diatoms exist as separate single cells although some may be found in groups or colonies. The ones found in colonies create very pretty forms: leaf shaped, oval , star and even like a period.
Outer shells of diatoms are quite valuable. They are used in industry in the manufacture of toothpaste to give it grit.
When the continents separated, organisms were forced to be placed in different locations with different environmental conditions. In order to survive in their new environment, over time, various flora and fauna developed various body mechanisms to cope up. This brought up the speciation of flora and fauna.
3) 2 monoploid cells (also known as haploid)