These threadlike structures that form muscle fibers are called myofibrils.
They are very long fibers organized into myofilaments, that layer on top of each other to create myofibrils, which then layer in order to create muscle fibers, which then layer to create muscles, which they cover our entire body and make up the muscular system of organisms.
Answer:
but no the answer is spine which can also be called vertebral column so is B
It is a direct result of Respiration
Answer:
Although all of the options are important but the best reason is
a) Nitrogen is an essential part of biological molecules such as proteins and nucleic acids (DNA).
Explanation:
- Nitrogen is an essential component of building blocks of life that are DNA, RNA and Protein. It is also needed for the production of chlorophyll. We can say there would be no life without nitrogen.
- Air we breathe is 78% nitrogen but that is in inert form (N2) and we can't use it.
- Nitrogen cycle is the process by which nitrogen circulates into various forms of nature and it make the nitrogen useful to carryout life.
