B ecosystem because it affect a lot of thing ,especially you phenotype
Answer:
Microtubules composed of tubulin protein.
Explanation:
The cytoskeleton is composed of three well defined filamentous structures: microtubules, microfilaments, and intermediate filaments. Each of these filamentous structures is a polymer of proteinic subunits united by weak, not covalent connections.
Microtubules are long hollo cylindric tubes with no ramifications of a diametre near to 25 nanometers. They are constituted by two subunits of tubulin protein which polymerize to form microtubules. These filaments shape the cell and are involved in intracellular transport. Microtubules extend from an organizing center near the nucleus to the cellular surface.
Answer:
a model from which later versions are developed
Explanation:
prototype is the first or preliminary version of something