Answer:
The diatom cells are not interconnected and are very similar to diatoms that are living unicellularly. The Spirogyra cells are the building blocks of the filaments.
Explanation:
Because any other substance couldn't carry the heat and the amount of surface area gives it more of an opportunity to cool down
Answer:
25nm
Explanation:
Microtubules are polymers of tubulin and they are part of the cytoskeleton. The roles of the microtubules are to maintain the shape and structure of the cell, intracellular transport, they are structural part of the cilia an flagella, they are involved in cell division etc.
Tubulin that is the basic unit of microtubules is composed of two globular proteins, alpha and beta tubulin. Alpha and beta subunits spontaneously form dimers which then assemble into oligomers, then in chains (protofilaments); that can form a variety of intermediate structures such as single and double rings or spirals. Protofilaments that associate side-by-side form sheets of protofilaments which then curle to form a tube or cylinder (closing of microtubule). Continued growth of microtubules occurs by the direct addition of more dimers on + side.