E Coli bacterium are about 2.0 micrometers in length and .25 to 1 micrometer in diameter. In comparison, a red blood cell is about 6 to 8 micrometers in diameter and a thickness that ranges from .8 to 1 micrometer in the center to 2 to 2.5 micrometers at the thickest point.
Answer:
have curved protofilaments at their plus ends
Explanation:
Microtubules are polymers of tubulin proteins that function as the cytoskeleton of eukaryotic cells. Microtubules are dynamic structures that can grow and shrink at a rapid rate. During this process, tubulin subunits can associate and dissociate at the plus end of the protofilament. Tubulin subunits bind to two GTP molecules, one of which is hydrolyzed to GDP after assembly. When microtubules are unstable, protofilaments curl outwards because GDP-bound tubulin has a weak affinity (thereby curving it) and disassemble. The dynamic stability of microtubules is regulated by a feedback loop: when microtubules shrink, free tubulin concentration increases and microtubules start to grow. As microtubules grow, free tubulin concentration decreases and the rate of GTP-tubulin addition also decreases.
Plants and animals provide food for humans. Plants cycle the air for humans too.
Answer:
C. They are made from many carbon atoms
Explanation:
Water and ice and i dont know the rest