Answer: A Microtubules
Explanation: The cytoskeleton is composed of at last three different types of fibers: microtubules, microfilaments, and intermediate filaments. These fibers are distinguished by their size with microtubules being the thickest and microfilaments being the thinnest.
<span>rocks undergo this when stress builds up past a certain point, called the ... is any fracture or system of fracture or system of fractures along which earth ... the fracture is caused by horizontal shear and movement is mainly horizontal </span><span>many kind of rocks that make up Earth's crust fail when stress is applied too quickly ... The resulting fracture or system of fractures along which movement occurs.</span>
Transport proteins (carrier proteins and channel proteins) allow substances into and out of the cell that cannot pass through the phospholipid bilayer (as they’re either to large, charged or not lipid soluble) by facilitated diffusion.
Specifically channel proteins allow ions into and out of the cell by creating a pore in the membrane in which they can move through with their concentration gradient
The bones in a bird are hollow, reducing its weight for flight, this is an example of ADAPTATION. The adaptive responses emerge as a consequence of different environmental pressures.
<h3>Adapatation and environment</h3>
Adaptation is an evolutionary process by which organisms adjust to the environment in which they live.
For example, the bones in a bird are hollow because this adaptive feature enables them to fly.
Adaptations are a consequence of the process of natural selection, i.e., the differential survival and reproduction of the fittest organisms.
Learn more about adaptations here:
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