<span>Centrosomes are made of from arrangement of two barrel-shaped clusters of microtubules, called “centrioles,” and a complex of proteins that help additional microtubules to form.</span>
Answer: B. Osmosis Across a Membrane
The movement of water across a gradient is called osmosis.
The way that you will easily deduce which one it is is that you'll see the mouth first instead of the anus because of the different ways of development.
During an emergency what you would usually want to do is a so-called threat and hazard analysis - C.
You would do this because you would want to observe and note which is a source of threat for you in a certain emergency situation. You would also to this to observe the possible hazards of doing a certain action/certain actions.
I think the correct answer is nucleic acid. There four major classes of macromolecules and these are lipids, carbohydrates, proteins and nucleic acids. Among these nucleic acid would best fit the definition. Examples of nucleic acids are DNA and RNA.
