Answer:
<em>B. Nucleic acid
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Explanation:
DNA and RNA
Fluorite can scratch a copper coin but cannot be scratched by a copper coin.
This is because according to Mohs scale of hardness, fluorite has a hardness of four. Copper has a hardness of three. Therefore fluorite is a harder mineral than copper and will scratch copper but it will not be scratched by copper.
Mohs based his scale on the fact that some minerals could scratch others. If one mineral could scratch another but could not be scratched by it, he reasoned that it must be harder.
Answer: lens; retina
In myopia<span>, close objects look clear but distant objects appear blurred. Hyperopia is the reverse of myopia. Here you can see distant objects clearly, but have difficulty focusing on objects that are near. People have myopia (nearsightedness) and hyperopia )farsightedness) because the distance between their lens and their retina is either too short or too long.</span>
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Answer:
Fibrous
Explanation:
Proteins are assembled according to their functions. Fibrous proteins usually provide protection and support to cells. They are made up of polypeptides that have elongated shape and assembles in large cables or threads. These proteins are differentiated from globular proteins by their globular form and repeated units of amino acids.
For example the fibrous proteins involved in horns, hair and nails is alpha-keratin. Elastin found in skin and ligament is also a fibrous protein. Collagen includes collagen fibrils that have tensile strength of steel is also a fibrous protein found in cartilages and bones.
