When two protein chains combine to form an active protein, the structural level is quaternary.
<h3>What is a quaternary structure?</h3>
The quaternary and tertiary structure of a protein is the tridimensional shape of the protein, which involves protein domains.
The quaternary protein structure refers to the different arrangements generated by different protein subunits.
The primary structure of a protein involves its amino acid sequence, whereas the second structure involves protein chains.
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Friction always opposes motion.
<span>Whether it be through air resistance, or simple surface friction, the speed of a moving body always decreases when some frictional force acts on it. For objects sliding on a surface, friction is less than for objects at rest on the same surface
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A group of cells that performs a similar function is known as tissue.
