<span>R group (or side chain) is an organic component of amino acids that is unique to each amino acid. </span> <span>Three of the amino acids have basic side chains at neutral pH: arginine (Arg), lysine (Lys), and histidine (His). Their side chains contain nitrogen and resemble ammonia, which is a base and their pKa's are high enough that they tend to bind protons, (positive charge). Aspartic acid or aspartate (Asp) and glutamic acid or glutamate (Glu) are acidic amino acids because their side chains have carboxylic acid groups whose pKa's are low enough to lose protons, (negatively charged). The non-polar amino acids contain uncharged functional groups<span> at physiological pH and are incapable of participating in hydrogen bonding. </span></span>
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False
Pelagibacter ubique is often cited as the most<span> common organism ever, it's a third of all the single-celled organisms in the ocean.</span>
Answer and Explanation:
Observing population directly gives you accurate result .
Direct observation does not need any intermediary as they themselves go for survey.
So, it is cost efficient.
Whereas indirect observing may involve manipulations.
It requires someone or many to hire who helps in surveying.
It incurs cost.
Thus, direct observation is always better than indirect observation.
multiply the power of the eyepiece and objective lense Explanation:
No, there are unicellular organisms or single-celled organisms which have one cell...
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