document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1091943>Question 1091943</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An octapeptide is known to contain four of one amino acid, two of another and two of third. How many different amino acid sequence are possible? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #706442 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=706442\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "An octapeptide is known to contain four of one amino acid, two of another and two of third. How many different amino acid sequence are possible?<BR>\n" );
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document.write( "To correctly answer this question, we need to know what sequences (what connections and interconnections) are allowed.\r<BR>\n" );
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document.write( "If ALL sequences and connections are allowed in one-line-arrangement, then the following logic works:\r<BR>\n" );
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document.write( "    In total, there are 4 + 2 + 2 = 8 amino acid (acids ?).\r\n" );
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document.write( "    Anyone of 8 acids           can be placed in the 1-st position.\r\n" );
document.write( "    Anyone of remained 7 acids can be placed in the 2-nd position.\r\n" );
document.write( "    Anyone of remained 6 acids can be placed in the 3-rd position.\r\n" );
document.write( "    Anyone of remained 5 acids can be placed in the 4-th position.\r\n" );
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document.write( "    . . . .   and so on  . . . . \r\n" );
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document.write( "    Anyone of remaining 2 acids can be placed in the 7-th position.   \r\n" );
document.write( "    And    there is no choice (except the remained 1 last acid) in the 8-th position.\r\n" );
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document.write( "    If this logic is correct from the Chemistry/Biochemistry point of view,\r\n" );
document.write( "    then the answer is  8*7*6*5*4*3*2*1 = 40320 different amino acid sequences are possible.\r\n" );
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document.write( "I am not a Chemist in my education, so my logic easily can be wrong.\r<BR>\n" );
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document.write( "It is your responsibility to evaluate if it is True or False.\r<BR>\n" );
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document.write( "If it not difficult to you, I would appreciate your feedback, which you can send me through the \"Thank you\" note.\r<BR>\n" );
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document.write( "In this case, please refer to the Problem ID number, which is 1091943.\r<BR>\n" );
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document.write( "Thank you and good luck !!\r<BR>\n" );
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document.write( "From Wikipedia,  https://en.wikipedia.org/wiki/Peptide\r<BR>\n" );
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document.write( "    An octapeptide has eight amino acids (e.g., angiotensin II).\r\n" );
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document.write( "From Wikipedia,  https://en.wikipedia.org/wiki/Angiotensin#Angiotensin_II\r<BR>\n" );
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document.write( "    Angiotensin II\r\n" );
document.write( "    Asp-Arg-Val-Tyr-Ile-His-Pro-Phe | His-Leu\r\n" );
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document.write( " </SPAN>\n" );
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