a. in a structural sense (membranes, connective tissue)
b. for transport mechanisms (hemoglobin)
c. for maintenance of fluid balance (blood serum albumin)
d. for regulation of metabolism (hormones)
e. in genetics (nucleoproteins)
f. in defense mechanisms (blood gamma-globulins)
g. enzymes for catalyzing biologically important chemical reactions.

1. ACTH is a relatively small protein with only 39 amino acid groups linked by peptide bonds. It is single chained. Thus it is relatively easy to draw.

2. This assignment is probably a highly stressful one as is your entire experience with high school chemistry. And yet, ACTH is a pituitary hormone which the body releases exactly in response to the environmental stress that this assignment is designed to produce. Thus, while you are constructing external models of ACTH, you will likely be experiencing internal feelings that stem directly from your own secretion of this corticosteroid. You will also secrete ACTH in response to other, less disagreeable problems such as infectious diseases and traumatic shock, to name but two.

The amino acid sequence in ACTH is:
Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val-
Gly-Lys-Lys-Arg-Arg-Pro-Val-Lys-Val-Tyr-Pro-Ala-Gly-
Glu-Asp-Asp-Glu-Ala-Ser-Glu-Ala-Phe-Pro-Leu-Glu-Phe

The amino acid, tyrosine, which appears in the chart as:

Should be written

or