Seeds and vegetables are often deficient in one or more essential amino acids. Using the following table, state whether each combination provides all of the essential amino acids:

b. lima beans and cornmeal

What is meant by the following terms as they apply to protein structure, and what bonds or molecular interactions stabilize that level of structure?

a. Primary structure

Do the following peptides have an identical primary structure?

Explain why each of the following pairs are complementary proteins:

a. beans and oats

Draw the condensed structural formula for Ser–Lys–Asp.

Seeds and vegetables are often deficient in one or more essential amino acids. Using the table in problem 16.63, state whether each combination provides all of the essential amino acids.

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a. rice and lima beans

Seeds and vegetables are often deficient in one or more essential amino acids. Using the table in problem 16.63, state whether each combination provides all of the essential amino acids.

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c. oatmeal and lima beans

How many different tripeptides that contain one leucine, one glutamate, and one tryptophan are possible?

The endorphins are a group of naturally occurring neurotransmitters that act in a manner similar to morphine to control pain. Research has shown that the biologically active parts of the endorphin molecules are simple pentapeptides called enkephalins. Draw the structure of the methionine enkephalin with the sequence Tyr-Gly-Gly-Phe-Met. Identify the N-terminal and C-terminal amino acids.