Position-Specific Weight Matrix Tables Show Relatively Few Substitutions for Cysteine

question 25

Multiple Choice

Position-specific weight matrix tables show relatively few substitutions for cysteine and tryptophan compared with other proteins. Which of the following are possible explanations for this? Please select all that apply.

• A) Cysteine and tryptophan are more likely to have essential roles in the mature protein than other amino acids
• B) Cysteine and tryptophan are larger than other amino acids.
• C) Cysteine and tryptophan have unusual structures
• D) The codons for cysteine and tryptophan are similar to a stop codon

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Definitions:

Reflexive Response

An automatic, involuntary reaction to a stimulus that does not involve conscious thought.

Conditioned Response

A learned response to a previously neutral stimulus that has been repeatedly presented along with an unconditioned stimulus.

Stimulus

Any event or situation that evokes a response from an organism or system.

Extrinsic Rewards

Benefits and incentives provided from an external source, used to motivate behavior that might not occur otherwise.