Although the Expression of Most Genes Is Tightly Regulated, Some

question 38

Multiple Choice

Although the expression of most genes is tightly regulated, some genes are expressed at roughly constant rates i.e., constitutively) . Which of the following genes would you predict to be constitutively expressed?

• A) genes involved in the biosynthesis of the amino acid tryptophan
• B) genes involved in the transport of the sugar maltose
• C) genes that code for ribosomal RNAs
• D) genes involved in the degradation of arabinose, a sugar
• E) genes involved in the degradation of tryptophan

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Definitions:

Skeletal Muscle

A type of muscle that is connected to bones and is responsible for voluntary movements of the body.

Sensory Neurons

Nerve cells that transmit sensory information (e.g., touch, sound, visual) from the body to the central nervous system for interpretation.

Axon

A long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses away from the neuron's cell body.

Sarcomere

The basic contractile unit of muscle fiber, consisting of actin and myosin filaments, responsible for muscle contraction.