BIO Test 4 Chapter 11b

Which statement most accurately explains how some signals are amplified?

Based on what you have learned about how cells ensure that proteins end up in the right place (Chapter 7), what type of signal would you expect to be exposed on a cytosolic receptor after a steroid hormone changes the receptor's conformation?

How do only certain cells respond to particular signaling molecules that may be sent throughout the body?

A cell with membrane-bound proteins that selectively bind a specific hormone is called that hormone's _____.

Different body cells can respond differently to the same peptide hormones because _____.

Which of the following is characteristic of a steroid hormone action?

The receptors for steroid hormones are located inside the cell instead of on the membrane surface like most other signal receptors. This is not a problem for steroids because _____.

Put the steps of the process of signal transduction in the order they occur: 1. A conformational change in the signalreceptor complex activates an enzyme. 2. Protein kinases are activated. 3. A signal molecule binds to a receptor. 4. Target proteins are phosphorylated. 5. Second messenger molecules are released.

Protein kinase is an enzyme that _____.

Steroid hormones bind to receptors inside the cell and alter their conformation. The hormonereceptor complex is then transported into the nucleus, where it can directly affect gene expression. To get from the location where the receptor binds the hormone to its site of action, the hormonereceptor complex must ________.

Not all intercellular signals require transduction. Which one of the following signals would be processed without transduction?

Acetylcholine is a neurotransmitter that binds to receptors on skeletal muscle cells. The receptorsignal complex brings about a series of events that result in contraction of skeletal muscle. Venom from black widow spiders causes an explosive release of acetylcholine. What would that do to its victims?

One of the major categories of receptors in the plasma membrane reacts by forming dimers, adding phosphate groups, and then activating relay proteins. Which type does this?

In general, a signal transmitted via phosphorylation of a series of proteins _____.

At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many effects?

Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because they _____.

The activation of receptor tyrosine kinases is characterized by _____.

Consider this pathway: epinephrine → G-protein-coupled receptor → G-protein → adenylyl cyclase → cAMP. The second messenger in this pathway is ________.

How can a hormone that is present in very small quantities within the bloodstream elicit such a large response within a cell?

How is phosphorylation important in a signal transduction cascade?

Why is it important for signal transduction systems to trigger a rapid response within a cell and be able to be shut down quickly?

A bacterium lacking the receptor for responding to quorum-sensing signals would be unable to ________.

The cleavage of glycogen by glycogen phosphorylase releases _____.

A toxin that inhibits the production of GTP would interfere with the function of a signal transduction pathway that is initiated by the binding of a signal molecule to _____ receptors.

A signal transduction pathway is initiated when a _____ binds to a receptor.

A signal molecule is also known as a(n) _____.

Which of these is the second of the three stages of cell signaling?