Exam 11: Cell Communication

Caffeine is an inhibitor of phosphodiesterase. Therefore, the cells of a person who has recently consumed coffee would have increased levels of which of the following molecules?

If an adult person has a faulty version of the human analogue to ced-4 of the nematode, which of the following is most likely to result?

Cells that are infected, damaged, or have reached the end of their functional life span often undergo "programmed cell death". This controlled cell suicide is called "apoptosis". Select the appropriate description of this event on a cell's life cycle.

Sutherland discovered that the signalling molecule adrenaline is responsible for which of the following events?

Which observation suggested to Sutherland the involvement of a second messenger in adrenalineadrenaline's effect on liver cells?

If a pharmaceutical company wished to design a drug to maintain low blood sugar levels, one approach might be to design a compound that does which of the following?

When a neuron responds to a particular neurotransmitter by opening gated ion channels, the neurotransmitter is serving as which part of the signal pathway?

What role do phosphatases play in signal transduction pathways?

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

Viagra causes dilation of blood vessels and increased blood flow to the penis, facilitating erection. Viagra acts by inhibiting which of the following events?

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

- Which of the following types of signalling is represented in the figure?

Binding of a signalling molecule to which type of receptor leads directly to a change in the distribution of ions on opposite sides of the membrane?

Why has C. elegans proven to be a useful model for understanding apoptosis?

A mutation that knocks out the GTPase activity of a G protein would have what effect on a cell?

Which of the following is true during a typical cAMP-mediated signal transduction event?

In the nematode C. elegans, ced-9 prevents apoptosis in a normal cell in which of the following ways?

Which of the following provides the best evidence that cell-signalling pathways evolved early in the history of life?

Protein kinase is an enzyme that functions in which of the following ways?

If an animal cell suddenly lost the ability to produce GTP, what might happen to its signalling system?