Multiple Choice
The molecules that convert extracellular signals into intracellular signals are:
a) Neurotransmitters.
b) Hormones.
c) Cell surface receptors.
d) Intracellular receptors.
10. Cell Signaling
Classes of Signaling Receptors
Back10. Cell Signaling
Classes of Signaling Receptors
- Multiple Choice
Which type of receptor leads directly to a change in the distribution of ions on opposite sides of the membrane?
a) Receptor tyrosine kinase.
b) G protein-coupled receptor.
c) Ligand-gated ion channel.
d) Steroid receptor.
e) Intracellular receptor.
- Multiple Choice
Why does testosterone, a lipid-soluble / hydrophobic signaling molecule, not affect all cells in the body but only specific cells?
a) Only target cells have the cell surface receptor able to bind with testosterone.
b) Only target cells contain the genes regulated by testosterone.
c) Only target cells possess the phosphorylation cascade uniquely activated by testosterone.
d) Only target cells possess the intracellular receptor able to bind with testosterone.
- Multiple ChoiceReceptors for signal molecules __________.
- Multiple ChoiceTestosterone and estrogen are lipid-soluble signal molecules that cross the plasma membrane by simple diffusion. If these molecules can enter all cells, why do only specific cells respond to their presence?
- Multiple ChoiceSteroid hormones can enter a cell by simple diffusion. Therefore, steroids __________.
- Multiple ChoiceTestosterone does not affect all cells of the body because __________.
- Multiple ChoiceG-protein-coupled receptors __________, whereas receptor tyrosine kinases __________.
- Multiple ChoiceWhich of the following is activated when the binding of single molecules causes it to form a dimer?
- Multiple ChoiceDomoic acid is a neurotoxin produced by some species of alga. Domoic acid binds to the kainate receptor on neurons in parts of the brain. The kainate receptor facilitates the movement of calcium into the cell. Excess domoic acid–induced stimulation of the neural kainate receptors causes neural damage and short-term memory loss. Based on this, which of the following is likely true?
- Multiple ChoiceA G protein is active when __________.
- Multiple ChoiceIf a modified form of GTP that cannot be enzymatically converted to GDP were added to a culture of cells, the likely result would be __________.
- Multiple ChoiceWhat event would activate a G protein?
- Multiple ChoiceRas, a small G protein located at the plasma membrane, is often mutated in different types of cancer. Ras normally signals to a cell that it should divide. Cancer cells divide uncontrollably. Which of the following changes to Ras could explain uncontrolled division in a cancer cell that has mutated Ras present?
- Multiple ChoiceCholera develops when the bacterial toxin __________.