Corse Q-1

What is a receptor typically composed of?

• Lipid

• Carbohydrate

• Protein

• Nucleic acid

What is a substrate in the context of enzyme activity?

• A molecule that binds to a receptor

• A molecule that binds to the active site of an enzyme

• A molecule that acts as a second messenger

• A hormone or neurotransmitter

What is a ligand?

• A molecule that binds irreversibly to a receptor

• A molecule that binds reversibly to a receptor

• A molecule that acts as a first messenger

• A molecule that is a substrate for an enzyme

What does specificity refer to in the context of receptors?

• The ability of a receptor to bind to any molecule

• The fact that only a specific type and shape of molecule can fit into a binding site on the receptor

• The irreversible binding of a ligand to a receptor

• The creation of a second messenger

What is a first messenger?

• A molecule created following receptor binding

• A hormone or neurotransmitter

• A molecule that binds to the active site of an enzyme

• A molecule that acts as a second messenger

What is a second messenger?

• A molecule that binds to a receptor

• A molecule that binds to the active site of an enzyme

• A molecule created following the binding of the first messenger to its receptor, e.g., cAMP, cGMP, IP3, Ca++

• A hormone or neurotransmitter

What is signal transduction?

• The process of a ligand binding to a receptor

• The specific cellular effects that result from receptor binding

• The creation of a second messenger

• The binding of a substrate to an enzyme

What is endocrine signaling?

• Hormone binding at a local site

• Hormone binding at a distance site

• The release of neurotransmitters

• The creation of a second messenger

Which of the following is an example of a second messenger?

• ATP

• cAMP

• Glucose

• DNA

What type of molecule is typically involved in paracrine signaling?

• Hormones

• Neurotransmitters

• Enzymes

• Lipids