Questions and Answers
Which of these is a receptor molecule?
A signal transduction pathway is initiated when a _____ binds to a receptor.
signal molecule
Which of these is a signal molecule?
A signal molecule is also known as a(n) _____
Signup and view all the answers
Which of these is the second of the three stages of cell signaling?
Signup and view all the answers
What are the three stages involved in the process of a signal converting to a specific cellular response?
Signup and view all the answers
Describe the interaction of cortisol with intracellular receptors.
Signup and view all the answers
Which of the following are plasma membrane receptors?
Signup and view all the answers
What do G protein-coupled receptors do?
Signup and view all the answers
What do receptor tyrosine kinases do?
Signup and view all the answers
G protein-coupled receptors and receptor tyrosine kinases both have their binding sites for signaling molecules on the intracellular side of the cell.
Signup and view all the answers
Which statements are true about the binding of histamine to the histamine H1 receptor?
Signup and view all the answers
Which of these acts as a second messenger?
Signup and view all the answers
Calcium ions that act as second messengers are stored in _____.
Signup and view all the answers
_____ catalyzes the production of _____, which then opens an ion channel that releases _____ into the cell's cytoplasm.
Signup and view all the answers
What is amplification in cell signaling?
Signup and view all the answers
Which of the following lists represents the stages of signal transduction?
Signup and view all the answers
Which of the following could account for the different cellular responses to histamine?
Signup and view all the answers
What is apoptosis?
Signup and view all the answers
Study Notes
Receptor Molecules and Signal Transduction
- Receptor molecules are essential for cell signaling, with examples including G protein-coupled receptors and receptor tyrosine kinases.
- A signal transduction pathway is triggered by a signal molecule (ligand) binding to a receptor, leading to a series of cellular responses.
Stages of Cell Signaling
- The process encompasses three stages:
- Reception: signaling molecule binds to receptor.
- Transduction: signal converted to a cellular response.
- Response: triggered cellular activities, often involving gene expression.
Hormonal Interaction
- Cortisol, a steroid hormone, passes through the plasma membrane, binds to intracellular receptors, forms a complex, and enters the nucleus to influence gene transcription.
Types of Receptors
-
Plasma Membrane Receptors include:
- G protein-coupled receptors, which interact with G proteins.
- Receptor tyrosine kinases, which form dimers and transfer phosphate groups to the receptor itself.
Mechanisms of Action
- G protein-coupled receptors and receptor tyrosine kinases manage signaling on the extracellular side and are located within the plasma membrane.
- Histamine binding to H1 receptors initiates a conformational change that activates G proteins, which then interact with phospholipase C.
Second Messengers and Amplification
- Examples of second messengers include cyclic AMP and calcium ions, which facilitate downstream signaling.
- Amplification occurs when a single activated protein kinase cascades to activate multiple other kinases.
Cellular Responses and Variability
- Different responses to histamine arise due to varying second messengers, enzymes activated by G proteins, relay molecules, and cell types expressing histamine receptors.
Apoptosis
- Apoptosis refers to controlled cell suicide, a crucial process for maintaining cellular health and development.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the intricate mechanisms of cell signaling, including receptor molecules like G protein-coupled receptors and receptor tyrosine kinases. Understand the stages of signal transduction and the effects of hormones like cortisol on cellular responses.
