Cortisol is a steroid hormone that can pass through the plasma membrane. Complete the flowchart describing the interaction of cortisol with intracellular receptors.

Cortisol binds to a receptor on the outside of the cell.

Cortisol-receptor complex forms in the nucleus.

Cortisol passes through the plasma membrane into the cytoplasm.

Cortisol-receptor complex forms in the cytoplasm.

Cortisol-receptor complex enters the nucleus where it binds to genes.

The Cortisol-receptor complex acts as a transcription factor.

The transcribed mRNA is translated into a specific protein.

1.) Cortisol passes through the plasma membrane into the cytoplasm.

2.) Cortisol-receptor complex forms in the cytoplasm.

3.) Cortisol-receptor complex enters the nucleus where it binds to genes.

4.) The Cortisol-receptor complex acts as a transcription factor.

5.) The transcribed mRNA is translated into a specific protein

Unlike steroid hormones, signaling molecules that are large and/or hydrophilic cannot pass through the cell’s plasma membrane and therefore must bind extracellularly to receptor molecules in the plasma membrane. Two types of signal receptors embedded in the cell's plasma membrane are G protein-coupled receptors and receptor tyrosine kinases. Classify each phrase by whether it applies to G protein-coupled receptors only, receptor tyrosine kinases only, both receptors, or neither receptor.

interact directly with G proteins

catalyzes the transfer
of a phosphate group
to the receptor

binding of the signaling
the molecule forms a dimer

binding site for signaling
molecule is located on the
extracellular side of the cell

receptor is located in the
plasma membrane

binding of the signaling molecule
allows ions to flow through a
channel in the receptor

G-protein Coupled Receptor: interact directly with G proteins

Receptor Tyrosine Kinases: catalyzes the transfer
of a phosphate group to the receptor, binding of the signaling
the molecule forms a dimer

Both types of receptors: binding site for signaling
molecule is located on the extracellular side of the cell, receptor is located in the plasma membrane

Neither Receptor: binding of the signaling molecule
allows ions to flow through a
channel in the receptor

Histamine is a chemical substance released in inflammatory and allergic responses. The histamine H₁ receptor on target cells is a G protein-coupled receptor that activates phospholipase C in response to the binding of histamine.

Histamine diffuses across the plasma membrane to bind to the H₁ receptor.Histamine binds extracellularly to the H₁ receptor.

When histamine binds to the H₁ receptor, the receptor undergoes a conformation change and binds the inactive G protein.

Histamine binds intracellularly to the inactive G protein, activating the G protein

.Once the G protein is active, it binds to the enzyme phospholipase C, activating it.

Histamine is likely hydrophilic.

Histamine binds extracellularly to the H₁ receptor.

When histamine binds to the H₁ receptor, the receptor undergoes a conformation change and binds the inactive G protein.

Once the G protein is active, it binds to the enzyme phospholipase C, activating it.

Histamine is likely hydrophilic.

Cell signaling involves converting extracellular signals to specific responses inside the target cell. Different molecules are involved at each stage of the process. In this activity, you will sort items based on which stage they are involved in: reception, transduction, or response.

• • signaling molecule
  • G protein-coupled receptor
  • receptor tyrosine kinase
  • adenylyl cyclase
  • cAMP
  • IP3IP3
  • phosphorylation cascade
  • Ca2+Ca2+
  • second messenger
  • protein synthesis

Reception:

• signaling molecule
• G protein-coupled receptor
• receptor tyrosine kinase

Transduction:

• adenylyl cyclase
• cAMP
• IP3IP3
• phosphorylation cascade
• Ca2+Ca2+
• second messenger

Response:

• protein synthesis