Cell Signaling Mechanisms and Functions

What is a receptor in cell communication?

• A molecule that transmits signals to other cells.

• A molecule, often a protein, that a signal molecule binds to.

• A type of cell that sends messages.

• A small molecule that carries a message.

What is the correct order of the three general steps in cell signaling?

• Transduction, Reception, Response

• Response, Transduction, Reception

• Reception, Transduction, Response

• Reception, Response, Transduction

How do animal cells communicate through direct contact?

• By releasing hormones into the bloodstream.

• Through gap junctions that allow small molecules to pass.

• By secreting molecules that bind to their own receptors.

• Using neurotransmitters across a synapse.

Which type of cell signaling involves signal molecules traveling through the bloodstream to reach distant target cells?

• Paracrine signaling

• Synaptic signaling

• Autocrine signaling

• Endocrine signaling

What is the first step a steroid hormone takes after entering a cell to initiate a cellular response?

• It directly binds to the cell's DNA in the nucleus.

• It immediately triggers the production of new proteins.

• It binds to a protein receptor located inside the cell.

• It changes the structure of the cell's outer membrane.

Why would a cell use a surface receptor for a ligand instead of allowing the ligand to enter the cell directly?

• The ligand is too large to fit through the cell membrane.

• The ligand is hydrophilic, making it difficult to pass through the membrane.

• The cell needs to quickly destroy the ligand after it binds.

• The ligand is a steroid hormone that needs to reach the nucleus.

How does a ligand-gated ion channel allow ions to enter a cell?

• The ligand passes through the channel, pulling ions with it.

• The ligand binds to the channel, causing the channel to open for ions.

• Ions are able to float directly through the cell membrane without assistance.

• The channel actively pumps ions into the cell without needing a ligand.

Which of the following describes how a problem with cell signaling can lead to cancer?

• Cancer cells stop responding to all growth signals.

• Cancer cells produce too much of their own growth factor, leading to uncontrolled division.

• Cancer cells develop stronger connections with neighboring healthy cells.

• Cancer cells lose the ability to divide and grow.