Cell Signaling Quiz

What directs the activities of individual cells within a multicellular organism?

• Signal molecules released by controlling cells

• Nutrients absorbed by the cells

• Waste products expelled by the cells

• Water molecules within the cells

What do target cells have that recognize signal molecules?

• Receptors

• Enzymes

• Mitochondria

• Nuclei

How many signal molecules can a target cell recognize?

• Only one or a few

• All signal molecules

• None

• Hundreds

What triggers a signaling pathway that results in a response in the target cell?

• A signal molecule

• A protein

• A carbohydrate

• A lipid

Which of the following is NOT a response that may be included in cell signaling?

• Changes in gene activity

• Protein synthesis

• Transport of molecules across the plasma membrane

• Formation of new cells

What are the three sequential steps in which target cells process the signal?

• Reception, Transduction, Response

• Reception, Translation, Response

• Reception, Transcription, Response

• Reception, Transformation, Response

What is quorum sensing in bacteria?

• Bacteria release signal molecules in increasing concentration as cell density increases.

• Bacteria release signal molecules in decreasing concentration as cell density increases.

• Bacteria release signal molecules in constant concentration regardless of cell density.

• Bacteria do not release signal molecules.

When did other proteins in the pathways, such as protein kinases, appear?

• Before prokaryotes evolved

• Only after eukaryotes evolved

• At the same time as prokaryotes

• Before eukaryotes evolved

One pathway for cell growth control is conserved between which two organisms?

• Bacteria and humans

• Plants and animals

• Fruit fly (Drosophila) and humans

• Yeast and humans

How old is the pathway for cell growth control that is conserved between the fruit fly and humans?

• 500 million years old

• 600 million years old

• 700 million years old

• 800 million years old