Exam 7: Cell Communication and Multicellularity

A key event in the rise of multicellularity is the ability of cells to _______ with one another, as has been observed in some types of algae that live in multicellular clusters.

A pharmaceutical chemist synthesizes a compound that differs chemically from the molecule that binds to a specific three-dimensional site on a cellular receptor.The synthesized compound is a(n) _______ if it elicits the same biological response as its biologically active counterpart.

Refer to the figure below. Which equation describes the rate of binding of a ligand to its receptor? In all equations shown, "R" represents a receptor with no ligand bound, "L" represents a free ligand in solution, and "RL" represents a receptor bound to a ligand.

The figure below shows the oxytocin signal transduction pathway in uterine smooth muscle cells.The abbreviation "CaM" refers to calmodulin, and "MLCK" refers to myosin light chain kinase, an enzyme that phosphorylates the light chains of myosin, stimulating smooth muscle contractions. How could this signal transduction pathway be shut off?

A key response in an egg to a signal from an entering sperm is

Refer to the figure showing the signal transduction pathway that is initiated by the binding of cortisol to its receptor. Based on the figure, which can you conclude about this signal transduction pathway?

"Crosstalk" refers to the

In transduction pathways used by cells, a physical or chemical stimulus from the environment acts as a

Choose the correct order for the following events in the interaction of a cell with a signal: (1) alteration of cell function, (2) signal binding to receptor, (3) signal release from source, (4) signal transduction.

Suppose scientists discover a new extracellular protein that causes increases in cell size.In order to investigate whether cell surface receptors are involved in binding this protein, they could

Signaling proteins that are characterized by their ability to bind GTP and GDP are known as _______ proteins.

Refer to the table below. Researchers investigated chemical signaling between two groups of cells located in the same region of a developing fish embryo.They isolated the two groups and tested the ability of group A cells to produce a cellular response to different conditions of incubation, as shown.The type of chemical signaling between groups A and B can be classified as _______ signaling, based on these results.

A chemical signal produced in the pituitary gland at the base of the brain binds to a receptor on liver cells.This signal would be classified as a(n)

Which is an experimental means that can be used to distinguish between a signal transduction pathway that uses a cell membrane receptor and one that uses an intracellular receptor?

Sketch the concept of signal amplification taking place in a signal transduction pathway.

Paracrine signals bind to

Why are signal transduction pathways highly regulated? What would happen if they were not?

Refer to the table below, summarizing key features of two signal transduction pathways that result in the same cellular response. Based on this information, which comparison is most reasonable?

Refer to the figure below. Which equation describes the rate of release of a ligand from a receptor? In all equations shown, "R" represents a receptor with no ligand bound, "L" represents a free ligand in solution, and "RL" represents a receptor bound to a ligand.

Which experimental technique would be useful in determining whether a particular chemical signal is a juxtacrine or a paracrine signal?