Exam 6: Cell Membranes, Transport, and Communication

Which of the following could not easily diffuse across a plasma membrane?

Signaling molecules can affect a cell from the outside by interacting with specific receptors that are located

Water moves across a membrane from a hypotonic solution to a _____ solution.

Gap junctions allow large molecules to move from cell to cell.

A cell that is gaining water from its surroundings is in

Which of the following signaling molecules would not be found in animals?

The passive movement of water across a selectively permeable membrane is called ________.

The figure below illustrates a plasma membrane. Which molecule in the figure above is undergoing active transport?

Plants have hormones.

A concentration ______ is said to exist when a molecule is more abundant in one area than it is in another.

Two solutions are separated by a selectively permeable membrane that is not permeable to glucose. On one side of the membrane, solution A contains 10 percent glucose and on the other side, solution B contains 25 percent glucose. Which of the following is true?

Epithelial tissue in animals provides a barrier against the invasion of bacteria into the body. Which of the following is most likely responsible for creating a tight enough barrier to prevent the passage of bacteria?

To coordinate the contraction of the numerous muscle cells that form the heart, signals must travel rapidly between muscle cells. In order to allow this rapid communication, muscle cells in the heart must be connected by