Chapter 3. The Cellular Level of Organization (sections 3.1 & 3.2)

D) Isotonic to its environment.

A cell that has neither a net gain of water nor net loss of water when it is immersed in a solution must be... A) Hypertonic to its environment. B) Hypotonic to its environment. C) Metabolically inactive. D) Isotonic to its environment.

Passive transport

Diffusion across a cell membrane does not require energy, so it is called ______.

D) Passive transport.

Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of A) Endocytosis. B) Active transport. C) Exocytosis. D) Passive transport.

Active

In ______ transport, a cell must expend energy to move a solute against its concentration gradient.

Isotonic

In a(n) ______ solution, the concentration of solute is the same on both sides of a membrane, and the cell volume will not change.

Hypertonic

In a(n) ______ solution, the solute concentration is higher outside the cell, water molecules move out of the cell, and the cell will shrink.

Hypotonic

In a(n) ______ solution, the solute concentration is lower outside the cell, water molecules move into the cell, and the cell will expand and may burst.

D) Would stay together but in a reverse orientation, with their tails projecting outward

In an oil-based, nonpolar environment, phospholipids would arrange themselves so that they __________. A) Would pack more tightly together than they would in a watery environment B) Would never associate but instead would remain as individual molecules completely dissolved in the oil C) Would not pack together at all D) Would stay together but in a reverse orientation, with their tails projecting outward

A) Microbes are engulfed into the macrophage via phagocytosis.

Macrophages are white blood cells that roam the body searching for invading microbes. Inside macrophage vacuoles these invaders are destroyed. How do the microbes get inside the macrophages? A) Microbes are engulfed into the macrophage via phagocytosis. B) The invaders cross the membranes via active transport through specific transport proteins. C) The invaders cross the membranes via facilitated transport through specific transport proteins. D) They are taken in by the form of exocytosis known as pinocytosis.

A) The diffusion of water.

Osmosis can be defined as... A) The diffusion of water. B) The diffusion of nonpolar molecules. C) The diffusion of a solute. D) Active transport.

B) The difference in water concentration across a selectively permeable membrane

Osmosis is often viewed incorrectly as a process driven directly by differences in solute concentration across a selectively permeable membrane. What really drives osmosis? A) The first law of thermodynamics B) The difference in water concentration across a selectively permeable membrane C) The difference in sugar or ion concentration across a selectively permeable membrane D) The difference in the height of water columns on either side of a selectively permeable membrane

A) The plasma membrane allows some substances to enter or leave a cell more easily than others.

Plasma membranes are selectively permeable. This means that... A) The plasma membrane allows some substances to enter or leave a cell more easily than others. B) Plasma membranes must be very thick. C) Anything can pass into or out of a cell as long as the membrane is intact and the cell is healthy. D) Glucose cannot enter the cell.

D) Easily pass through a membrane's lipid bilayer.

Small, nonpolar, hydrophobic molecules such as fatty acids... A) Very slowly diffuse through a membrane's lipid bilayer. B) Require transport proteins to pass through a membrane's lipid bilayer. C) Are actively transported across cell membranes. D) Easily pass through a membrane's lipid bilayer.

C) Helps to keep phospholipids from being too close to one another.

The cholesterol associated with animal cell membranes... A) Is an abnormality resulting from a diet high in cholesterol. B) Helps solidify the membranes when the room temperature is below freezing. C) Helps to keep phospholipids from being too close to one another. D) Is attached to membrane proteins and extends into the watery environment surrounding the cell.

Osmosis

The diffusion of water across a selectively permeable membrane is called ______.

D) Phagocytosis.

The process of a white blood cell engulfing a bacterium is... A) Osmosis. B) Pinocytosis. C) Receptor-mediated endocytosis. D) Phagocytosis.

A) Actively pump water back out of their cells to counter its inflow due to osmosis

Utah's Great Salt Lake has an average salinity seven times higher than that of the oceans. Very few multicellular organisms live in this harsh environment. An example is the brine shrimp, which must devote a large portion of its metabolic energy to osmoregulation. These brine shrimp must _____. A) Actively pump water back out of their cells to counter its inflow due to osmosis B) Actively pump water back into their cells to counter its loss due to osmosis C) Actively pump salt back out of their cells to counter its inflow due to osmosis D) Synthesize membranes that are impermeable to substances that upset osmotic balance

Fluid Mosaic Model

What does this image depict?

Pinocytosis

What is defined as cellular drinking?

Phagocytosis

What is defined as cellular eating?

Diffusion

What is the tendency of particles to spread out evenly in an available space?

B) Active transport moves solutes against their concentration gradient; facilitated diffusion moves substances down their concentration gradient.

Which of the following is an accurate comparison of active transport and facilitated diffusion? A) In both types of movement, phosphate groups alter the shape of transport proteins. B) Active transport moves solutes against their concentration gradient; facilitated diffusion moves substances down their concentration gradient. C) Facilitated diffusion requires the use of ATP; active transport does not require ATP. D) Active transport requires membrane proteins; facilitated diffusion does not require membrane proteins.

A) Active transport

Which of the following processes can move a solute against its concentration gradient? A) Active transport B) Facilitated diffusion C) Passive transport D) Osmosis

C) The concentration gradient is the driving force.

Which of the following statements is true for all types of passive transport? A) Only small polar molecules are able to cross the plasma membrane. B) Ions never cross the plasma membrane by passive transport. C) The concentration gradient is the driving force. D) Proteins are needed to transport molecules across the membrane.

A) Nine

You're on the pilot episode of a new reality show called "The Transport Factor." The host hands you three different amino acids, four different sugars, and two different ions. Then the host shouts, "How many different proteins does the cell need to move these molecules across the plasma membrane using facilitated transport?" Quickly, you correctly respond: _____. A) Nine B) Five C) Three D) One

Exocytosis

______ is used to export bulky molecules, such as proteins or polysaccharides.

Endocytosis

______ is used to take in large molecules.

A) Transport proteins; down

Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient. A) Transport proteins; down B) Energy and transport proteins; down C) Transport proteins; against D) Energy and transport proteins; against

B) The different membrane-enclosed spaces allow different parts of the cell to perform specific functions.

The eukaryotic cell has multiple membrane-enclosed compartments. This evolutionary innovation provides what advantage to the cell? A) The membrane-enclosed spaces allow for eukaryotic cells to be larger. B) The different membrane-enclosed spaces allow different parts of the cell to perform specific functions. C) The membrane-enclosed spaces have allowed eukaryotes to evolve forms of metabolism that no longer require the intake of any molecules from outside the cell. D) The membrane-enclosed spaces lead to the evolution of many different cell types when they are extruded to form daughter cells with novel functions

Phagocytosis, Pinocytosis and Receptor-mediated

The types of endocytosis are ______ , ______ and ______.

A) The direction of the oxygen concentration gradient

What controls the direction of a molecule, such as oxygen, involved in passive transport? A) The direction of the oxygen concentration gradient B) The size of the oxygen molecule C) The amount of energy available to transport oxygen D) The type of cell to or from which the oxygen molecule is moving

A) Exhibit a net movement to the side with lower free water concentration.

When two aqueous solutions that differ in solute concentration are placed on either side of a semipermeable membrane and osmosis is allowed to take place, the water will... A) Exhibit a net movement to the side with lower free water concentration. B) Exhibit a net movement to the side with higher free water concentration. C) Exhibit a net movement to the side with lower solute concentration. D) Exhibit an equal movement in both directions across the membrane.