LEARNSMART CHAPTER 4

A cell with a 0.5M concentration of salt inside it is placed into a solution. The cell begins to shrink. What is the possible concentration of salt outside the cell?

5.0 M

When a system reaches concentration equilibrium

Molecules continue to move but do not exhibit net movement in any direction

What would use a contractile vacuole to rid itself of excess water?

Parameclum

Proteins found on either the external or internal side of the membrane

Peripheral

The plasma membrane is described as a "fluid-mosaic." What does it consist of?

Phospholipids, cholesterol, and proteins

The form of endocytosis in which vesicle form around liquids or very small particles is called

Pinocytosis

Pinocytosis and receptor-mediated endocytosis serve much the same function. What is the difference between these two processes?

Pinocytosis is less selective

Which of the following are considered membrane-assisted transport?

Pinocytosis, phagocytosis, and exocytosis

Which structure controls the movement of substances into and out of the cell?

Plasma membrane

When a plant is placed in a hypertonic solution, its cells lose water and its cytoplasm shrinks; this form of osmosis in plant cells is called

Plasmolysis

The soidum-potassium pump moves sodium ions to the outside of the cell and potassium ions to the inside of the cell. Both ions are moved against their concentration gradient. This type of transport is called

Active transport

What junction is a cellular junction that has intracellular filaments mechanically connecting the cytoplasmic membrane of adjacent cells

Adhesion junction

Which type of membrane protein may have a hormone like insulin bind to it?

Receptor protein

Which form of bulk transport is highly selective?

Receptor-mediated endocytosis

Secretion that occurs only in response to a specific signal is called

Regulated secretion

Which types of molecules are more likely to be able to diffuse across a plasma membrane?

Small, uncharged, and nonpolar

A solution contains both a _______ and a ________

Solute and Solvent

Factors that will influence the rate of diffusion

Temperature, electrical currents, pressure, and molecular size (NOT LIGHT)

Which of the following are needed to complete active transport of molecules?

Carrier protein, plasma membrane, and energy

What is true about all carrier proteins?

Carrier proteins aid in both facilitated transport and active transport; carrier proteins are specific to a single type of molecule

What is the role of enzymatic plasma proteins?

Catalyzing metabolic reactions near plasma membrane

Which of the following is an example of active transport?

Cell pumps H+ ions into the mitochondrial intermembrane space, which allows H+ into the matrix.

A newly transplanted organ is rejected by the immune system of the host. Which protein is responsible for the rejection?

Cell recognition protein

The major component of the plant cell wall is

Cellulose

Both carrier and _____ proteins are involved in passive transport of molecules through the cell membrane

Channel

The lipid molecule that stiffens and strengthens the plasma membrane and helps regulate its fluidity is known as

Cholesterol

General term for transporting materials into a cell by the formation of a vesicle

Endocytosis

A vesicle fuses with the plasma membrane as secretion occurs and macromolecules move out of the cell during

Exocytosis

Two transport mechanisms that lead to the formation of a vesicle inside the cell

Exocytosis and Endocytosis

The protective meshwork of proteins and polysaccharides located externally to the cell is called

Extracellular Matrix

Which are a passive process?

Facilitated transport and diffusion

Diffusion is defined as the movement of molecules from ____ concentration to ___ concentration

HIGH ; LOW

Marine animals compensate for the hypertonic environment by

Increasing/decreasing the amount of urea in its blood until it is isotonic with its environment, excreting salt across their gills, and by secreting salt in tears from a gland near their eye

What serves to separate the internal environment of a cell from its external envrionment, allowing the cell to maintain homeostasis

The plasma membrane

Which type of protein would more likely be able to function as a channel through the plasma membrane?

Integral protein

Which part of the plasma membrane is nonpolar?

Interior, where the fatty acid tails are located

A solution that is equal in solute concentration to that of the cytoplasm of a cell and causes a cell to neither lose nor gain water by osmosis

Isotonic

Why does the sodium potassium pump require energy?

K+ and Na+ are moved against their concentration gradients

Which type of membrane transport leads to the formation of vesicles?

Membrane assisted transport

Which direction do the phosphate heads of the phospholipids in the plasma membrane face?

Towards (?)

Which of the following best explains why a hypotonic solution causes a cell to swell

Water rushes into the cell

What best explains why a hypertonic solution causes a cell to shrink?

Water rushes out of the cell

After inhalation, oxygen gas is more concentrated in the ____ and diffuses into the ____

alveoli ; blood

Channel proteins located in the plasma membrane for the passage of water are called

aquaporins

Cell receptor proteins are involved in

binding signaling molecules to bring out physiological changes

The gradual increase or decrease in concentration from one point to another constitutes a

concentration gradient

The shrinking or shriveling of animal cells placed in a hypertonic solution is called

crenation

If salt diffuses from an area of high concentration to an area of low concentration, the salt is moving

down its concentration gradient

The MHC cell recognition molecules are

glycoproteins

The cytolysis of red blood cells is specifically called

hemolysis

Turgor pressure is increased in a plant cell when it is placed in a

hypotonic solution

A solution that has a lower solute concentration to that of a cytoplasm of a cell is

hyptotonic

Osmosis is defined as the

movement of water across a selectively permeable membrane

The general term for the pressure that may build in a cell as a result of osmosis is called

osmotic pressure

The plasma membrane is described as being selectively

permeable

Engulfment of a bacterium by a white blood cell occurs via

phagocytosis

The channels located in the cell wall of plants which enable adjacent cells to readily exchange materials are called

plasmodesmata

In the cell signaling pathway, the series of relay proteins that ends in the activation of a targeted protein is called the

transduction pathway