BIOS 251 - EXAM 2 REVIEW COMPLETE
SOLUTION RATED A+
What is the purpose of the Cytoskeleton? It provides structural support for the cell, aides
in cell motility (Movement) and moves organelles.
What are cells composed of? They are composed of a plasma (Cell Membrane), cytoplasm,
cytosol, nucleus, and cytoskeleton.
CytosolClear gel within the cell sometimes referred to as Intracellular Fluid (ICF).
Cytoplasm ALL FLUID and COMPONENTS between the nucleus and cell membrane
(Includes the cytosol and cytoskeleton).
What molecules are embedded in the phospholipid bilayer? Transmembrane proteins,
peripheral proteins, cholesterol, and sugars (glycolipids and glycoproteins).
Plasma membrane proteins? Membrane channel proteins, Glycoproteins, Enzymes, CAMs,
Receptor proteins, and Second-messenger system.
What is the function of a receptor? Binds to chemical messengers such as hormones sent
by other cells.
What is the function of an enzyme? Breaks down a chemical messenger and terminates its
effects.
What is the function of a channel? Allows solutes to pass into and out of the cell. Always
open.
What is the function of a gated channel? Opens and closes to allow solutes only at a
certain time
What is the function of a Cell identity marker (Glycoprotein)? Distinguishes the body's
own cells from foreign cells.
What is the function of a Cell Adhesion Molecule (CAMs)? Binds one cell to another
What is passive transport? The movement of materials across the cell membrane without
using energy (ATP). Occurs from high to low concentration.
What is simple diffusion? Molecules move from high to low concentration, with or
without a membrane, and with or without channel proteins.
, What is facilitated diffusion? Polar molecules move through a channel protein, from a high
to low concentration.
What is osmosis? WATER MOLECULES move directly through a membrane or through
special proteins called Aquaporins. High to low concentration.
What is hypertonicity? Solutions have high ECF osmolarity. Water moves out of the
cell, causing the cell to shrink.
What is Isotonicity? Solutions have the same osmolarity, no movement into or out of the
cell.
What is Hypotonicity? Solutions have low ECF osmolarity. Water moves into the cell, causing
swelling and potential bursting.
What is active transport? Utilizes energy to move substance against the concentration
gradient, lower to higher concentration.
Depends on a few factors: ATP, membrane proteins, concentration of molecules, and
membrane potentials.
What is bulk transport? The movement of large molecules by way of vesicles.
What is endocytosis? Transports materials into the cell
What is phagocytosis & pinocytosis? phagocytosis brings in solids (cell eating) and
pinocytosis brings in liquids (cell drinking).
What is exocytosis? The transportation of materials out of the cell.
What is intracellular and extracellular fluid? Intra - Known as cytosol, more gel like than ECF
Extra - Sometimes called "tissue fluid", includes plasma.
What is voltage? Any difference in electrical charge (+) or (-).
The uneven distribution of ions across the membrane is controlled by protein pumps and
leak channels. Resulting in more (+) ions outside, and more (-) ions inside the cell.
What is the resting membrane potential value? RMP = -70mV
sodium-potassium pump Moves 3 sodium ions out & 2 potassium ions into the cell.
Creates a (-) charge in the cell.
Muscle and nervous system rely on it.
Explain Depolarization and Repolarization Depolar - Na+ channels open and Na+ enters
cell making it more positive.
SOLUTION RATED A+
What is the purpose of the Cytoskeleton? It provides structural support for the cell, aides
in cell motility (Movement) and moves organelles.
What are cells composed of? They are composed of a plasma (Cell Membrane), cytoplasm,
cytosol, nucleus, and cytoskeleton.
CytosolClear gel within the cell sometimes referred to as Intracellular Fluid (ICF).
Cytoplasm ALL FLUID and COMPONENTS between the nucleus and cell membrane
(Includes the cytosol and cytoskeleton).
What molecules are embedded in the phospholipid bilayer? Transmembrane proteins,
peripheral proteins, cholesterol, and sugars (glycolipids and glycoproteins).
Plasma membrane proteins? Membrane channel proteins, Glycoproteins, Enzymes, CAMs,
Receptor proteins, and Second-messenger system.
What is the function of a receptor? Binds to chemical messengers such as hormones sent
by other cells.
What is the function of an enzyme? Breaks down a chemical messenger and terminates its
effects.
What is the function of a channel? Allows solutes to pass into and out of the cell. Always
open.
What is the function of a gated channel? Opens and closes to allow solutes only at a
certain time
What is the function of a Cell identity marker (Glycoprotein)? Distinguishes the body's
own cells from foreign cells.
What is the function of a Cell Adhesion Molecule (CAMs)? Binds one cell to another
What is passive transport? The movement of materials across the cell membrane without
using energy (ATP). Occurs from high to low concentration.
What is simple diffusion? Molecules move from high to low concentration, with or
without a membrane, and with or without channel proteins.
, What is facilitated diffusion? Polar molecules move through a channel protein, from a high
to low concentration.
What is osmosis? WATER MOLECULES move directly through a membrane or through
special proteins called Aquaporins. High to low concentration.
What is hypertonicity? Solutions have high ECF osmolarity. Water moves out of the
cell, causing the cell to shrink.
What is Isotonicity? Solutions have the same osmolarity, no movement into or out of the
cell.
What is Hypotonicity? Solutions have low ECF osmolarity. Water moves into the cell, causing
swelling and potential bursting.
What is active transport? Utilizes energy to move substance against the concentration
gradient, lower to higher concentration.
Depends on a few factors: ATP, membrane proteins, concentration of molecules, and
membrane potentials.
What is bulk transport? The movement of large molecules by way of vesicles.
What is endocytosis? Transports materials into the cell
What is phagocytosis & pinocytosis? phagocytosis brings in solids (cell eating) and
pinocytosis brings in liquids (cell drinking).
What is exocytosis? The transportation of materials out of the cell.
What is intracellular and extracellular fluid? Intra - Known as cytosol, more gel like than ECF
Extra - Sometimes called "tissue fluid", includes plasma.
What is voltage? Any difference in electrical charge (+) or (-).
The uneven distribution of ions across the membrane is controlled by protein pumps and
leak channels. Resulting in more (+) ions outside, and more (-) ions inside the cell.
What is the resting membrane potential value? RMP = -70mV
sodium-potassium pump Moves 3 sodium ions out & 2 potassium ions into the cell.
Creates a (-) charge in the cell.
Muscle and nervous system rely on it.
Explain Depolarization and Repolarization Depolar - Na+ channels open and Na+ enters
cell making it more positive.
